#6

[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


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/3291...Z%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/s...post1129689781

https://www.kiwibiker.co.nz/forums/s...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