#6

[speedpro]

I have the engine dummied up and have been checking deck height etc. I have a few pistons which when fitted to the cylinders have less than .002" clearance. .002" is at the top end of the range for clearance so a little bit of room to possibly re-finish the surface of the cylinders, possibly. The piston squish to gasket surface is about .015". The top of the cylinder block and the sleeves is a bit uneven so taking that .015 off will be good to even it out. That will leave the head gasket thickness for clearance which is .25mm. There is no mention of the clearance in the spec sheet.
I've also been smoothing out the combustion chamber particularly around the valves. The dremel plus a 3mm ball cutter seems OK. I've been over some of it with a little sanding drum as well.

Got me thinking back to a job I did on a couple of Chevy alloy BB heads one summer. Used the big grinder there and a balls out 7 flute cutter primarily. Still took the better part of a week to do. Steel bodied Holden ute did 200+mph at Meremere so reasonably happy with the outcome.

[speedpro]

Slowly getting things together. Hope to get the machining done on the heads to fit the cam locating discs into this weekend. Also measured the current installed height of the springs. Every single one I have measured is about .5mm over length on the piece of head I have decided to use. These are the valves that were installed originally in each port and which I don't think have been touched. I need to double check but every valve I measured, the installed valve spring height is over the spec sheet value. I'll check the old head as well. That head had a bit of work done when I originally built the engine.
I want to check the height to the end of the valve stem. Obviously, cutting valve seats and valves will reduce the clearance. Once I can get the cams in I will assemble one exhaust and one intake valve and shim in up. This will tell me how far the valve tip can be raised before I reach the limit of the shims. The good thing is that the valve stems are a reasonable distance proud of the spring retainer base of the shim pocket so I can grind the end of the valve stems if needed. I had to grind the end of the valve stems on my old Moriwaki Z1 and had the ends tipped with wear braze so it isn't anything new.
On the cylinder I have decided to take the bare minimum off the deck. I'm not totally sure about rod stretch but at 18,000rpm it has to be considered.

[speedpro]

Bit of annoyance with what I found this afternoon. I pulled the springs off the good inlet valves on the blown up head. There wasn't any valve spring seats under the springs. I measured a few things and determined that the installed height of the valve springs was about 1.5mm too long. The spring seats out of the 3LN head are 1.1mm so if they had been installed that would have put the installed height at about the same as the 3LN springs. Still too long but a lot better. This would have been the major factor in the engine not wanting to rev much over 14,000rpm and the air/fuel going lean - valve float. Pretty annoying considering what it cost to have that head reconditioned when I first built the engine.
I was also reminded that the 2KR & 3LN springs are different. The 2KR springs have a slightly thicker wire and are about .5mm shorter. The 2KR springs are also less progressively wound at the base.
The new head is going to be assembled to specification with maybe .5mm less installed height on the valve springs just to be sure.

I posted earlier about working the combustion chamber. It has been suggested that I should smooth the sharp edges where the chamber meets the gasket surface. I'm hesitating as I really don't know about doing that. In 2-strokes the sharp edge where the squish meets the bowl is critical to making power and i wonder if the same concept applies to the 4-stroke.

What I did on my Z1 turbo was completely remove anything on the head around the combustion chamber that would have made a squish area with the flat top turbo pistons. It was one big combustion chamber, no squish at all. That engine does make enough horsepower but early on there was issues with ring lands cracking and I wonder if the detonation that probably caused it was made worse by the lack of squish area. It was sorted in the end with a methanol/petrol/toluene mix.

[Grumph]

Squish bands - I'd just break any sharp edge left after head machining. Hand scraper will do it.
Sharp edges could be trouble under high heat and load.
I set mine to just under .040in squish clearance - but I have heavier pistons than you.

Springs - the amount you can pack them is dependent on how far away from coil bind they are at full lift.
From memory, .020in was safe on mine.

The small amounts you've cleaned out of the chambers will have an effect on the compression ratio.
Have you measured it yet ? What are you aiming for ? This very small chamber size is probably safer at high boosts than a big area 2V so higher CR should be possible.
When I did the blown EX500, we had a pipeline into the Penske engine shop - a kiwi was doing his development.
The Cosworth turbos were the same bore size and used 9:1 com on Methanol. Good enough for us to copy.

[speedpro]

I've gone ahead and taken all the sharp edges off using the dremel and a little sanding drum. I'll probably finish it off with a bit of Wet&Dry.
Got the valve thing sorted.
1st do seats and valves
2nd check height of valve end from spring bottom, adjust so shims will be in range
3rd check spring installed height and install shims under spring base as required
4th assemble and shim for valve clearance

[Grumph]

I'll be surprised if you have to tip the valves. mine were around 1.9 - 2.15 from memory.

The two box Hot Cams set of 7.48mm shims I have runs from 1.2 to 3.5mm.

Bought off Spannerspinner on here when he offered them cheap....

[speedpro]

NZ Cylinders have the head. Things are marginal as far as tooling goes for the tiny valves but it sounds like it may be possible. Unfortunately it isn't worth their while to purchase tooling due to me being the only idiot in NZ willing to pay for a proper valve job to be done on a FZR250 cylinder head. It's a shame really because there are definite improvements to be made even on a good head. Old worn heads will show a significant improvement if good work is done and they are setup properly.

[Grumph]

NZ Cylinders have the head. Things are marginal as far as tooling goes for the tiny valves but it sounds like it may be possible. Unfortunately it isn't worth their while to purchase tooling due to me being the only idiot in NZ willing to pay for a proper valve job to be done on a FZR250 cylinder head. It's a shame really because there are definite improvements to be made even on a good head. Old worn heads will show a significant improvement if good work is done and they are setup properly.

I believe there is an optiional very small tool holder for the Serdi head machines. It's rare but there is one in ChCh. But it's in Barry Lynch's collection of machinery - which afaik is now sitting idle.

I'd be surprised if no-one else had one. There are certainly enough Serdi's around now.

[speedpro]

Bit of an update on the other twin, my son's Honda CB125T. The engine went "off" at the end of the 2-hour at Tokoroa. A new 150cc cylinder kit was ordered from China and was on the doorstep about 10 days later. The 125cc engine in it was showing lots of blowby so it seemed logical. Once I started measuring everything I found a big end bearing was trashed. Luckily when discussing it with Becks she pointed out the ESE had a CB125T engine which was duly purchased for a very reasonable price. At one point in time there were 3 CB125T engines in pieces in my garage as I chose the best part options for the new engine. The new engine has the cases, crankshaft, and gearbox from one engine. My modified clutch from the Tokoroa engine, the new block, and the head from the original JCR 150cc engine from the original bucket along with the JCR camshaft. I skimmed 1mm off the block and used the JCR head which was also skimmed. This caused a problem with the camchain tensioner running out of travel meaning I had to dismantle the topend to fit the modified tensioner from the JCR engine. Now the intake valve were kissing the piston but only on one cylinder. I backed the cam timing off just enough to leave .6mm valve to piston clearance on overlap. I also replaced the old square-section seals on the intakes with viton o-rings. Strangely the motor isn't so hard to start now and doesn't seem so cold-blooded. It doesn't sound like all that much work but there is a good solid week of work gone into it.

[speedpro]

One thing I didn't mention is that the CB125T is a bit harder to turn over now. I managed to bump start it in 2nd down my drive but had to be in 3rd to get it to turn on the dyno today. Rob gave me a hand to give it a few revs to try it out on the dyno before dragging it to a race track only to find it doesn't work. Unfortunately the software/hardware wasn't playing nice so we don't have a number. After a good warmup it seemed to be running well. The revs were built up over a few runs through the gears and the engine was sounding real sweet, very crisp and responsive. Rob and I both suspect it's making more power than before based on how quickly it revs through the gears. We've had it on the dyno a few times so have a good idea how it typically runs on the dyno. Only one slight concern is a puff of smoke at each downshift. The 150 kit came with new valve guide seals which have been fitted but I did have a concern about the spring retainer hitting the seals with the JCR cam. I'm going to try better oil to see if it helps. Maybe it just needs a bit more bedding in as well.

[speedpro]

The FZR has been getting love as well. I fitted the cams to the new head but really wasn't happy with how far off-centre the lobes were on the tappets. In the end I have remachined the previously unused recesses in the end of the head where the cam locating discs now run. Even with the recesses widened the cams couldn't be moved over far enough to centralize the lobes. I have machined one cam and have ground the majority of the disc off the other and will hopefully machine the 2nd one tomorrow. The disc on the end of each cam is reasonably hard. Combined with the hole in the disc it made for an interrupted cut of a hard material and the carbide tips weren't lasting long. Once both cams are finished I'll make a new disc for each cam that will be pressed and welded onto the cam which will fit into the new recess and locate the cam correctly.

[pete376403]

As this seems to be the most popular bucket thread - are you allowed to use a rotary (Wankel) engine in buckets? I saw today in a second hand shop a lawnmower with a Sachs rotary. No idea what size, whether is goes or anything els but was tempted by the $100 price.

[husaberg]

As this seems to be the most popular bucket thread - are you allowed to use a rotary (Wankel) engine in buckets? I saw today in a second hand shop a lawnmower with a Sachs rotary. No idea what size, whether is goes or anything els but was tempted by the $100 price.

buy it but it s too big to be legal but buy it anyway.

[F5 Dave]

. . . And there are no provisions for rosaries, dam autocorrect

[diesel pig]

As this seems to be the most popular bucket thread - are you allowed to use a rotary (Wankel) engine in buckets? I saw today in a second hand shop a lawnmower with a Sachs rotary. No idea what size, whether is goes or anything els but was tempted by the $100 price.

chapter 10 of the MNZ rule book applies to all road racing machines

10.11 The Formulae to Calculate Cubic Capacity:

Rotary combustion (Wankel Patent): Capacity of one working chamber
in cubic centimetres, multiplied by number of rotors, multiplied by two

Wankels operate on the foul (four) stroke principle so for F4 class Buckets a capacity of 158cc applies.

I suggest teaming it up with a CV transmission like TZ350 has been playing around with.

[husaberg]

chapter 10 of the MNZ rule book applies to all road racing machines

10.11 The Formulae to Calculate Cubic Capacity:

Rotary combustion (Wankel Patent): Capacity of one working chamber
in cubic centimetres, multiplied by number of rotors, multiplied by two

Wankels operate on the foul (four) stroke principle so for F4 class Buckets a capacity of 158cc applies. then times 2

I suggest teaming it up with a CV transmission like TZ350 has been playing around with.

Hi its 150cc/2 for a Wankel so it has to be 75cc odd
the Car guys rules used to be 1.7x rather than 2x they nearly fits in on those. from memory they were arround 110cc or 150cc
a guy in NZ put one in a MB100 honda its on youtube somewhere.


https://youtu.be/dOsCUtEE_W8
https://www.youtube.com/watch?v=l7UtKa-xiFw

[F5 Dave]

I think the handlebars tell you all you need to know. Waste of an MB100 bottom end.

[speedpro]

I turn my back for a month and look what happens . . . . . .

Anyway, I'm back. I've been slowly getting little bits done here and there and managed to machine the washers for the end of the cams today. The internal holes had to be slightly different sizes but it all worked perfectly as both washers need to be slightly heated to slip on the cam. Now that I have sanded and ground them smooth they are a nice fit in each slot. I do need to take maybe .1mm off each face where it presses up against the cam to get the cam centred just right. I'll clock them up in the 3-jaw tomorrow hopefully and whiz a bit off. Hopefully welding won't cause any problems with movement and I won't have to do any further machining. I'm pretty happy with how this is coming out.

348481348482348483348484

[speedpro]

Slowly getting things done. I have now cut the end off the inlet cam and welded in a bung. I'm getting the hang of getting the sizes exactly what I want. The bung is the same size as the hole in the cam on the inside end and .01mm larger on the outer end. A gentle tap was needed to get it in. Both washers are now welded to the ends of the cams. I ran a small stone over the ends to make sure there were no bumps that were going to bind in the aluminium. It's come out reasonably good. I have decided to make a new steel boss to mount the 1-tooth cam trigger onto. The old one is alloy and not ideal. I'll make the new one out of steel and weld it in. I'll need to spin it in the lathe to make dead certain it runs true. The cam end boss was one lobe that I ground down using my high speed grinder in the tool post on my old lathe. I'm pretty sure that Kevin isn't going to be too happy about me grinding anything in his lathe.

[speedpro]

The exhaust cam is nearly finished. The new boss is welded on and machined to size. I just need to finish the thread to hold the trigger on

[speedpro]

I'm looking at doing the cam timing and need a boss to mount the degree wheel. Ideally I'd like the boss from the middle of the alternator flywheel. I can machine something to do the job but would prefer something with the slot for the woodruff key but don't want to mess around cutting the slot, besides not knowing how to.
If anybody has a rotor from a late 3LN that they don't want please PM me. Thanks

[speedpro]

I have been thinking about how best to determine TDC for doing the cam timing. For fuel and ignition purposes which are fine tuned on the dyno it doesn't matter much. For exact cam timing and repeatability it is critical. The methods I have been using to date have a small error due to the offset gudgeon pins, and in other engines due to offset bores. Any other engineering that means a reciprocating part connects to the rotating assembly by anything not exactly in line with the bore centreline and crank centreline, which must be the same centreline, introduces a difference in degrees of crank rotation for the same piston movement either side of TDC. If a piston stop is used and the crank rotated in each direction until the piston hits the stop, the crank will be in a slightly different rotation position each side, meaning TDC is not exactly in the centre point between the 2 positions where movement is blocked by the stop.
I came up with the following solution. There is no doubt that the piston is at TDC as there is a screw in the crown pulling it up. The piston can go no further so it is at TDC. As usual with the FZR engine everything is right on the money. I just need a boss to mount my degree wheel and I'll be away.

[speedpro]

One more little step now that I'm back in Auckland. Made a little alloy boss to go on the end of the crankshaft for the degree wheel. One thing I learned talking with Jim is how tapers are dimensioned. It turns out the taper in the rotor is 4mm larger diameter for a 10mm movement along the axis, to within .01mm anyway so it probably is. Some tapers are at various angles but others are a specific diameter increase per axial movement.

[F5 Dave]

Sorry to hear that. Didn't know that you had made it out. Back by accident I guess.

[Grumph]

TDC is TDC regardless of any piston offset. You'll be moving the cams anyway if it doesn't work at whatever figures you start off with.

What lobe centers do you propose to start with ?

[speedpro]

TDC is slightly different dependent on pin offset as the pin is pulling the rod very slightly to the front or back which will result in the crank being rotated very slightly to the front or back. Simple trigonometry will give you actual numbers. I'll zero it up with the piston installed correctly and then again with the piston backwards. It might be a while as I'm busy working on the scooter at the moment to get it all legal.

[speedpro]

The only change between the 2 attached photos is that the piston was turned around.

[husaberg]

The only change between the 2 attached photos is that the piston was turned around.

Okay but its only an abitrary reference to set to and then alter to what the engine likes.
besides i would pick the pins prevent them from turning around during running.:msn-wink:

[Grumph]

Okay but its only an abitrary reference to set to and then alter to what the engine likes.
besides i would pick the pins prevent them from turning around during running.:msn-wink:

The head doesn't care where the crank is when the piston is closest to it. Airflow timing is based around piston movement which can just as easily be measured in distance down the bore. Crank angular measurement is used for convenience.

i wouldn't count on the pins restricting angular movement. I well remember looking at a hot RGV250 that Grant Ramage had pulled the bottom head off - and seeing the arrow marking the front pointing to the side....And no, it wasn't his proddy one.

[speedpro]

Surprising amount of work to get this engine back together with lots of adjustments being made to get most things fitted back together properly. The engine should be back in the bike and reconnected next week. Then it should just be a matter of recalibrating the triggers and I should be able to fire it up. The triggers need recalibrating as the cam trigger will be remounted on the new boss and won't be where it was previously. Initially I'll leave the turbo off and just run the throttle body with velocity stacks and a simple 2:1 exhaust. I have short 3D printed velocity stacks but will print longer ones to try as well. There'll be no science involved in their design. One thing I would really like to try in the future is a properly designed pair if megaphone pipes. If anybody can help with megaphone design I would be interested in a chat.

[husaberg]

http://www.victorylibrary.com/brit/mega-c.htm

personally i would copy a 1960s honda RC 250/4 for the megga desgn but the problem is they make carburation very hard at 3/4 speed

if it help this is WHat honda made for the MC22 based race bike they made
yeah it looks like a MC19 to me too.
349261

[Grumph]

To a large extent those full length Honda pipes were dictated by FIM regs. The exhaust system must not go past the end of the bike and i think at that point they had to finish past the footrests too.
Current theory is fully tapered headers which are much shorter.
Then you hit what i thought long about - it's a 180 deg twin. I've done a lot in the past with this layout using 2:1 and separate pipes. Spread favours 2:1, max power individual pipes.
I've made individual pipes for mine - stepped. Start out at 1 1/8in OD and step up in 3 stages till they match the ID of the short mufflers at 1 1/2in.
The trick is to work out the tuned length, take your starting ID and draw a 2 degree taper over that length. Where the ID drawn matches available pipe sizes, put a step. It flows just the same as a full taper.

[husaberg]

140 pounds of Boost (diesel)2,200 horsepower he has made 3000hp previously out of 6.7l

https://i.4pcdn.org/o/1591561710702.gif
https://jalopnik.com/watch-this-diesel-engine-explode-with-more-boost-than-g-1820919660
https://www.dieselworldmag.com/diesel-technology/the-outer-limits-inside-diesels-most-extreme-competition-engines/

[speedpro]

I follow Power Driven Diesel on You Tube. They are regularly getting 2000+hp and the bosses truck they were looking at 3000hp at the last competition before it spat the block out of the truck. They've logged 200lbs boost on drag runs. I knew the Top Fuel guys and others in that area were running tool steel camshafts but so do the diesel guys.

[speedpro]

The bike is back together and as far as I can tell it's ready to run. The printed velocity stacks look the part. I'm leaving the turbo off. Over the last couple of days I've been going back over the ECU software. It should just be a matter of calibrating the triggers and firing it up. Looking at "Quick Tune" today and it shouldn't be too hard to get it sorted initially.

[F5 Dave]

The Duzall really needs a cap on it especially if you store it up high.

[Grumph]

The Duzall really needs a cap on it especially if you store it up high.

The little rubber caps that come on battery breathers make excellent caps for that.

[F5 Dave]

I've managed to keep mine but the bugger does try to escape on a semi regular basis.

[husaberg]

The bike is back together and as far as I can tell it's ready to run. The printed velocity stacks look the part. I'm leaving the turbo off. Over the last couple of days I've been going back over the ECU software. It should just be a matter of calibrating the triggers and firing it up. Looking at "Quick Tune" today and it shouldn't be too hard to get it sorted initially.

Everytime i see this engine especially now with the bellmouths i think of this one
https://live.staticflickr.com/5328/31217720772_5bebf594b3_b.jpg

[Grumph]

Everytime i see this engine especially now with the bellmouths i think of this one

Well, scale your imagination down to about half size. The cut engines are tiny.

[husaberg]

Well, scale your imagination down to about half size. The cut engines are tiny.

I am pretty sure i saw yours before and after it was cut....

150 vs 750
I would same although the casings were huge and heavy 40lb the cozzy was smaller than it looks, about the size of a CB350 but was 200Lb and had 75lb of spinning mass.

What happen re your carbs

[speedpro]

Today with help from Rob at ESE I managed to get the engine running. I checked the trigger calibration and found it was still perfect(ish) despite the new cam trigger at some unknown new position. Obviously I don't understand how that works. Put the fuel pump fuse in, turned on injection, 3rd gear, pressed the button and away it went. Everything was looking good apart from the fuel which wasn't totally unexpected. I will need to go over the fuel pressure regulator as it didn't adjust at ESE but was fine when I got home. We didn't do any hard runs, just ran it through the gears using middling revs, and it was reasonably sweet. with the velocity stacks the intake is very noisy now. We ended the day with a little problem. When I was using a bit of throttle Rob was seeing water being blown out of the overflow bottle. The amount of water was dependent on throttle so I'll check compression but will probably have to remove the head and try to seal it better. All up I'm pretty happy with how it went.

[speedpro]

Borrowed this tool from friend Kevin to pressurise each cylinder. Waaaaaay flasher than needed but worked a treat. Cylinder #1(was #3) blows bubbles out of the radiator when pressurised. It won't be hard to fix and there are a few options.

[speedpro]

Well, that got tricky real quick. The motor has been taken apart down to the crankcases. Everything looks OK apart from the head gasket issue. I took the cylinders over to Kevin's workshop and we measured it on the granite table. The cylinder has a slight twist, about .003" and will rock if diagonally opposite corners are pressed. The sleeves are also about .001" below the surface of the alloy block. With the thickness of the gasket sealant around the outside that leaves plenty of clearance for a failure of the seal around each bore. The plan for tomorrow is to mount the cylinder on 3 points with the base up, with only sufficient force to hold it down but not to distort it. Then take just enough off the base of the alloy block to make it flat. Once it's flat the block can be flipped over and clamped down on parallels and using a small cutter mow a bit off the top to make it flat. Once it's flat I'll probably take about .001" off the alloy block leaving the sleeves proud. I'm not going to check how square the bores are to the top and bottom surfaces. I'd check the head as well but am going to risk it rather than open another can of worms. Kev has a brand new 6mm cutter I'm allowed to use. It should come out real nice.

[F5 Dave]

Bit of Selleys All Clear will fix it.

[Grumph]

The cut barrels have no torsional stiffness whatsoever. Mine got decked once the new liners were in. Clamped down using the base gasket area as a datum and decked parallel to that. Liners are flush, copper head gasket - painted - and so far it's holding.
Over the years, working on FZR's of all sizes, i've noted the importance of lubing the head nuts when torquing them down. Generally, they're marginal for size in the application and any reduction in tightening torque shows as a gasket leak. 400's are particularly prone to this.

[speedpro]

I did think of bolting the cylinder down on the base gasket surface and decking it. Doing this worked on the Z1 without a problem. All the fasteners are lubed prior to assembly. If you have the torque setting for the head studs that would be useful. I took them down to 25nM last time but it seemed a bit light. 25 is the recommended torque for 8mm fasteners according to the spec sheet with the torque wrench.

[Grumph]

i went from memory. the 8mm head studs on the 400's are spec'd at 18 ft/lb. They'll take 20 ft/lb no probs - so that's what I did the cut 250 to.

[speedpro]

I only decked the top of the cylinder. I looked back at my own experience with a slightly twisted Z1 block and how that was clamped to a 40mm thick slab of steel to keep it flat while machining. Well that was the idea but the engine reconditioners knew better and took it off before boring with the result that the bores weren't square to the crank once it was all bolted back together. Greg also commented about his experience with these cylinders. I clamped it down as per the photo. I took a very small initial cut of maybe only .002" and that resulted in a very even cut over the whole surface with possibly a smidge lighter cut on the top of the sleeves. After that I made another cut of just the aluminium. I raised the knee less than 1 graduation(.001") which resulted in the sleeves being proud by .02mm. It should work perfectly.
349384

[speedpro]

Bike is back together and fired up 2nd push down the drive. Ran it for a while warming it up and it stuttered to a stop. I toggled the power but the pump didn't build fuel pressure which I thought was odd. I topped up the fuel and tried again and it was OK. Another push down the drive and it was away. After another period it stuttered to a stop again. I suspect the fuel pump but need to look into it a bit further.
Once it was warmed up I did give it a couple of good blips. It pulls 14,000 quickly and the log file shows clean curves. Hopefully once the fuel issue is fixed and it's tuned it will rev freely and make some power.

[speedpro]

The Honda CB125T has a new home. Bit of a shame we didn't manage to run it on a track with the new 150cc kit. Hopefully it will be at the next Tokoroa round.

[speedpro]

Back working on the Yamaha FZR twin. I had a suspicion about the fuel pump. I had to turn the adjustable fuel pressure regulator until flow was stopped to get only 2.8bar pressure. I tried an original regulator but it was a faulty one and fuel pressure was only going to 1bar. Eventually swapped out the fuel pump for one on loan from Rob and straight away had more flow at the lower pressure by the looks of the bubbles scooting round in the clear portions of the fuel lines. With the rising rate regulator I was able to easily increase fuel pressure over 3bar whilst maintaining plenty of flow. With the manifold input open to ambient I've set the pressure to 3bar. With the engine running the fuel pressure should drop down but when it pulls boost the pressure should increase which is what I want. This has been another good exercise to remind me about measuring everything.

[speedpro]

I'm still not happy about the fuel pressure. I was doing work on the bike today and ran the pump. The pressure was going over 3bar despite when I last ran it having it set to 3bar. I adjusted it easy enough but it casts suspicions on pressure regulation so I'll be keeping an eye on it. I might even log fuel pressure using a spare analogue input. The main thing I was looking at today was the cause of oil seeping out around the cam cover. I suspect the problem is an oversupply to the head. I did have the banjo bolt in the head with the roughly 1mm restrictor hole. I didn't have a problem with the other engine with or without the turbo. What I suspect is that due to only having half the head all the oil is being supplied to the remaining side and it is simply too much. Greg had a similar problem and hopefully has gotten around it by adding a drain. As an experiment I added a 2nd restricted banjo bolt to the crankcase end of the feed pipe. I'll try it tomorrow probably. The turbo supply line has a 1mm restrictor in it to reduce the flow to the turbo. The main man in Greenlane Speed Shop informed me it would be required back when I bought the supply line for the turbo. I have a gauge on the main oil supply gallery and the pressure is sitting around 60psi. I find it surprising how the supply needs to be restricted. There is a small restrictor in the crankcases as well but I think that is to stop all the oil falling through the gearbox bearings leaving non for anywhere else. My turbo Z1 has a 7mm restrictor on the oil pump outlet in an attempt to gain a bit of pressure to the turbo. In that case I'm pretty sure it still only goes to about 5psi. that pressure feeds the galleries that go to the head for the cams so it really doesn't seem that a whole lot of pressure is required, as long as it is fed to the bearings. I may end up tapping the end of a banjo bolt and fitting a soldered up carb jet and fit that to the head.

[pete376403]

Ball bearing turbo or plain bearing? I have no experience with ball bearing turbo but I would expect you would want as much (within reason) pressure and volume to a plain bearing turbo as you can get, as long as you have a big enough drain to get the oil back to the crankcase. Likewise with the head if they are plain bearing cams, get the oil out of the head and back to the cases. Smokey Yunnick wrote a book about "Tuning the small block Chev" which had a lot of good info about oil flow through an engine and how little is actually required in the bearings and how to get it back into the the sump, away from the crank and how much parasitic drag oil will add to anything rotating

[Grumph]

The oil drain on mine is from just below the top edge of the head casting down to the flat plate covering the unused half of the cases. Return is well away from rotating pieces.
Mike's problem is only temporary. Once the turbo is back on it, the excess oil has somewhere to go and the head doesn't overfill.
Because mine is running unblown and there is a definite lack of drainage capacity I added the drain.

[speedpro]

Both turbos are plain bearing. The guy at the speed shop was pretty definite about restricting flow to the turbo. He said too much would cause a problem draining and oil would seep past the seals and cause problems. With the 1mm restrictor in the turbo oil feed line the pressure at the turbo can't be very high given the probable reasonably free flowing bearings of the turbo. So far that side of things hasn't been a problem. The Z1 turbo is probably only getting maybe 5psi. Supposedly the old Rajay turbos were very tolerant of low pressure oil supply. Ball bearing turbos would need hardly any oil I imagine, especially a watercooled version. They'd be similar to aviation turbines in that regard, maybe.
On the Yamaha twin both the head and the turbo are fed from the main oil gallery. I currently have a gauge on that and see 60psi. The head is fed from the oil gallery via an external line. Normally one banjo bolt has a restrictive orifice of about 1.1mm. In my case, with the turbo fitted, the banjo bolt that screwed into the main oil gallery is a free flowing double fitting. The restrictions are in each supply line, to the head and the turbo so each restriction saw 60psi from the gallery and reduced flow. Neither will have an effect on the other as any flow diverted from the main gallery will be compensated by the pressure bypass valve in the bottom of the cases which will maintain the oil pressure by reducing the bypass to compensate.

[pete376403]

Another useful book of information is by Hugh MacInness, who was the inventor of the Rajay version of the floating turbo bearing.

I have this book somewhere and pretty sure it doesn't say anything about restricting flow TO the turbo, only making sure that the drain is correctly sized and unimpeded as, in his words, the oil coming out "looks like dirty whipped cream and flows about the same"

https://www.amazon.com/Turbochargers-HP49-Books-Spark-Ignition-Applications/dp/0895861356/ref=pd_sbs_1/140-6800725-7928807?pd_rd_w=n5Hu8&pf_rd_p=3676f086-9496-4fd7-8490-77cf7f43f846&pf_rd_r=W6A8YXTPP3QFQDTTV9C3&pd_rd_r=35374f8b-8ac3-4801-b8f3-1669fc87c9b9&pd_rd_wg=QKjsP&pd_rd_i=0895861356&psc=1

[speedpro]

The original turbo I bought was a Rajay. I was going to put it on an XS1100 in about 1979. Things changed and it ended up on my McIntosh Z1. Z1s have a roller bearing bottom end and the oil falls through the bearings with practically no hindrance. It only proves how little oil is actually needed for the cam bearings. IIRC the oil pressure was something like 2-3psi at 3000rpm. With the restrictor it raised pressure for the turbo at the expense of restricting flow to the rest of the motor. If you were silly enough to connect a light to the pressure switch, the light would be blinking at you every time you opened the throttle and most of the way down the back straight at Puke. Despite this there were no obvious problems with supply to the cam bearings. I have got a baffled deep sump. The baffle is hinged and only restricts oil movement to the rear.
Depending on the restriction of the IHI turbo bearings there may not be much in the way of oil pressure at the turbo. There will be plenty of oil, as much as can pass through a 1mm hole at 60psi.

[pete376403]

Getting a little off topic here but WRT cam plain bearings - KLR650s also have a full rolling element bottom end and can run on an oil mist, much like a two stroke. The cams are plain bearing and will fail to the point of killing the cylinder head while the bottom end just keeps on going, for some time after the motor runs out of oil, which it is wont to do because of marginal piston ring design coupled with insufficient drain back holes behind the oil ring. A lot of thought and effort has been out into reducing the crank supply (it gets far too much, which ends up on the cylinder walls, which the rings cant deal with, so it gets pushed up into the combustion chamber and burnt - so the engine runs out of oil) and increasing the cam supply by drilling out the banjos of the head oil feed pipe. The crank oil is reduced by a restrictor in the crank feed,which also help keep the oil pressure up (so the cams can have more)

So I would take exception to your statement about the amount needed for the cam bearings.

In the case of the KLR, a modified Chev 350 piston fixes the oil problem by 1/much better rings and 2/ much bigger drainback holes.The added capacity (685) doesn't hurt either.

Sorry for going on a bit.

[Grumph]

In this case Mike's not wrong about the cam bearings. The 250 heads have roughly the same total bearing area as an FZR1000 but the spring loads are about 1/6 as high. The bearing load/area is very, very low.
The cam oiling is also very good. The cams are hollow and oil is fed into them with holes at each journal.

[TZ350]

.
This talk about turbos is interesting. As the rules for F4 now allow <70cc turbo two strokes. I have a small turbo and a <70cc cylinder for the RG engine.........:scratch: .... what to do!!

[Vannik]

.
This talk about turbos is interesting. As the rules for F4 now allow <70cc turbo two strokes. I have a small turbo and a <70cc cylinder for the RG engine.........:scratch: .... what to do!!

Sim it, quite an interesting rabbit hole to venture into....

[speedpro]

What to do seems pretty obvious to me.

[speedpro]

holes with rabbits in them, worms in a can, they both come to mind when thinking about a turbo 2-stroke. May as well throw in fuel injection as well.

[speedpro]

Fired the bike up this arvo with the main fuel map axis set to TP/Revs. After an initial reluctance to get going it seemed fine and was quickly tuned to have reasonable lambda readings at the ranges where it was running. It was very snappy on the throttle. I still need to adjust the 0% throttle settings above idle rpm as it goes very lean. Carburetors do the exact same thing so I'm not too worried from an engine protection perspective. I need to do it at the lower rev range before I start finessing the cold start enrichment which are all % increases of the base value in the fuel map. Throttle Position(TP) is way easier to tune than MAP on this engine. Idling at about 4,000rpm it has about 70-80 kPa manifold pressure(MAP). The MAP immediately goes to 100kPa when the throttle is blipped which is normal atmospheric. The only time MAP drops below 70kPa is when the throttle is closed above idle rpm. It's easy to see why cold engines get abysmal fuel economy. The enrichment percentages are large. Once over the initial startup, which sees something like 200% increase in fuel, it settles to something like 45-50% extra "post-start" which decreases over about 4 seconds, and settles on about 20% extra for warmup which decreases as the cylinder head warms up. Short trips where the engine doesn't really warm up are going to be bad for economy.

[Grumph]

Bad for economy ? Wash your mouth out, it's a race bike isn't it ?

The definition of a race bike is - A faster way to spend money.

[F5 Dave]

Your magic white rabbit
Has left it's writing on the wall
We follow like Alice
And just keep diving down the hole

You can't fix your broken promise
Our ties have come undone
I will not be used to be battered and abused
It's the reason why I choose to cut my losses
Your lies fool no one
Your magic white rabbit
Your white room straight jacket

You can't offer your poison to me
In your kingdom of filth
White Rabbit
Straight jacket

[Grumph]

Please advise what you're on Dave - i want some.

I've used some of those Chinese cable ties too - they do come undone. Use name brand ones.

[F5 Dave]

The love of Jesus . :devil2:

[husaberg]

Please advise what you're on Dave - i want some.

I've used some of those Chinese cable ties too - they do come undone. Use name brand ones.

some pilsner

[pete376403]

The cam oiling is also very good. The cams are hollow and oil is fed into them with holes at each journal.

That exactly the same as the KLR. Oil enters the head from a pipe at the back of the head, goes to the left side inlet cam journal and is piped across to the ex cam. It is always the exhaust cam, right side journal that dies when run out of oil as it is the last to get oil. I have a rooted head (bought it that way) which I might try to salvage one day

[husaberg]

off topic but early 80's Hondas had cam bearing issues when they ran plain cams without line boring the tunnels to save $$$$$
thats also why you dont put in lab seals in say a kawasaki three without doing the same.

[speedpro]

Mate Kevin has welded up one banjo bolt and drilled a new 1mm hole. We used pin gauges and determined that the hole was actually 1.3mm. Halving the area would have needed a .9mm hole but I added a small amount to be cautious. It's on the bike now and the 2nd banjo bolt with the smaller orifice has been replaced with a regular one so the only restriction is the modified banjo bolt. Dyno time is this Wednesday. Hopefully everything goes well. Kev is lending me his van again to get the bike to the dyno. I have a few electronic bits that aren't waterproof just hanging off the bike so it's a good precaution given the possible weather. I'm hoping to get video of it running and hopefully at some revs. I'm expecting less than 20hp given that it is half of an engine rated at 40hp

[speedpro]

Got a fuel pressure regulation problem which might be at least part due to alternator problem. Apart from that last night on the dyno went reasonably well. Got a peak of 20hp with a nice spread. Motor revs clean all the way to 18,000rpm but I have to check that in the logs. I was only going be the tacho.

[F5 Dave]

And much was written about yamaha tachos in those heady revs days

[speedpro]

Little video here: https://www.youtube.com/watch?v=rWBPONb0hyg

[Grumph]

Sounds nice and clean. What was Rob pointing out on screen ?

[husaberg]

Sounds great way quieter than i thought
how louds the induction?

[speedpro]

My guess is that the induction is nearly as loud as the exhaust, certainly from where I am. Rob may have been pointing to a speed difference we were seeing for a bit despite being in the same gears and similar revs. There was also a decrease in measured horsepower with no obvious cause. We suspected tyre slip but the loss was very consistent. The last runs looked OK if I remember. For a while the graphs also had an odd shape to the torque curve. I'm going to run it in the garage tomorrow to go over the charging circuit and I will also be checking the coolant. I had to add quite a bit to top it back up, more than I would have expected to need just for expansion alone. I'll sort out a better catch tank or maybe something just for testing in the garage.

[speedpro]

I have a late model alternator rotor but am still using the original 2KR stator. The stator measures up at a fairly low resistance from one lead to another which is no real surprise. The reason I was measuring is that there is no output from the alternator. I can't find a parts fiche online to compare stator part numbers for early and late models, but I suspect that the later model rotors may have a different magnet layout which does not work with the early stators. I'll be looking at it a bit closer tomorrow but if anyone has any knowledge of these parts I'd be interested in your input. I also have the old problem of water being blown out of the radiator and a small amount of bubbles. It didn't look like much running it on stands in my garage but I'll be following up on that problem tomorrow as well. i'll be testing for blowby as per last time but it is pretty obvious, and disappointing. I do have another stator in my box of bits so will see if they look or measure any different tomorrow.

[Grumph]

I think you took all my stators but there's another rotor here. I'll pull it out and check the numbers on it. If it's different to what you've got you're welcome to it.

[speedpro]

It definitely has a very small leak between #1(was #3) cylinder and the water gallery so the engine is coming out again to see what the problem is and how to fix it permanently. The alternator rotor on the engine has 12 points inside where a screwdriver is attracted to it magnetically, versus only 6 for the original 2KR rotor and another that I have here. I need to use this rotor because it is the only one that will fit on this crankshaft so that leaves me looking for a late model 3LN stator that will work with this rotor. I need to have a look around to see what the difference is and how to identify the stator that I need.

Or as Grumph has suggested I might need to swap the new boss into the old rotor.

[Grumph]

How did the numbers match what you're already using ?

[speedpro]

Got it figured out. I need an 18-pole stator from a later FZR250. It looks like 18-pole stators are common on lots of bikes and were used on all the later 3LN model FZR250s.

[husaberg]

The rotor i sent you mike, (with the broken crank stub still attached) was off the broken cranked FZR 3ln that Greg engine now has. cant remember if i sent you the stator as well if i didn't Greg will have the matching stator?

[Grumph]

The rotor i sent you mike, (with the broken crank stub still attached) was off the broken cranked FZR 3ln that Greg engine now has. cant remember if i sent you the stator as well if i didn't Greg will have the matching stator?

No. The stator was probably damaged - but wasn't with that box of bits. Mike's onto other sources.

[speedpro]

I took the cylinder block to Kevin's and tested it with flat steel. One sleeve is still proud of the top of the block and the other has dropped a very small amount and is probably flush. We didn't run any gauges over it but it is definite. The plan is to skim the tiniest amount off it like last time to make the whole thing flat including the sleeves and then take .001" off the alloy of the block. I may start putting it back together late tomorrow afternoon but I'll probably still be cleaning things tomorrow.
With the top end apart there are no obvious problems. The cam bearings look good and there was lots of oil in the head so the restrictor looks to be about right.
I just need to find an 18-pole stator and it will be all good.

[dr gonzo]

Speedpro!

I read you build the tzr 250 chassis the mb100 engine. Before you race the mb5 chassis.

What is the Big advantage the tzr chassis, and what is the disadvantage the mb5 chassis.

Handlig, Weight, corner, lap times or other...?

Thanks the informations!

[dr gonzo]

Hello Speedpro!

You bulid the tzr chassis the mb 100 engine, before you use stock mb5 chassis.

Whai is the advantage the tzr chassis vs mb5 chassis? Or disadvantage mb5 chassis?

weight, handling, laptimes, etc...

Thanks the informations!

[F5 Dave]

As someone who used to race an ever evolving MB50, I'll offer an opinion. The MB50 frame and everything touching it is shit. It would be cheaper to find another donor chassis.

[speedpro]

F5 is correct. Look for the latest chassis possible with the best suspension and brakes. Weight is obviously an issue for a 50. If you are allowed and if you can find one, an old RS125 chassis is the ultimate. There have been huge advances in tyres and you will need to be able to fit new 17" tyres, and to fully utilize them you then need suspension and frame that is good enough, or at least closer than an MB50 chassis

[speedpro]

My original chassis was a very modified RG50 chassis that handled like shit. The FZR chassis was so much better it's hard to describe. The downside was that it weighed lots more. Despite that I would have been faster everywhere on the better chassis. A couple of other small bikes I have ridden were the Steadman's Kawasaki 100s. Jim's bike in particular handled superbly and being a small farm bike chassis was reasonably light. Jim had swapped in 17" wheels and a decent front brake. He also did a lot of development on the suspension.

[F5 Dave]

That is Honda RS125, in Europe the Aprilia might spring to mind but their RS125 is a totally different beast.
For giggles put the MB front wheel between your knees and twist the bars. Alarming isn't it?

But don't then become fixated on trying to fix that. The rear suspension will hold everything back even if you were silly enough to brace the frame, convert ally box swingarm, rework upper triple clamp, brace forks, Arrgh waste of time, as I found out.

[Grumph]

I'll endorse what Dave and speedpro have said. We ran what was basically a braced MB50 chassis and swingarm with CG125 front end powered by a good MB100.
I got it to the point where it was reasonably directionally stable on bumpy street circuits - but still a handful. Quite successful with an extremely good rider but hard work.
Another alternative chassis is the CBR150. Right size rims, good suspension - and they blow the OE engines comprehensively. i was offered one and was surprised to see how close to an RS125 it was. Might be a bit more common in some areas of the world.

[speedpro]

Back on topic. Machined the block again today. I took a bit off the top of the sleeves to get them all level and flat only to find that the last 2 passes were only taking about 1/2 the red felt tip marker off that i had covered the surface with. I had the raise the block probably .0005" to get a clean cut right across the top of both sleeves. After that I raised the block another .001" and took material off only the aluminium which has left the sleeves just that little bit proud. After measuring it a bit better after work was finished it turns out the block has a taper of about .002" side to side. Next time, which hopefully won't be later this week, I might square it all up.

[Grumph]

What squish clearance have you finished up with ?

[dr gonzo]

F5 is correct. Look for the latest chassis possible with the best suspension and brakes. Weight is obviously an issue for a 50. If you are allowed and if you can find one, an old RS125 chassis is the ultimate. There have been huge advances in tyres and you will need to be able to fit new 17" tyres, and to fully utilize them you then need suspension and frame that is good enough, or at least closer than an MB50 chassis

I use aprilia rs50 fork, nsr 125 triple clamps, cone bearing, aprilia 50 supermoto wheels and brakes, bitubo rear shocks, and mtx rear swingarm, the honda mb frame.

I have must use the steel frame, because the local racing rule write it.

[F5 Dave]

Start another thread perhaps?

[speedpro]

It does sound interesting and a separate thread would allow others to provide advice without it getting lost in this one. Start out by posting a few photos and a description.

[speedpro]

I've buttoned up the motor, again. There's just a couple of cover plates and the like to go. It's so easy once all the parts have been sorted.
I have been looking at how to sort out the alternator. Overnight I thought about rewinding an old stator I have here in such a way that it would work with the new rotor. I had a careful look at how everything fitted and found that the new rotor is about 5mm larger ID than the old which will result in a larger gap than I'd want. This leaves me 2 choices - 1 install a late model stator or, 2 transfer the old rotor onto the newer hub. I'd prefer a new stator and have found one on AliExpress supposedly for a TTR250 which looks very close. It has a diagram with measurements which is useful. I've also found that despite what the wiring diagram shows, the stators I have for the engine are all delta configuration, not star.

[F5 Dave]

Have you done a genome sequence?

[speedpro]

The engine is back together and in the bike. I'm planning a small job on a water pipe and it will be done. I have gone ahead and ordered a stator I found that is close to, if not exactly, what is needed. I ordered valve guide seals at the same time. Funnily both were listed as being for TTR250 motorcycles.

[husaberg]

The engine is back together and in the bike. I'm planning a small job on a water pipe and it will be done. I have gone ahead and ordered a stator I found that is close to, if not exactly, what is needed. I ordered valve guide seals at the same time. Funnily both were listed as being for TTR250 motorcycles.

A very quick google suggests 3.5mm stem for FZR and 5.5mm for TTR250?



https://ae01.alicdn.com/kf/H6143e46f3b804b9084e9d729d3575cc4F.jpg

https://ae01.alicdn.com/kf/HTB1YYWWcwmH3KVjSZKzq6z2OXXap.jpg
https://en.impex-jp.com/catalogs/moto/yamaha/fzr250/2kr0-1987-silky-white-sw-00ge-japan-2497/valve-s-101445.html
https://www.partzilla.com/product/yamaha/1HX-12119-00-00
looking at the fiches here it seenm the 2kr ones are the same s yzf600
Yamaha Power Equipment EF1000IS CAMSHAFT/VALVE
Yamaha Power Equipment EF1000ISC CAMSHAFT/VALVE
Aftermarket Parts Engine Valve Train Valve Seals
Yamaha Motorcycle 1995 YZF600RGC Valve
Yamaha Motorcycle 1996 YZF600RHC Valve
Yamaha Motorcycle 1996 YZF600RH Valve
Yamaha Motorcycle 1999 YZFR7 - YZFR7L Valve
Yamaha Motorcycle 1995 YZF600RG Valve

the 3ln ones seem to only be 3LN
https://en.impex-jp.com/catalogs/moto/yamaha/fzr250.html
https://en.impex-jp.com/catalogs/moto/yamaha/fzr250/3ln3-1990-silky-white-sw-00ge-europe-2478/valve-100494.html
https://www.fowlersparts.co.uk/parts/view/3LN-12119-00

i can't even find a 3.5mm valve in the TKRJ list

What did you use Greg?

[Grumph]

Pretty sure I went through Don's stock until i found something that would do. He was Pitlane in ChCh and still has a heap of stock boxed when they did the post quake clearout. Pack of 10 of which i used 8 and don't even know if I can find what was left over. yamaha seals are a pain. What's listed for the 250 doesn't fit and the same goes for some 400 versions too.
I'll have a look tomorrow.

What stem size are the 750 and 1000's ?

Edit - these may even have been for Honda. I believe the 250/4's use 3.5mm stems.

[speedpro]

This is the listing: https://www.aliexpress.com/item/1005001848449062.html?spm=a2g0s.9042311.0.0.60fd4c 4ds4J7JV

16 valve stems in the set so not any TTR250 that was ever brought to NZ. Cheap as chips so worth having a look.

[speedpro]

10 days from order to being delivered.

[speedpro]

Oh well, it was still worth checking out. They fit 4mm stems so will be good for the 2KR version.

[speedpro]

I'm going to fit a Davies Craig water pump, an EBP-15, the same as on my scooter. Supposedly they are good for up to a 500cc bike. This will allow the removal of the Yamaha water pump and a tidier routing of water hoses which at the moment have a pipe exposed on the left side. I'll wire it up to the fuel pump circuit so that any time the fuel pump runs so does the water pump. Supposedly the local distributor has it in stock. I've also been working on all the little things need to go racing, which is taking longer than I thought it would.
With plenty of spare time I have been able to look at the ECU setup for when the turbo goes back on. I'm pretty sure I have it sorted out now. Once the main fuel map is sorted properly it will just be a matter of tuning another table so a certain % is added depending on boost and revs. Easy.
I haven't even looked yet but I expect there will be some sort of similar setup for the ignition.

I have noticed that Link have a default trigger setup for the engine in my car. I was thinking the other day how the car is a bit wimpy.

[speedpro]

3D printed a mounting flange for the electric water pump which I have decided to mount directly to the coolant port on the cylinder block. I need to make a proper alloy flange. I have wired a connector to ground and the fuel pump supply so whenever the fuel pump is on, which is when the engine is running, so will the water pump. I'm going to use the ECU to control the boost and have a solenoid bypass valve which I will wire to a spare aux output. I was going to use ignition 4 output which isn't being used and can be reconfigured as an aux output, but have decided to use a dedicated aux output channel. I imagine it would be quite handy being able to reconfigure unused ignition and fuel injection channels as aux outputs. I'm sticking to basics as much as possible but it's interesting what the possibilities are. I still need to figure out what's required to control the boost in the way of tables.

[speedpro]

I ordered an alternator stator(18 pole) for a newer FZR250. I'm now using a crank from a very late model FZR and the old stator does not work with the rotor that fits the crank. Supposedly the stator left the country of origin on 27 August but hasn't been logged at the next point. Seems that it may be some time. Batteries alone aren't going to work with the ignition, fuel pump and the yet to be installed electric water pump and boost control solenoid. If anybody has an 18 pole stator for a late model FZR250 I'd be very interested.

[speedpro]

I have been looking at wastegate control. I was hoping to use the ECU in closed loop mode which would have been complex to configure but would have meant precise control. Unfortunately it seems the base model ECU I have can't do closed loop but is limited to open loop. In the configuration help file it seems to control the wastegate on a throttle position versus rpm basis with no account of the actual boost value. I emailed David from Tune Technic who I bought the ECU from and he came back with a suggestion to put Manifold Gauge Pressure(MGP) on one table axis and RPM on the other. The table values are the amount the wastegate is opened effectively. To me this makes it more or less closed loop. Values are entered in the table below the desired boost that result in the wastegate remaining closed. As boost approaches the desired value the table entries result in the wastegate progressively opening. The boost control solenoid has a pulse width modulated(PWM) signal applied which opens a bypass valve an amount depending on the pulse width. Failsafe mode is fully open which will pass manifold pressure to the wastegate without restriction. I can see this working really well with the wastegate closed until boost closely approaches the desired value. This will assist with spool up. I know with my big bike that this can really help. With boost on the big bike set to 12lb the turbo spooled up a bit slower from about 8lb. With the wastegate set for 19lbs boost the turbo spooled up to 14-15lbs really quickly as the wastegate was completely closed until then. Fun day at Taupo running 19lbs boost. The front wheel would not stay on the ground over 6000rpm in any gear.

[husaberg]

I always wondered what Ryan Martin and Justin Shearer was talking about when he wanted to check the CO2

https://www.youtube.com/watch?v=LyOhfDw54zo

[speedpro]

I went through all the MB100 bits I have. It's reasonably obvious that MB100 rods have a fault. You can see from the 2 rods in the photo that they have both failed more or less exactly the same.

[speedpro]

I have another bin full of gearboxes and clutches plus a couple of pipes in other places and a 34mm carb plus a 36mm carb on the shelf. Sort of wondering what to do with it all.

Some of these bits belong to Gary Cunningham.

[F5 Dave]

Ooh, he is hard on gear.

I snapped a rod when my foray into yz100 pistons using adapters failed and a couple of crank pins with steps. But that was it. Was getting no where near 13,000 though.

[koba]

If you want to get rid of any of that, I'd be keen to buy some stuff.
I'd expect I'd actually use it eventually, or set someone else up to do so.

My main focus now is Dave's 100 and I'm sorted for that for years but have a few slow builds for learner club bike stuff ticking along too.

I have a Derbi made from Gary's old stuff.
That goes (really good!) Just needs a pipe of it's own (I've cut up a kart pipe to start with but it's a bit wrong).
I've got all the stuff to build another one too but will probably hand those off to someone to build up.


Sent from my Nokia 6.1 using Tapatalk

[koba]

I went through all the MB100 bits I have. It's reasonably obvious that MB100 rods have a fault. You can see from the 2 rods in the photo that they have both failed more or less exactly the same.That is really interesting!

I've not had any failures like that but also probably less revs, 12500 over rev for the red bike that I've done most of the time on.
That's using standard pistons still so built to suit the big thick rings.

Sent from my Nokia 6.1 using Tapatalk

[speedpro]

The Track & Trace on the new stator has been saying it left China for over a month and no further progress. It arrived this morning :clap:

[husaberg]

Read something interesting the other day in an old old classic mechanics of the 1980s
it was honda admitting they f-ed up the stator side bearing on the MB5 It miust have been sht as bearing mind i am pretty sure their version was a weak as piss restricted 30mph.
turns out they clearances it wrong from the factory it don't even think it was a proper c3 makes me now wonder if it was the same on the H100 and MB100
I killed at least two with factory bearings.
I killed one and a stator at the Last Wigram where you won.
My son wants to go racing i seen a MB100 for sale the other day i was almost tempted.
But fuk supersport 300 is likely more fun less fetiler.

[F5 Dave]

I killed several big ends because I was on a budget and kept finding $70 engines that had been sitting. Of course 2 would have paid for a rodkit and labour to press a crank.

When I finally did I got a Longrod kit. Mike will tell you happened. The Honda rod was the same price as the kit and another $25 bought the bearings and washers.

Slow learner.

[speedpro]

Standard MB100 piston and ring in my sidecar was good for 14,000rpm. On the dyno it revved to 14K all the time. Originally it lasted 6 years and saw plenty of racing. Every now and again if you pushed it a bit a tip would fall off the ring. I only used one ring. Pretty sure original MB100 main bearings were C2 clearance. I always replaced them with C3 and went to C4 on the good motor.

[F5 Dave]

And yet the MB50 once you hit 12,000 a few times would lose a ringtip and fall right off power straight away.

[speedpro]

Woohoo! New stator arrived from China. After a bit of fiddling it has been fitted and is generating electricity.
I made a little video about the stator and balancing the rotor after the long tooth was reduced in length. As per the old 2KR rotor this newer 3LN rotor was out of balance before I modified it and modification made it worse.
I have also converted the cooling system from the mechanical water pump to an electric pump the same as in my scooter. It's a Davies Craig EBP15 made by Bosch. There's a little video about that as well. The whole cooling setup is a lot tidier now and doesn't have the pipe from the pump sticking out the side acting as crash protection. there's also a small video(with sound) about the cooling system.

Alternator video is here: https://www.youtube.com/watch?v=L7_gwmGjHGs

[speedpro]

Big change for today. The FZR frame I got from ESE is not needed by Kevin as his involvement with the 1/4 midget is ending and there will be no need to dyno that engine. I've decided to put an MB100 engine in it and have it as a spare for anyone to ride. I have all the bits and just need to put it together. As part of that process I have a bit of machining to do. Due to changes in stroke, rod length, and piston height I need to take something like 3.6mm off the base of the cylinder. I squared up the top of the cylinder as well which was a tiny bit off. The photo is of Kevin's adjustable mandrel in his lathe. The shaft has slots cut which have varying depth from one end to the other. In each slot is a wedge with a similar taper which makes the outer face of each wedge parallel with the length of the mandrel. There's a collar at each end that is used to push the wedges back and forth in the slot which has the effect of varying the diameter. Soooo easy to use. Jam it in the lathe, slide the cylinder on, tighten one collar until the cylinder is wedged tight, and nip the other collar up. It sticks out a way so I put a centre up it as well. Perfectly square every time and no setup.

349831

[speedpro]

I'm making a bit more progress towards putting an MB100 engine together. It shouldn't be surprising that there is a bit of work to do before an engine can be assembled from parts I have lying about. I'm not being too serious about this build, I just want an engine that is reliable for the spare bucket I'm building that other people can take for a ride. Having said that it will be asembled properly with squish clearance set correctly, and so on. One thing that is required is to relocate the head properly so that the combustion chamber and squish are centred on the bore which it isn't at the moment. Small video, part 1 - https://youtu.be/l3tlupvNCk8.

[speedpro]

Back doing bits on the FZR. I decided to change the plenum inlet from the small tube and to mount a flange. To the flange I am able to mount a throttle body if/when I get around to it, or as in the photos just fit an airfilter for when I run it normally aspirated like now. This adaptor is 3D printed PETG and seems pretty tough. The inside steps down with a similar shape as the entry on Mikuni carbs. The outside is shaped to allow the fitting of the cap screws used to mount it.
In the future I want to try a single throttle body between the turbo and the plenum and I've been putting a bit of thought into the design. The way it is usually done with a disc mounted on a shaft has always looked like a quick and dirty way of doing it to me. I don't like the screws in the intake though I understand they very very seldom cause problems. The shaft with screw holes in it is also a weak link in my opinion. V-rods can have issues with the shafts for instance. Some sort of a slide valve was considered but I think stiction might be an issue and having it slide on rollers increases complexity too much. A ball valve has a few downsides for me as well. What I have thought of is having a shaft with a disc but made as one piece which would allow it to be aerodynamically shaped and also hopefully completely reliable. This would of course require a 2 piece throttle body which would simply be 2 pieces with a hole bored down the middle and a couple of holes for the shaft to pivot in. I really can't see why this hasn't been done before. Maybe I just haven't seen it.

349849349850349851349852

[Grumph]

The reason you haven't seen it is because the myriad of subcontractors to carburettor companies can supply the split shaft and butterfly at a price and quantity you couldn't match with the one -piece. And designers of multiple carb/throttle body assemblies have to think about fit and tolerances with unskilled labour on the line.

It'll work. Either two identical cast/3D printed sides or one an inlet stub and the other a bellmouth. At this point I'd remind you that John Britten cast his throttle bodies in what was basically carbon fiber filler material. Ultra light and machined well. Dirty with dangerous dust though.

[speedpro]

Bit of a side note, the MB5 now has a new home

[speedpro]

Plenty of spare time so I have been learning Solidworks software. As an exercise I've designed and printed a throttle body that could be used on the bucket. The rectangular opening in the middle is 30mm on the sides and 36.58mm at the widest top to bottom. The round bits each end are the same size as the turbo and the other bolts to the plenum. The blade in the middle is aerofoil shape and the square section is shaped top and bottom to match the blade profile approximately so as to maintain a reasonably constant x-section for the length where the blade is. It needs rework if it's going to be made from aluminium and also needs to be split down the middle to allow for machining of the interior. The next struggle is getting a curve in the tapered sections at each end.

349937349938349939349940

[speedpro]

The MB100 powered FZR chassis is slowly coming together. The engine is together and in the frame and I've been through my bins of bits and extracted a throttle body, clutch lever & cable, and chain. I also found the little sprocket required when running an MB engine which I have fitted after machining the sprocket mounting hub so the chain does not ride up on the sprocket bolt bosses. The chain I have is a crusty old RK 428H. I have links for other chains but this one has beefy side plated and none on the links I have will fit. I've also been through the carbs I have and they are either tiny or huge. If anyone can help with a carb in the range 24mm to 32mm, preferably 28mm, I'd be interested. Failing that I'll purchase a new 30mm Mikuni VM round slide. The 30mm looks to have a newer design body compared to the 28 and is also a bit bulkier which will allow machining for inserts. I'm also after a front master cylinder if anyone has one they don't want. If anyone has a link to one that works can you send/post it and I'll check that out as well. Thanks.

[F5 Dave]

I'll have a dig in carbs. There was a PWK I never got back, but might have bits for another.

[F5 Dave]

Meh pretty slim pickings these days, I sold a bunch a way back to release some funds.

There's almost a TZR carb but missing Float jet and seat, needle and emulsion tube but that will be it in the bag with a shroud fitted as experiment.

There is however an RZ carb by the looks so 26mm pj needs the pj tube or blocking off more like. Have a Yamaha reedblock needs reeds, heck I may have fibre ones now I'm back upstairs, and an inlet manifold.

Bah pic won't load will try on tablet later.

Anyways yours if you want it or either.

[speedpro]

There looks to be something usable in the carbs Dave. I'll give you a call tonight.

[husaberg]

There looks to be something usable in the carbs Dave. I'll give you a call tonight.
i think i might have a throttle cable to suit the long mount those TZR carbs normally have if it helps

[speedpro]

I've been slowly chipping away at the spare bucket. Latest little project was sorting out the gearchange. I looked at simply fitting a reversed lever but it would have been either too short or not left enough room for your foot. Modifying the original footpeg mount, footpeg, and fitting a lever got too hard real quick. I ended up making a new footpeg bracket and then making a whole new linkage. It all came out pretty good and I'm happy with it. Just need the welding finished on the lever as it is just tacked on to check placement.
The countersunk hexagon socket screw had the head diameter machined down and also a couple of mm taken off the face. The bush it fits into I then machined a matching recess. The screw goes through the 2 bushes and screws into the bracket and has a locknut on the back. The bushes when bolted together have clearance to allow the lever to pivot. One little problem which complicates adjustment is that each end of the rod has left hand threads to match the bits I had lying around. Also, I could probably bend the lever to completely clear the rod or what I might do is put a slight bend in the rod. It's a good grade of stainless so it won't affect the gearchange by flexing.

[speedpro]

It all went together quite nicely

[speedpro]

Carbs arrived from Dave today. I need to check for spares that I have but it looks like I'll end up using a Mikuni VM 28mm round slide carb, possibly feeding a plenum. I'll probably just get it going first.

[speedpro]

Carb from F5 Dave has cleaned up nicely. Ignition is fitted and the gear linkage is complete and ready to go.

350186

[husaberg]

It all went together quite nicely
what sort of rose joint are those?

[speedpro]

what sort of rose joint are those?

As far as I'm aware they are standard off some Jap bike. No idea what. They come with a rubber boot over them.

[speedpro]

I've been busy on the spare bucket. The front brake is coming along and I've finally got a caliper and master cylinder I'm happy with. I've also decided to try just running with 3 bolts attaching the disc to the wheel. I've heard of other people doing it so it should be OK.
350201

[Grumph]

I've been busy on the spare bucket. The front brake is coming along and I've finally got a caliper and master cylinder I'm happy with. I've also decided to try just running with 3 bolts attaching the disc to the wheel. I've heard of other people doing it so it should be OK.
350201


I regularly turned away OW01's TZ's and FZR1000's only using 3 bolts per disc when scrutineering in the late 80's and 90's.

The weight saving and possible time saved changing wheels does not offset the higher risk of running half the OE fasteners. On big bikes anyway.
Depends on how picky your club scrutes are. The 250FZR chassis ex TZ350 had one of those discs thinned to 3mm. A stock one went on for big track use.
I'd pick that the thin one would have warped after a couple of laps of Ruapuna or Levels.

[F5 Dave]

Have a look at the picture Greg. Made me larf.

[Grumph]

Have a look at the picture Greg. Made me larf.

Point taken. Subtle.Even a certain OW owner back in the day didn't try that through scrutineering.
His TZ presented without discs and on it's wets got some instructional words from me though.

[speedpro]

Little bit more mucking around making use of what I have. The spare bike top rear engine mount bolt was a bit short for putting a nut on. After a bit of thought I decided to put a helicoil into the sliding sleeve on the left and screw the engine bolt into it. Once done up tight the sleeve could them be clamped in the chassis just like standard. Like most things it turned out to not be that easy. The sleeve on the bike actually had a sleeve inside it so when I tried to drill and tap it for the helicoil the inner sleeve spun and moved. I thought about welding it in place but decided to spin up a whole new one. It came out OK and really is how it should have been done originally. Rob at ESE dropped off a pretty solid old fibreglass seat unit. There's a bit of work to make it fit and to clean it up so it looks presentable. I put a bit of fibreglass in it this afternoon to fill holes previously used to mount the seat and have already adjusted the frame a bit to fit it. There's a bit more frame adjustment to be done yet but I suspect lots of heat may be required at some point.
Hopefully I'll be able to get both bikes professionally painted kelly green. There's the possibility of a third bike joining the ranks so I may see about getting all painted at the same time.

350222350223350224350225

[speedpro]

It's been a long time since I bought good paint for a car. Bought some for the bikes today. $92 for 500ml + 1L of thinners. They better end up fast and there'll be no crashing.

[speedpro]

Getting a few things done. Seat is where it's going to start at but it could probably be another 40-50mm higher. The way I've mounted it will make the change easy, I'll just need thicker blocks of wood. Currently it's 40mm off the frame rails. I've glassed up a few holes and bogged and smoothed others and made a start on the tank. The current black paint seems pretty solid but I'm a little worried how it will react after a coat of the new paint which seems to have some reasonable solvents in it. The seat is pretty solid so I'll cut the rails off just after the new cross brace which is needed to screw the new rear seat mount fasteners into. It's quite relaxing just pottering around on this stuff but it is surprising how much there is to do when you get right into it.

[speedpro]

Small things are getting done. The pipe has been dummied up and little mounting tabs added for the hanger. I still need to fabricate something to hang the pipe on under the frame. The subframe has been cleaned up and "extra" bits cut off and it now has a coat of black paint. The tank and seat have been cleaned up and smoothed a fair bit, good enough for a bucket anyway. I've given them a coat of paint in my carport. Hopefully I'll get the 2nd coat a lot better and it will be a lot glossier without too much elbow grease. The paint looks like it will be a pretty good match with my original FZR. I will clean and paint the covers on the engine with high temp aluminium paint. Everything else looks reasonably good and they are starting to stand out as they are a bit manky.

[TZ350]

.
Looking Good..... :yes:

[husaberg]

Silver wheels?
350328
i never realised greg won Bathurst in a car as well..

[speedpro]

He drove a car like he rode a bike. If the nose was in front then he had the corner. His car racing style was just a bit controversial among the car driving wooses who were used to forcing people wide simply by having a nose up the inside.

[speedpro]

Got a bit more gloss after the 2nd coat. There might even be enough to flash up the old bucket as well. Despite the paint being very "watery" it has very good coverage. The trick seems to be to spray it on a lot thicker than I was at first and to create a wet layer with only 2-3 passes.

[speedpro]

Looking at both bikes together I have decided that what I need is a seat, ideally an FZR seat, the same as on my original FZR. This would raise the seating position to about where it should be plus provide a comfy workable seat when riding/racing. If anyone has a spare they don't need let me know.

[F5 Dave]

I liked doing my work closer to the ground. Kinda depends who you are lining up to pilot these. Young flexible chap wouldn't need such frivolities.

[Grumph]

There's a rough one here which came with the stock subframe used when it was Rob's Beast.

[speedpro]

I liked doing my work closer to the ground. Kinda depends who you are lining up to pilot these. Young flexible chap wouldn't need such frivolities.

The other thing to consider if the stock tank is used is the rider bending over the rear of the tank. Younger leaner riders will be better at it than say the more mature and rounder riders. The higher seat will help with that at the expense of the head down bum up riding position. Me, myself, and I, with our unjoined wrist fracture and crunchy neck have a bit of an issue with that riding position.

[speedpro]

I'm hoping that I might be able to run the bike on an eddy current braked dyno. Still discussing it with a youtube guy who has one. It can do programmed steps or slopes or set speed or rpm so will be perfect for tuning the ECU.

[speedpro]

With no fuel or oil the MB100 engined FZR weighs in at 86K. Not great but not too bad. The tank weighs 5K on it's own??????

[F5 Dave]

That's actually not too bad. I think my H100 steel frame was like 81. Maybe with gas, but not a mile away.

Not a 50 mind.

[speedpro]

It's alive - https://www.youtube.com/watch?v=Edw53VDo-p4

[F5 Dave]

Good to see you cleaned your fingernails before making the vid.

[husaberg]

i like how the exhaust pipe muffler has the same angle as the seat.
350363
In the nov video what is the reed rubber?
350364
Early IT175?

[speedpro]

I'm not 100% sure but I think it's from a RD350. New holes drilled to match the MB100 mounting holes. The reed block is from an RD as well but as you can see I've added a splitter. I also removed the supports between the reeds on each side and fitted a single .4mm CF reed each side. There's a bit of devcon inside the reed block which makes it look a bit smaller but it flows well enough going by the horsepower.

[husaberg]

I'm not 100% sure but I think it's from a RD350. New holes drilled to match the MB100 mounting holes. The reed block is from an RD as well but as you can see I've added a splitter. I also removed the supports between the reeds on each side and fitted a single .4mm CF reed each side. There's a bit of devcon inside the reed block which makes it look a bit smaller but it flows well enough going by the horsepower.

rd350 makes sense slot the top two a few mm wider and redrill the bottom, with those, but i thought you said 32/34mm carb?

[speedpro]

I did run a round slide Mikuni 32mm carb on this setup previously. This time I have a 28mm round slide Mikuni. I expect it will be a bit easier to ride.

[husaberg]

I did run a round slide Mikuni 32mm carb on this setup previously. This time I have a 28mm round slide Mikuni. I expect it will be a bit easier to ride.

okay so you can squeeze in a 32 on the old rd rubber? or did you use another one?
i have been trying to find straight ones to go with the 34 ish Keihin carbs i have fo the LC
i was going to try some Snowmobile ones.
https://i.ebayimg.com/images/g/JnUAAOSwE6dfQmef/s-l1600.jpg

[F5 Dave]

So I bought some billet ones after kit ones split. Then to mikuni spigot type. Had a silly name. Might come to me.

[husaberg]

So I bought some billet ones after kit ones split. Then to mikuni spigot type. Had a silly name. Might come to me.

like these
https://img2.vitosperformance.com/prodimage/ProductImage/1500/7055d839-9b97-4003-99a4-d9e7ee6ff59c.jpg
chariot?

You had the UPP ones that split?

[F5 Dave]

Chariot off Ebay, yes pretty sure. UPP ones split.

Just thinking of course the size is CR250 on CPI barrels, but they do a range I think.

[speedpro]

Back to the FZR125. I've been messing with it a little bit, just sorting out everything so it's good to go for racing. I have the starting all sorted now and can fire it up with the 2nd pull on the back wheel every time now. After taking the cam cover off to torque the head studs and check shims I put it back together. When I first fired it up it had a little oil leak but fortunately after spraying a bit of brake clean around I was pretty sure I found the little gap leaking oil. I super cleaned it and pressed sealer into it and it seems to be all good now. At the moment I'm aiming for Tokoroa at the end of the month. The other bike with the MB100 will hopefully be all sorted as well. It seems to run OK but I would prefer to check it on the dyno rather than risk a problem at the track. 10 year old tyres with 1000s of dyno runs shouldn't be a problem, I'm hoping.

[speedpro]

Change of plans. I am not going to Tokoroa. I was looking forward to riding the bike, it's only been 20 years in the making, and I have the spare bike ready to go as well which anybody could have ridden. My plan now is to carry on and join the EBP Kart club and go to Edgecombe for a play on my own or preferably with a couple of mates, somebody else's mates. I haven't got any of my own. Hopefully the grippy track will compensate for the tyres though given how old I'm feeling lately I'm not expecting to doing much more than puttering around, albeit hopefully at up to 18,000rpm. Hopefully it will be a good turnout and the weather will be good for racing.

[F5 Dave]

Probably wise. Towards has at least 3 corners which are thoroughly 'front endy' as well as broken corner near start unless they've fixed it

[speedpro]

The sensible twin has a new home.
350838

[husaberg]

found the missing rocker cover here if you want one
funny how that chassis made it back to Auckland
One of Robs NSR ones came from me.
now that one which was ex Rob goes to CHCH and back

[Grumph]

The sensible twin has a new home.

Did you find the spare ignition box tucked in beside the motor ?

[speedpro]

I got it. I'm taking #6 to Edgecumbe tomorrow for a bit of a ride. Nervous isn't even close to describe how I feel. I'll give the MB100 powered bike a ride as well.

[speedpro]

The MB100 one wasn't taken off the trailer. It was too hot and I couldn't be bothered after riding the twin.

The twin went reasonably well. It started with the first pull on the back wheel and ran OK. There are definitely improvements to be made to the tuning but it's rideable. It was revving clean right out to the rev limit which is currently at 18,000rpm and was sweet from about 13,000 up with full throttle.

The only little problem was a leaky oil seal on the end of the cam behind the cam trigger disc. It's easy to replace. There was a bit of oil sprayed around on that side of the engine after about the 3rd session.

There's a little video which is a bit wobbly due to being unable to see the screen in the bright sunshine and the camera wanting to focus on the mesh in front of the verandah. The sound is OK.

I have to check it out, do an oil change, and fit a new seal. Hopefully that's it and I'll be able to have a ride at HD.

Link to video: https://www.youtube.com/watch?v=cqPq20fi43o

[husaberg]

Golly it sounds like it only revving to 11k on video?
much deeper note than i would have expected.

[speedpro]

Spent the day at Hampton Downs yesterday. It was the first time on a track for 9 years or so, apart from Edgecumbe a few weeks back. The bike seemed to run OK but still has a slight oil leak somewhere around the head. It's not much but is enough to coat everything on the left.

The bike ran OK but unfortunately with the short notice for at least one race and the time it takes to warm up I was taking it a bit easy at the start of a few races. Only the last one was it warmed up when I went out.

The fuel pressure regulation is still a problem. Most times I turn it on the pressure needs to be adjusted, sometimes up and sometimes down. Despite having run it on the dyno and got the fuel map in the ballpark, at 100% throttle it was still lean around 13-15,000rpm. It was REALLY lean according to the log so a bit surprising it ran as well as it did. Definitely not quick but it ran OK. I did check the fuel pressure at one point and found it a bit low so adjusted it. The data log for the next race shows the AFR not as lean so the leanness may simply be a fuel pressure problem.

Interestingly, Ellie to whom I sold Cricket's CB125, was on track in the same class. There was very little difference between the 2 bikes. I was glad to see the CB going well. I'd fitted a 150cc kit and done a bunch of machining to get things just right and i always had a nagging worry that it might go "boom" but it was going really well, even the gearing was more or less spot on for HD.

Anyway, it was a good day. There was a good crowd of various bikes and a few new and newish bucket racers. I think Ellie has only been to one other meeting, I was back, and the 2 guys sharing an FXR, the old club bike, were parked next to Rob and I. The weather was near perfect and as far as I could tell everyone had a good time, with maybe one exception, being the person taken away in the ambo.

[speedpro]

I've been looking at the fuel supply system due to the variation in pressure I've been seeing. I've tested the system by setting the pressure regulator to 3bar and then applying compressed air through an air regulator to the fuel regulator. With about 8lbs boost pressure the fuel pressure rose to about 3.5bar which is about right. It turns out that the pump will only push about 4 bar max which means the fuel pressure will only be compensated for about 1bar of boost. That might be enough or it might not. I can of course run it over 1 bar boost without fuel pressure compensation as long as the injector duty cycle doesn't top out. I set up a test rig with a spare fuel pump I had which I thought was only supplying about 1.5 bar fuel pressure. It turns out the pump supplied 4 bar when asked so it seems OK. The problem was probably the regulator. The original regulators have a plastic body with a metal capsule clipped in. There are a couple of o-rings that seal things and I know that the little one had a habit of leaking. If I get bored I might look at machining an alloy housing for the capsule with the "open-to-air" end of the capsule sealed in and supplied manifold pressure. There are holes in the capsule so it is another possibility for a rising rate regulator. One disappointing thing is how the pump speeds up when the battery voltage is boosted and how the pressure rises with it. The good thing is that the data log shows the battery pretty consistent when the engine is running so hopefully the fuel pressure regulator can be adjusted with the battery voltage at 14v and it will be consistent while the motor is running. If anyone knows of a small EFI fuel pump that is capable of pumping say 50hp worth of fuel I'd be interested in having a look.

[speedpro]

Dyno time was interesting yesterday. Right at the start there was a little problem with water not circulating. I figured it was the water pump. Although it is mounted near the bottom of the water circuit it is still possible for air to be trapped inside the pump housing as the feed hose rises up to the pump and the outlet is at the bottom of the housing. Rob and i rolled it back out of the front clamp and leaned it each side until the air was pumped out. After that it seemed to be fine.
The fuel pressure regulator is definitely not very stable. Initially it was more or less 3BAR but as the session went on I had to screw the adjuster in to maintain pressure. This morning when I ran the pump here at home the pressure was 4BAR. It's hard to determine what is causing this but I suspect it is related to fuel temperature and possibly the regulator diaphragm. I ended up adjusting the fuel pressure 4-5 times through the session for some sort of consistency.
There is a table in the Link ECU where you are able to enter desired Lambda values at different throttle positions and RPM. I've simply entered values that will see the engine running a bit rich and hopefully safe. What I did on the dyno was hold the throttle at 10%, 20%, 30% and so on and let the engine revs rise at each setting. The ECU logged the actual Lambda and a report can be displayed showing the difference between desired and actual Lambda at each RPM and TPS position. A simple double click sees the required adjustment made to the value at each position in the fuel table. I was doing each cell one at a time as I didn't want to adjust the whole table in one go as there weren't enough samples in some locations for reliable outcomes. I ran through this a few times and the Lambda was looking reasonably steady. The main thing was that it wasn't going lean, which it had been. Although the engine seems to run sweet and the logs show a reasonable Lambda, the fuel map, when you change from a chart type display to graphic looks very peaky as there are values in a few locations that need further adjustment. Some may need to be adjusted without a logged Lambda as the engine is never operated with that particular combination of RPM and TPS. I really need to have a better fuel map as it is the basis for the fuelling when the turbo is fitted.
When boosted the fuel is dependent on the value from the fuel table and a multiplier which comes from another table. The multiplier values are determined by boost and RPM. With the turbo there will be areas of the main fuel map that are used which when unboosted might not be.
So many things to adjust. I'm going to run ECU controlled boost as well so something else to sort out, and I've cut the intake plenum so also need to machine a piece to go on the front to connect the turbo outlet.
I'm gonna need to talk sweetly to Rob & Cully about a bit more dyno time, after I fix the exhaust pipe that broke right at the flange. The other pipe has already been welded by someone else at some stage. Rob did mention that the bike was a bit rowdy so maybe a little bit of work there as well if the turbo gets delayed for some reason. I like the sound of it. For a 125cc twin it sounds reasonably serious. The 100cc(cough) turbo version will sound quite different with the turbo but the last one had a nice sound.

[pete376403]

If anyone knows of a small EFI fuel pump that is capable of pumping say 50hp worth of fuel I'd be interested in having a look.
Probably doesnt meet your requirements of "small" but for a turbo project I built years ago (speedway 1440 mini) I used a Triumph 2.5 PI pump. LOTS of pressure and volume. Most of the fuel it pumps went straight back to the tank via the boost modulated regulator

[speedpro]

I have sat looking over the fuel system and in particular my surge tank setup. The theory of it seems fine with the idea that an uninterrupted supply of fuel is important going to the pump. However, I have the return line also going to the surge tank and this return line seems to return fuel along with a reasonable stream of bubbles. These bubbles build up in the tank over a bit of time. On the dyno it may not be a problem as typically there is a fuel supply on a pole and the fuel line is directly down and into the surge tank. Fuel gets in easily and the bubbles are able to exit given the reasonably straight path up and out. With the setup on the bike the bubbles aren't able to exit so easily.

There seems to be a few options. The first one I thought of is to fit a nipple to top of the surge tank which attaches to the top of the main fuel tank via a tube. This would allow the bubbles to exit out to the main tank. The 2nd thought was to have the fuel return line go to the main fuel tank. There would still be a possibility of bubbles getting into the surge tank but only through the fuel line from the main tank which wouldn't normally be too much of an issue except that any fuel the pump pulls out of the surge tank has to be replaced by fuel from the main tank in a continuous cycle. If the pickup in the main tank is exposed for any reason it will simply suck air and fill the surge tank. whether that is actually a problem or not I don't know.

I've never seen an actual in-tank EFI pump setup but that is the obvious 3rd option.

I'm leaning toward the 1st option but if anyone has an idea . . . . .

[Vannik]

Returning fuel is often aerated and warm, in a well designed FI tank the return flow is on the bottom of the tank to stop the fuel from forming a jet into the fuel which can add more air. The return is also separated from the suction point by one or more baffle plates. On an FI system the fuel is used to cool the injectors and then there is often a cooler added to the return line. Fuel temperature is quite critical as both FI and carburetors are volume control instruments while AFR is a mass ratio. Controlling the temperature and thus the density of the fuel is critical.

[Flettner]

I have sat looking over the fuel system and in particular my surge tank setup. The theory of it seems fine with the idea that an uninterrupted supply of fuel is important going to the pump. However, I have the return line also going to the surge tank and this return line seems to return fuel along with a reasonable stream of bubbles. These bubbles build up in the tank over a bit of time. On the dyno it may not be a problem as typically there is a fuel supply on a pole and the fuel line is directly down and into the surge tank. Fuel gets in easily and the bubbles are able to exit given the reasonably straight path up and out. With the setup on the bike the bubbles aren't able to exit so easily.

There seems to be a few options. The first one I thought of is to fit a nipple to top of the surge tank which attaches to the top of the main fuel tank via a tube. This would allow the bubbles to exit out to the main tank. The 2nd thought was to have the fuel return line go to the main fuel tank. There would still be a possibility of bubbles getting into the surge tank but only through the fuel line from the main tank which wouldn't normally be too much of an issue except that any fuel the pump pulls out of the surge tank has to be replaced by fuel from the main tank in a continuous cycle. If the pickup in the main tank is exposed for any reason it will simply suck air and fill the surge tank. whether that is actually a problem or not I don't know.

I've never seen an actual in-tank EFI pump setup but that is the obvious 3rd option.

I'm leaning toward the 1st option but if anyone has an idea . . . . .

With my autogyro's, I have a collector / surge / working tank, call it what you will. Originally it was of sealed design. Gas bubbles would build up after a short flight and cause the engine to lean out, or even stop. The fix in my case was to vent this tank. Fitting a clear line saw gas bubbles continuously rising out of this tank, no matter how long the engine ran. After this vent was fitted, no more in flight engine issues.

My 360 has an in tank pump, circuit return is well away from the pump intake, pointing down, near the bottom of the tank.

[pete376403]

Would this be any use? Controls the pump so a return is not required. May not meet your requirement of rising pressure with boost
https://www.madhu.com/content/Main/FuelPumpController

[speedpro]

Good feedback and suggestions, thanks. Adding a vent to the surge tank seems like a good idea and I'm part way through doing just that. Cooling the fuel or at least reducing the variation in temperature also seems like it's worth looking at. I don't feel like making another surge tank with baffles between the return line and the pump supply line. Another option could be to pipe the return line into the main fuel tank. Fuel sucked out of the surge tank would be replenished by the normal fuel line from the main tank and the return fuel could be fed into the main tank in any place. I actually have a bolt on fitting with two pipes out the bottom. On the inside of this fitting one outlet has an extension tube. This connection could be used for the return putting the bubbles in the returning fuel above the outlet to the surge tank, or I could simply fit another fitting to the tank and connect the return line to that. This would increase the mass of fuel absorbing the injector heat, rather than only the small amount of fuel in the surge tank, plus increase the area radiating any heat which also would not be behind the hot engine. I'd have to make sure that the fuel line from the main tank to the surge tank flowed more than the pump was sucking out or it would simply draw down the fuel level.

The bottom of the tank already has a layer of foam rubber. I wonder if that was to keep engine heat away from the fuel?

[speedpro]

I have been thinking about engines and rod length ratios and so on.

What I wonder about is if there is a better velocity profile for a piston when it comes to extracting the maximum power from the fuel/air combustion. Currently the piston velocity varies at a more or less sinusoidal rate. Would there be any benefit to having the piston move at a different velocity at various points around TDC and ignition. Could more power be extracted if the piston moved at a slower pace after ignition and accelerated at a slower rate or would faster be better?

I'm not asking how it would be achieved although I have been thinking about how it might be done. I am interested in the theory of extracting power from fuel and air as it combusts and how that would most efficiently be done using a piston whose speed could be altered from the current piston speed at the same RPM.

[F5 Dave]

Start by asking how much friction would be added to such a bottom end beyond the plain or roller bearing crank, and what happens to the heat, and what happens if it can't keep up.

[husaberg]

I have been thinking about engines and rod length ratios and so on.

What I wonder about is if there is a better velocity profile for a piston when it comes to extracting the maximum power from the fuel/air combustion. Currently the piston velocity varies at a more or less sinusoidal rate. Would there be any benefit to having the piston move at a different velocity at various points around TDC and ignition. Could more power be extracted if the piston moved at a slower pace after ignition and accelerated at a slower rate or would faster be better?

I'm not asking how it would be achieved although I have been thinking about how it might be done. I am interested in the theory of extracting power from fuel and air as it combusts and how that would most efficiently be done using a piston whose speed could be altered from the current piston speed at the same RPM.


Generally Formula 1 and motorcycle engines - have rod ratios of more than 2:1.
Honda know this but their street engines but for economy tend to have much shorter rod ratios this maybe to saver materials in engine parts and blocks.

With the dwell you gain in one area but lose in another.
Your FZr has two rod lengths used in the two main models the difference being made up not in the deck height but in the piston deck height
With the the pistons design as far as i know, the closer the ring is to the top the more power it makes.
but the more heat it is exposed to so in your case with a turbo will this extra heat rings be worth it?

[speedpro]

This is nothing to do with the FZR. Just a new thought.

[speedpro]

Been tidying up the exhaust system for my FZR. Once I get the fuel map where I want it this lot will go back on. There's still a new piece needs to be made for the intake plenum to connect to the turbo. I have a few plans for the intake and have cut the plenum inlet and mounted a flange. There is a longer term plan to remake the exhaust manifold and to relocate the turbo directly in front of cylinders 3 & 4. In the meantime I'll probably run this system and properly set the paint and then wrap the exhaust to trap the heat to aid with maintaining the gas volume between exhaust port and turbo. EDIT: the turbo tailpipe isn't tapered. It just looks that way in the photo. Plus I still have work to do on the tailpipe to plumb in the wastegate outlet.

[speedpro]

Done a bit more painting, this time it's the intake plenum. This afternoon I also made an alloy adapter that bolts on the plenum and connects the hose from the turbo. It took way longer than expected but there was a bit more to machining it than I thought. Thanks to Kevin at Motorcad for showing me. Just need holes for the mounting bolts and it'll be finished

[speedpro]

Bolted together. After a bit of tuning tomorrow it will be installed with the turbo and then things will start getting serious. 40hp would bring a smile to my face.

[F5 Dave]

That's for pussies. Turn the pressure up until it blows, then rebuild the other side.

And obviously try just a little bit more. Just a smidge.

[speedpro]

Had an enjoyable and successful afternoon at ESE with the FZR on the dyno. I was doing runs at various throttle settings and logging the AFR so adjustments could be made to the fuel map. I made up a "desired lambda" table and the ECU can do a comparison of "desired" and "actual" lambda and also calculate what adjustment is required to make them match at every TPS position and RPM point. You only have to hold the throttle position and let the motor rev through the region of the fuel map you are tuning.

It's not perfect but does work very well.

One reason I wanted to do this all again is that last time resulted in a peaky looking fuel map. What I expected was a progressive change in values. I was very careful today to concentrate on the locations that had peak values with lower values each side.

The outcome was a fuel map with a ridge of peak values at 7000rpm and another ridge of peak values at approx 14,000rpm and partly into 15,000rpm. It doesn't seem to be an error as I went over it more than once.

I suspect it might have something to do with peak power supposedly being at 14,000rpm in standard trim. If this is correct it does highlight the compromises made using carburetors which will be incapable of fuel delivery with the peaks and troughs.

The attached table has the peaks highlighted. In the graphical version of the table it is REALLY obvious.

[speedpro]

Here's a sample mixture map. The squares are highlighted in red-green depending on how far away from the desired value the actual logged value is. The light blue highlight cells are ones I have double clicked to update the fuel map.

[TZ350]

.
The maps are very interesting. I am looking forward to the dyno results with turbocharging.

[Grumph]

The outcome was a fuel map with a ridge of peak values at 7000rpm and another ridge of peak values at approx 14,000rpm and partly into 15,000rpm. It doesn't seem to be an error as I went over it more than once.

I suspect it might have something to do with peak power supposedly being at 14,000rpm in standard trim. If this is correct it does highlight the compromises made using carburetors which will be incapable of fuel delivery with the peaks and troughs.

The attached table has the peaks highlighted. In the graphical version of the table it is REALLY obvious.

Historically, Yamaha have got round the mixture peaks and troughs by tweaking the ignition advance curve. Too rich at one point and can't change it ? - Add advance. Lean - retard at that point.
The ignition curves for the five valvers show this up perfectly.

[speedpro]

Spent time dummying up the turbo install today. Getting the turbo back together with the bits lined up relative to each other and fitted back on the bike was a mission but I'm there now. The electric waterpump is going to need a new home, or I'll need to change a few things with the turbo compressor inlet and airfilter. There also a little boost control valve that is going to need a home. I forgot how tight a fit the turbo is in the bike and to the engine. Maybe it's a good time to relocate it to the front of the engine but that brings it's own set of problems.

My wife asked why I do it. She doesn't understand these things.

[F5 Dave]

Then again she asked me when we were staying like almost 20 years ago why young guys like me did racing as you and Jimmy were a lot older.

I mean, she had a point.

[speedpro]

. . . . you and Jimmy were a lot older.

and faster

[speedpro]

It's a bit "busy" on the left now. I'm going to angle the airfilter up and back a bit to clear the electric water pump, for the moment. My plan is now to make a new as short as possible exhaust manifold and mount the turbo right in front of the exhaust ports. A lot more heat and energy will be retained in the exhaust gas that way.
It will also tidy up the plumbing a whole lot. I'll get it going first with all the stuff I already have.

[speedpro]

Sometimes I'm not sure how to make something and start off figuring it out with a basic drawing. This is for the new turbo exhaust manifold. I'd found what size u-bend that was the closest to what I needed and of course I had the size above and size below what I wanted. I was getting my mate Kev to weld the air filter mounting flange and he mentioned that the place over the road had mandrel bends. I popped over to check it out but the guys were saying no they didn't, but . . . . . they had these other little pipes in black steel. They were OK but a bit too solid. However these little SS pieces are basically what I drew so were a bit too hard not to buy. I was considering stainless steel and these kicked that idea over the line.
Nice little winner to end a cold wet miserable day.

[speedpro]

Had a productive couple of hours spinning up a couple of exhaust spigots for the new turbo manifold. I still need to sort out a few things like whether to weld the mounting flanges to the pipes or not. I'm currently leaning toward welding as it will provide another layer of support. I finally got around to removing the turbo from the bike to measure the inlet. It's way smaller than the gasket so lucky I did.

[speedpro]

How to assemble the pipes to the bosses and flanges.

I'm thinking the idea is to weld the pipe direct to the boss. I'll need to make a simple jig to line the pipe up on the boss but that's easy.
Then the flange can be slid down, the pipe oriented at the correct angle to meet up with the other pipe, and the flange then welded to the pipe. I might also weld the flange to the boss on the other side. This should make a reasonably secure structure once welded to the other pipe.
Where the pipes come together and the turbo is mounted, the 2 pipes with an ID of 28mm will be machined with flats where they join together. Slightly more than 1/2 the diameter will need to be removed and then once welded together the end will have to be made round and hopefully have an ID matching the turbine inlet of about 24mm. A slight adjustment could be made using the flange. I don't think it's critical as the turbine housing inlet is as-cast and not particularly round. Something close would be good though.

I 3D printed a flange so I can get a better idea of how it goes together

[speedpro]

A bit more progress on the turbo exhaust manifold. In the end I didn't need a guide to centre the pipe on the boss. Instead I made the boss as I had drawn it with a recess that the pipe fits into. I dropped over to Kev's place last night to chat about how this was going to be assembled. In the end Kev machined the taper in the boss, 26mm-28mm, and then the recess. After tacking each pipe to a boss we then jigged it up on the bench and scribed the cut lines. If I had cut it in the mill instead of with a cutoff disc in the grinder it would have been spot on.

The good thing is that cutting the pipe so that the 2 halves fit together leaves the exit a bit small so I'll have to cut it back till the size is correct. Giving it a quick eyeball the turbo was going to be a bit close to the front wheel but there is a couple of things I can do if required.

[speedpro]

Got a bit more done over the weekend. Kev gave me a piece of aluminium. In the lathe I faced off the top and bottom so they were flat and parallel and spun the exterior to clean it up so I could get a good reference off it. Drilled a 10mm hole through the middle to clamp it on the mill. It was then clamped down on the mill, clocked up to locate the centre and then offset in the X axis to the distance for the flange bolts which I then spotted. Took it over to the drill press and drilled and tapped the mounting holes. Once that was done I mounted the first flange on the alloy and mounted it in the lathe. I drilled the centre hole using a big drill and then bored it out to the desired size. I actually went up .25mm in size to get it over the pipes. The 2nd flange was simply a repeat. The good thing is that now I have the alloy boss I can easily make more flanges with good accuracy. The pipes need a bit more taken off the ends where the turbo mounts. It looks like it's OK but until there is a slight gap it's hard to tell if the pipes are under any stress. Pretty happy with how it's coming along.

I have decided to get my own machine tools. A good friend gave me his drill mill which I have used previously a very long time ago. I'm still looking for a lathe. The mill is 3phase and I've decided to go with a rotary phase converter so a 3phase lathe is fine as well. It turns out that I could get a 240v 32amp supply to the garage. I very much doubt I'll need anything like that, but it's nice to know.

[speedpro]

Update. Change of plan with the rotary converter. The motor on the drillmill is only 1hp although it is 3ph, so I'm going with a simple(cheap) 1ph to 3ph VFD. I'm hoping I'll be able to retain the 2 speed on the mill as it simply switches the motor from 2-4 pole. The VFD will be used to start/stop the mill.

The Argon Arc lighting system I bought has a small 15A plug. Basically a standard 240V 10A connector but with a larger earth pin. With the wiring kitset there is an industrial style 15A outlet and plug. I'll definitely install the outlet but may not bother using it just at the moment. A smaller residential style 15A outlet will be sufficient I think as that's what the welder has fitted although it does say that the maximum input current is 22A

I have a large 240V 32A switch and socket which i thought might be needed for the mill but it seems it's only purpose may be in the future "if" we ever go with an electric vehicle.

The other toy is due mid-month so it's all a bit exciting.

Reassembling the drillmill is looking like a bit of a challenge. The problem is that it's a bit hefty. It got moved with a forklift and a crane was used while we dismantled it and loaded it on my trailer.

[Grumph]

Hire or borrow an engine hoist. They're on wheels and can go up quite high.

[speedpro]

An engine hoist does look to be the answer.

[speedpro]

Assembled and more or less where it will probably end up. There's a bit to do before it can be used, like getting power to it, and I need to check the setup.

[F5 Dave]

Great stuff. I convinced work we needed one over 20 years ago that looked very similar in size and construction. If they ever make me redundant I'll be angling for it.

[speedpro]

I've been a bit lazy. Various bits have arrived from China about 2-3 weeks after ordering which I am pretty happy with. I now have a collection of ER32 collets and associated collet chuck, and a boring head which supposedly goes to 2"/52mm. I think if the boring bars are put in the end rather than sticking out the bottom it might just be able to bore a cylinder the size of Gary's bucket. I also ordered a collection of tool steel cutters. Probably not so great for cutting steel but just fine for aluminium. I got a VFD/VSD as well to run the mill. That will need a bit of wiring and I want a "kill" button somewhere handy as well but the electrician wiring the rest of the garage can sort that out.

I had a plan to visit Edgecombe on Friday but the weather was crap so I didn't bother driving down. Cricket and I still went to Hamilton to visit Boyd Motorcycles to collect a new slick. Had a quick chat with Aaron Gullery who works in the parts department. He's an ex bucket racer from a few years ago and also ran an RS125 for a short time. I haven't seen him for a very long time. Aaron is a real decent sort as was his Dad, Charlie(RIP).

I have the MB powered bucket ready on the trailer for HD tomorrow. Cricket is riding it. I'm really looking forward to it. Just a shame that the FZR twin is not really ready for a race day. That was one reason I was keen to go to Edgecombe, to get a bit of low pressure time running the bike and to gather data for tuning.

I also had a thought about going to Edgecombe on Monday. You can do that when you are old and retired. What I forgot was that a new toy is being delivered Monday morning which I need to be here to organize. There's going to be no excuses for not sorting out my rolling road and anything else that needs to be fabricated.

[F5 Dave]

Charlie was super keen. He seemed to enjoy his life so I hope that continued.

[speedpro]

New toy has been installed for a while and is now covered in swarf. Built a DTI holder which mate Kev had already roughed out and finished it using his mill. Very useful for locating TDC. The first use was to check where the timing marks were on the original YZ ignition. I suspect they should have been lined up at TDC but were actually at .92mm BTDC. Timing had been determined on the dyno years ago on another MB and I had simply lined the marks up that I had chiseled into the stator and adaptor. After that it was sussing out how to cut a taper in an early RM80 ignition to fit the MB crankshaft. Initially it seemed the taper was a 10:1 as measured in a couple of rotors that at various times have been fitted to an MB crank. When carefully checked I found that they weren't actually all that good a fit so I made a test piece and adjusted the cut angle until it was a good fit on the crank. The first real cut I did on a RM125 rotor which is essentially the same. That worked OK so I did the RM80 rotor which turned out spot on at the first attempt. I think the taper may be 7 degrees. If I get bored I might check where the compound slide is set using the DRO and determining the X & Y coordinates with various slide positions then a bit of trig to calculate the angle. The good news is that with the rotor lightly bolted in place and holding the stator in place the bike has a spark again. It lost spark at the end of P2 at HD at the last meeting. Very frustrating

[speedpro]

The MB engine bike is going back together and now runs. I spun the motor with the plug removed and marked where the ignition fires. I then moved that firing point to about 1.7mm BTDC. It fired straight up on the driveway but the throttle response isn't as instant as before so the timing must be off which is no surprise. I stripped the plastic cover off the ignition wires where it had become hard. It was surprising how much dirt was inside. I'm going to fit braided sleeve over it later.

[speedpro]

Cricket has bought and donated a late model RS125 style seat for the bike. I think he was embarrassed by the old seat. It actually goes reasonably well with the fat standard FZR tank.

I've also made a "race pattern" gear lever arrangement for him. I need to shorten the rod about 5mm to allow a better range of adjustment. The bit clamped on the motor gear selector shaft probably needs to come back one spline now that the rod is at a different angle. Just to maintain 90degrees between the rod, rod mount, and shaft.

I'm just in the process of making an aluminium seat support bracket which so far is going OK. The front attachment will require a bit of thought so it isn't too horrible. The cylindrical pieces will be welded to the ends of the box section. the cylindrical bits are threaded for the mounting bolts. Not sure yet but I'll probably spin up some washers which will spread the load around the mounting points.

Helping along all this fabrication is the VFD which I have fitted into a tupperware style plastic container and installed on the mill which has a 3phaze motor. So far it's working great even without any ventilation holes. No swarf is getting to this vfd.

This bike turned into #81 at the last meeting so I might start another thread. #6 is ready for a bit of tuning after having the turbo reinstalled and changes made to the configuration in the Link ECU.

[speedpro]

A couple of sessions just running the engine through the rev range at various throttle settings has been quite successful. Installing the turbo completely changed the fuel requirements. I wanted to tune the engine off-boost but with much more than 50% throttle and 10,000rpm it was making boost and so the 4D fuel table came into play and was compensating for boost. I haven't installed the boost controller so it's simply the wastegate on the turbo. So far it's only making about .4BAR or about 6lbs boost. It seems quite happy just using the main fuel table for fuel calculations at this boost so I have set values in the 4D table to very small values. I need to revisit the main map values after the changes but I want to do that anyway as although it's looking pretty good the map is still a bit bumpy. Once I start tuning with more boost I will use the 4D table alone to make adjustments.
It's quite nice the way the engine picks up revs as the boost comes on. I bumped into the 18K rev limit a few times with no effort at all. It would already be nice to ride. The engine is responsive to throttle movement at any revs.

[speedpro]

I made a comment on FB that after Tokoroa I gave the MB powered bike a clean and did a few minor repairs and it was good to go again. Then I had a look at the gearbox oil, followed by completely dismantling the engine to replace a seal. I replaced the crank main bearings as well and trued up the crank again, just to make it better. It's back together now and started in one of two steps down the drive and seems as responsive as previously.
I quite like the new seat unit that Cricket bought. It matches the tank reasonably well.

[F5 Dave]

Good to see old MBs still up and running. My old one has a pretty coat of red Mal put on it and hes made a better job of the engine mounts than I did as it used to break bolts.

[speedpro]

Back to the turbo FZR. Boost control solenoid now fitted. Now the fun begins juggling the fuel map values off-boost with the 4D fuel map compensation for on-boost. I had the fuel map reasonably good without the turbo. Adding the turbo changed the fuel requirements much more than I expected, even without boost. The fuel map is pretty lumpy but a lot of the values have been determined by either dyno runs or running it around Edgecumbe. The engine seems to have fuel demand peaks through 7,000rpm and again at 14,000rpm at most of the throttle range. Never mind, I'll get there.

The question is, will this be the last gizmo added? I'm actually starting to feel like the bike is nearly finished as it's getting to where I envisaged it. Making the engine I originally envisaged using FZR bits isn't going to happen. Originally I thought of a v-twin driving a CVT, fuel injected, etc.

[F5 Dave]

So remind me. With the turbo the plan is then to short stroke it back to 100?

V-Twin huh? I'd held an RG50 crankcase up and pondered making a 100 V. Couple of AM6 barrels 14,000. 35hp easy.

But can't be arsed now.

[husaberg]

Back to the turbo FZR. Boost control solenoid now fitted. Now the fun begins juggling the fuel map values off-boost with the 4D fuel map compensation for on-boost. I had the fuel map reasonably good without the turbo. Adding the turbo changed the fuel requirements much more than I expected, even without boost. The fuel map is pretty lumpy but a lot of the values have been determined by either dyno runs or running it around Edgecumbe. The engine seems to have fuel demand peaks through 7,000rpm and again at 14,000rpm at most of the throttle range. Never mind, I'll get there.

The question is, will this be the last gizmo added? I'm actually starting to feel like the bike is nearly finished as it's getting to where I envisaged it. Making the engine I originally envisaged using FZR bits isn't going to happen. Originally I thought of a v-twin driving a CVT, fuel injected, etc.

have you seen the prodrive rocket antilag pictures and videos.
i am pretty sure that's what keith Duckworth was proposing only on a less grand scale.

this is likely one of the better explanations

https://www.youtube.com/watch?v=qpJYQ9Fydso

https://www.youtube.com/watch?v=KRx1mcxZDhY
here is one i missed
https://www.youtube.com/watch?v=qzE5hGIRnoQ
https://www.youtube.com/watch?v=f9ghF1A-1UI
https://www.youtube.com/watch?v=QDaKRrPHw80

[speedpro]

The turbo construction is more or less complete. I want to work on the tuning as I mentioned and at some point get a power figure. Funnily enough there is a specific class for small blown bikes at speed events so it would be interesting to give that a shot eventually. In the meantime I'm going to start work making an adaptor for the end of the shaft on my rolling road so I can use a kart starter to spin the roller. It'll still be a 2 person job to start the bike, although my throttle stop thingy would do if I get stuck. With that I'll be able to tune the mixture using the WB Lambda. I'll try to get the off-boost as good as I can and then go to pulling boost and see if I can control the boost and use the 4D fuel table to control fuel mixture on boost. Kevin has already provided a chunk of alloy for the adaptor which I'll turn in my lathe tomorrow and hopefully get on his mill with the rotary table to cut the hex for the started to engage with on Sunday.

I was tossing up what was going to be the next project and have decided to get Greg's bike going. First up it's getting a nice green coat of paint. It doesn't look like there is actually all that much that needs to be done to make it rideable. Greg has done some really nice work constructing this bike. Lots of clever little touches. It certainly puts my effort to shame. Apart from the paint I'm seriously considering a pair of Maikuni YD30 carbs although I have a pair of carbs that Greg provided and also a pair of standard FZR250 carbs I used on mine when I first got it going. The YD30s would certainly look the part but we'll see.

[speedpro]

The 3 FZR chassis I have all have completely different suspension. The MB powered ex-ESE chassis is the firmest. I haven't ridden it but Cricket had no complaints. Those forks have spacers and washers installed and I don't know what else. The shock does have a damping adjuster which I haven't played with and the dogbones might not be stock. My FZR turbo is in the middle. I messed with the forks quite a bit. They have emulators fitted which I have firmed up a bit. The rear end is completely stock as far as I can tell. Originally I set sag both ends as per various instructions. Greg's bike is the softest. I haven't looked at the forks but the rear shock has a piggyback reservoir and 2 damping adjusters.

I need to get someone who has an idea what they are doing to have a look and make suggestions.

[speedpro]

A possibility for carbs - https://www.aliexpress.com/item/32919020215.html?spm=a2g0o.detail.1000014.8.56fe48 61WJDgup&gps-id=pcDetailBottomMoreOtherSeller&scm=1007.40050.281175.0&scm_id=1007.40050.281175.0&scm-url=1007.40050.281175.0&pvid=cef2e20b-5c43-499d-bb17-1160e4324c3a&_t=gps-id:pcDetailBottomMoreOtherSeller,scm-url:1007.40050.281175.0,pvid:cef2e20b-5c43-499d-bb17-1160e4324c3a,tpp_buckets:668%232846%238110%231995&pdp_npi=3%40dis%21NZD%2197.71%2165.47%21%21%21%21% 21%402101c5b116814704714893123ee9b1%2165974587428% 21rec%21NZ%212359987129

[Grumph]

The suspension on the one from me is set for a lighter 2T engine, a small girl rider and kart tracks. Could almost certainly do with firming up as it's unlikely you'd find another rider as light as the last. Rob may remember setting it up and where the shock came from.

How do another EFI setup and a set of carbs compare on price ? I lost my money attempting to buy a set of 28mm downdraft FCR's. From an apparently reputable dealer in Holland. Bastard. Not cheap either.

Green........the old man would never paint anything green as he swore it was unlucky.....

[husaberg]

https://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1129689781#post1129689781

https://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1129690207&highlight=shock#post1129690207

[pete376403]

The suspension on the one from me is set for a lighter 2T engine, a small girl rider and kart tracks. Could almost certainly do with firming up as it's unlikely you'd find another rider as light as the last. Rob may remember setting it up and where the shock came from.

How do another EFI setup and a set of carbs compare on price ? I lost my money attempting to buy a set of 28mm downdraft FCR's. From an apparently reputable dealer in Holland. Bastard. Not cheap either.

EFI? Speeduino, with TunerStudio on laptop. There will be plenty of donor bikes in wreckers for fuel pump and throttle body, if I read your post correctly you already have WB sensor. Plus with Speeduino you also get fully mappable ignition as well as fuel. WMtronics sell a self assembly kit (NO2C) that is not too difficult if you can follow instructions

[Grumph]

At one point Mike was talking about simply swapping the EFI over from the turbo'd bike. He'd already got it rideable unblown and responding nicely.
So my question was effectively how much to duplicate the existing setup Vs cost of carbs.

This one is bored to 150cc and has an improved inlet cam so was intended to be run unblown. He's got it cos circumstances forced my downsizing.

Doesn't stop me commenting though - sorry Mike.

[speedpro]

EFI requires things that I can't be bothered making again. Carbs you bolt in, and after a bit of fiddling they're all good. The bike has a FZR250 2KR model ignition module and decent looking coils. I'm close to having done what I want with EFI and turbo on my bike and don't feel the need to do it again. I'd just like to get Greg's bike going. Carbs is the easy solution.

[Grumph]

I think I told you I was going to put a smaller tank onto the underside of that steel tank cover. The carbs on it now don't like pump feed and if it's going to be on kart tracks the alloy tank is too big. I was aiming it for BoB and other big track races down here.

[speedpro]

No sweat. If I try those carbs I'll make a small header tank the pump can feed, from which the fuel can fall into the carbs, and any excess simply recirculate back to the main tank. I had a similar system on my MB sidecar.

[speedpro]

Made a small endcap to fit the end of the shaft of the rolling road I built. The idea is to use a kart starter to turn the roller. Hopefully the alloy will be up to it. The end of the shaft already has a couple of threaded holes in it. Surprisingly and unfortunately the 2 holes aren't the same distance from the centre so I can't simply make 2 holes in this cap on a pitch circle. I'm makingt little pointy bits that can be screwed into the holes and which I will then tap the cap onto to leave indents marking the centres of the holes. Bit of a pain.

[speedpro]

Could there be a 4T single begging to be made using one cylinder from this head. Standard piston size is about 75mm I think so a bit small for Gary but big enough for most of the fast singles.

[Grumph]

The late Suzukis are lift limited by the small OD of the cam follower buckets. I've had engines with Yosh cams and the factory kit cams through the workshop.
The Yosh cams are as big as you can go with conventional cam profiles. The kit cams have effectively an extra "finger" on the tip of the lobes to reach down into the follower bores for an extra .020in of lift.
Pretty sure someone will have the Yosh profiles copied locally. I took the precaution of getting the kit ones digitally copied while I had them here.
The guy who copied them said he didn't know how he'd grind them as the transition from main lobe to finger is a concave curve.
Either CNC or a very small grinding wheel needed.

I believe the reproduction Patons being built for classic racing use GSXR1000 parts and the head is pretty much a copy too. 500cc twins.

[speedpro]

Seen in the museum at Mt Panorama, Bathurst. Note the extra fins welded on. This was done some time in 1995 or so. Some may remember from bucket racing from about 1985 or so, a Honda 125 ridden by Tonto and possibly others, which had fin extensions welded on. In the bucket case there was an air scoop that directed air across the rear of the cylinder as well. As usual, buckets are well ahead of other motorsports.

[Grumph]

Pretty sure Ballard was doing it earlier than 1995. When I was at Budget in ChCh a local MX guy was pushing for us to become agents for Ballard. That was pre 1989. The big finned barrels and heads were to come from oz and I was to assemble the kitted motors.
Neither Kirby nor i saw any great profit in it so it didn't happen.

[husaberg]

Pretty sure Ballard was doing it earlier than 1995. When I was at Budget in ChCh a local MX guy was pushing for us to become agents for Ballard. That was pre 1989. The big finned barrels and heads were to come from oz and I was to assemble the kitted motors.
Neither Kirby nor i saw any great profit in it so it didn't happen.

They as far as i know were doing them in the states 89ish also for the desert racing and for flat track.
the big xrs as factory never had the oil coolers the 250s did but they used the frame as an oil cooler.

[speedpro]

The moment of truth approaches.

I'm penciled in for Saturday to get the bike on a dyno to tune the Link ECU. The very helpful owner has already sent me a couple of different setups, 1 of which I've spent a bit of time on my rolling road making adjustments. The trick is to get the base fuel map correct and the ECU takes care of fuel calculation in areas not covered by the base map, such as on boost. I ran it with the wastegate open so it was not making boost except a very small amount at 100% throttle and with quite a few revs. At 12,000rpm it was managing 105Kpa and really wanting to get going. I needed to brake it a lot more once it started winding up. I think the dyno operator is pretty much onto it. His provided fuel map was a bit rich but only a bit. I took a bit of fuel out while I was testing. No power measurement was possible I was just going off the Lambda. His timing map seemed to work pretty well but I expect it's going to need a bit of timing removed off boost in the higher rpm ranges. On boost the timing is already conservative so we'll test and see.

It feels like it's going to be a little monster. Either that or I'll bring it home in plastic bins

[speedpro]

I've been struggling to get it starting nicely. Using the kart starter I can turn it over at 2000rpm and I can see the injector pulsewidth is not where it should be for a cold start. I know from the past that I should see a 4-5mS pulsewidth and it is only the normal idle pulsewidth of a bit less than 2mS. It does climb up if I keep spinning it. Initially I set all the cold start tables to "0" and then doubled the base fuel map values in the area around where it starts. Voila. It fired up instantly which proved that the issue was fuelling. There seems to be a delay before the enrichment kicks in. Possibly it's the post-crank which I thought it wasn't even using.

[TZ350]

I've been struggling to get it starting nicely. Using the kart starter I can turn it over at 2000rpm and I can see the injector pulsewidth is not where it should be for a cold start. I know from the past that I should see a 4-5mS pulsewidth and it is only the normal idle pulsewidth of a bit less than 2mS. It does climb up if I keep spinning it. Initially I set all the cold start tables to "0" and then doubled the base fuel map values in the area around where it starts. Voila. It fired up instantly which proved that the issue was fuelling. There seems to be a delay before the enrichment kicks in. Possibly it's the post-crank which I thought it wasn't even using.

At 2,000 rpm, is it spinning faster than the starting cranking speed the ECU is expecting for a cold start? The ECU could be thinking it has already started and is running fine. There should be a setting somewhere that defines at what rpm cranking settings are dropped.

[speedpro]

Anything over 400rpm, yes - "400", is considered "post-cranking" speed. I don't think it's configurable. Pulling on the back wheel to spin the motor can see the engine hitting 3-3,500rpm, same with push starting. It could be that the extra speed sees the ECU switch out of the post-cranking zone into post-start enrichment after which it goes to warmup enrichment. Post-start enrichment decreases on a timer until it reaches the value in warmup enrichment when it swaps over. Warmup enrichment decreases as the engine warms up. It works sweet but at the moment there is an issue with enrichment from the moment the crank turns. It did seem to go direct to post-start enrichment previously. Hopefully it will be sorted out tomorrow on the dyno when it's being tuned properly.

Looking forward to tomorrow and seeing what it can do. Something like the power of a stock FZR250 would be cool.

Loaded ready for a 6AM departure.

[speedpro]

Tuning went VERY well apart from being cold and miserable most of the time. Kris really knows his stuff and is a great guy, very happy to help, and not judgy that it's "only" a bucket. His eddy current dyno is a car dyno and the bike was only spinning the front rollers. His software assumes the rear rollers are also being spun and calculates the power produced by including the inertia of both front and rear rollers. The end result is a high reading. I think it's good even subtracting an amount to compensate but I'll do a test run on the ESE dyno to get an accurate figure before making any claims. The thing is that there is more to go. Tuning is still conservative, only about 11psi boost, fuel is rich, timing is a couple of degrees less than we know it likes, and if the boost goes crazy timing is pulled out and fuel is dumped in to kill it. There's also a fuel cut programmed if it goes really crazy.

HD National circuit next weekend is going to require stock FZR gearing. I've never been around that circuit so it's hard to calculate. If anyone with a fast bucket could reply with the power and speed on the track that would be helpful.

[speedpro]

I have fitted a Gary Cunningham pre-worn rear tyre. No chicken strips on this tyre. I will of course be wearing out the middle bit that Gary has barely scrubbed in. I've also fitted original FZR250 gearing and hopefully will collect the new chain from the Restorace shop tomorrow. I've been going over the bike checking that it's OK and won't have problems at scrutineering. Turned out the back brake didn't work and nothing I did made any difference. It's almost like the hose is blocked. In the end I swapped the brake over from the MB powered FZR. One other thing I looked at was the rising rate of the fuel pressure regulator. It isn't 1:1 which it really needs to be so I'm on the hunt for a new one. Looks like good ones go for about $300, ouch! If at some point I make the decision to lean on the tune a bit, what I don't want is the fuel pressure to drop. On that topic, I was looking at the logs from the runs on the dyno. The current fuel pressure regulator does reduce the fuel pressure slightly at idle(3,000rpm) and then increases it as the throttle is opened and as manifold pressure increases. Despite this the engine is a bit rich at idle even with an injector pulsewidth below the minimum recommended. Then at about 18,000rpm and .8BAR boost the injector duty cycle hit 89% in at least one moment. Another good reason to get the fuel pressure increasing properly. Otherwise the duty cycle might end up being the limiting factor.

I'm still hopeful of getting on the ESE dyno before Sunday just to see what power it actually makes.

[speedpro]

This is the main fuel map in graphical mode. That chasm is at 9,000rpm. The map has been smoothed out a bit as AFR is not too critical for power and the engine is rich, running at about 11:1AFR or Lambda .8ish. Fuel will be aiding cooling with this much going in.

[husaberg]

I have fitted a Gary Cunningham pre-worn rear tyre. No chicken strips on this tyre. I will of course be wearing out the middle bit that Gary has barely scrubbed in. I've also fitted original FZR250 gearing and hopefully will collect the new chain from the Restorace shop tomorrow. I've been going over the bike checking that it's OK and won't have problems at scrutineering. Turned out the back brake didn't work and nothing I did made any difference. It's almost like the hose is blocked. In the end I swapped the brake over from the MB powered FZR. One other thing I looked at was the rising rate of the fuel pressure regulator. It isn't 1:1 which it really needs to be so I'm on the hunt for a new one. Looks like good ones go for about $300, ouch! If at some point I make the decision to lean on the tune a bit, what I don't want is the fuel pressure to drop. On that topic, I was looking at the logs from the runs on the dyno. The current fuel pressure regulator does reduce the fuel pressure slightly at idle(3,000rpm) and then increases it as the throttle is opened and as manifold pressure increases. Despite this the engine is a bit rich at idle even with an injector pulsewidth below the minimum recommended. Then at about 18,000rpm and .8BAR boost the injector duty cycle hit 89% in at least one moment. Another good reason to get the fuel pressure increasing properly. Otherwise the duty cycle might end up being the limiting factor.

I'm still hopeful of getting on the ESE dyno before Sunday just to see what power it actually makes.
turbogemini sell them..but with EFi why do you need a rising rate? of 1:1 i thought that was for carby engines
http://turbogemini.com/Blow%20Through%20FPR.htm
this one appears a bit flashererererer
https://turbobits.co.nz/products/rising-rate-fuel-pressure-regulator-full-kit-fpr
oh the answer is in your post :)

[speedpro]

The ignition map is far more normal. Advance off boost is about 36-37° and once it starts making boost is backed off to about 20-25° at 180kPa manifold pressure which is as far as we've gone so far. The map reduces timing a lot more past there but no testing has been done over 180kPa. Not deliberately anyway.

[speedpro]

The new chain is installed. I tipped a bit of fuel in and fired it up to see if it was cold starting any easier. It isn't. I warmed it up pretty good and it wasn't quite idling if I released the throttle. On the dyno it liked about .5% throttle to idle happily. Then I fitted the $mega iridium spark plugs and fired it up again. Warm it fires up instantly and despite cooling down a bit while I changed the plugs it still idled happily without any throttle. The only change was the plugs so it looks like they may be a worthwhile investment.

I was thinking about how good a garage would be at HD. If anyone has hired a garage I would be happy to pay the usual fee and share. You'd have to be OK with a bucket in your garage and all the attention that buckets get