#6

[crazy man]

l know years ago a bucket sidecar had a supercharger on it but it ran another motor on it which is within the rulzs

[TZ350]

l know years ago a bucket sidecar had a supercharger on it but it ran another motor on it which is within the rulzs

Right on .... I had been looking at that too.... driving the supercharger with a donkey motor. Something from a weed eater might do the trick.

[speedpro]

Had to pull a cover off to check an oil leak so took a few pictures. You can see where the head has been sliced off through the tappet bores and ports. It was cut here so cam lobes could be ground down for the seals to run on as I wanted to be able to mount cam speed sensors for an ECU. The plate is mounted using a couple of 8mm cap screws into alloy of the head plus two 6mm screws into the cam bearing caps at the top. The seals fit over the cam and are then held pressed into the recesses in the end plate by the round caps. I didn't try and make the plate recesses exactly concentric with the cam centres as I figured I couldn't get it good enough for the seals to work properly. The seal to the end plate is between the plate and the end of the seals rather than their circumference.

I ran it again this afternoon after a few changes. You can see it in the video. After this I checked the oil and it was a lovely milky white slime. I thought there was also gas blowing through the water as it circulated. Obviously the head is going to have to come off as my homemade gasket isn't doing the job.

All the maching was done on a crappy old lathe I used to own and a simple drill press. Any grinding was done using my electric high speed grinder mounted on the tool post in a bracket I made, and taking really small cuts. There's probably some reason for not doing that but the end result was pretty good. I had covers over the bed.

http://www.youtube.com/watch?v=KGlP3oIBhuc

[F5 Dave]

Turbo l think is the way to go. my mate turboed a near stock rz 350 and made 150 rear hp but before he did that he super charged it and found it a wast of time. (l did not want to put this to put glen of cause you never know) ...he thinks the small motors suck way to much hp to make it work right . but the turbo he used was a verable vane one which at high rpm they fall over and let the exhaust work better. but over 2k of turbo

a hundred and fifty?!?? a hundred and fifty is 3x the stock. I didn't think 2 stroke turbos could be that efficient or stay together at that sort of level?

[crazy man]

a hundred and fifty?!?? a hundred and fifty is 3x the stock. I didn't think 2 stroke turbos could be that efficient or stay together at that sort of level?

had expashion chambers and fuel injected . he copyed it out of a book what somone else had done . he is a turbo , injection specialtist so know what he was doing

[Sketchy_Racer]

Had to pull a cover off to check an oil leak so took a few pictures. You can see where the head has been sliced off through the tappet bores and ports. It was cut here so cam lobes could be ground down for the seals to run on as I wanted to be able to mount cam speed sensors for an ECU. The plate is mounted using a couple of 8mm cap screws into alloy of the head plus two 6mm screws into the cam bearing caps at the top. The seals fit over the cam and are then held pressed into the recesses in the end plate by the round caps. I didn't try and make the plate recesses exactly concentric with the cam centres as I figured I couldn't get it good enough for the seals to work properly. The seal to the end plate is between the plate and the end of the seals rather than their circumference.

I ran it again this afternoon after a few changes. You can see it in the video. After this I checked the oil and it was a lovely milky white slime. I thought there was also gas blowing through the water as it circulated. Obviously the head is going to have to come off as my homemade gasket isn't doing the job.

All the maching was done on a crappy old lathe I used to own and a simple drill press. Any grinding was done using my electric high speed grinder mounted on the tool post in a bracket I made, and taking really small cuts. There's probably some reason for not doing that but the end result was pretty good. I had covers over the bed.

http://www.youtube.com/watch?v=KGlP3oIBhuc

Nice work in there, the only reason for not using a grinder on a lathe is just the grinding filings wear out the slideways after time but for small home lathes no problems. Mine often gets that sort of abuse.

What did you do with the crank, did you just pull the rods out or did you also cut that in half?

In the video it sounds like the engine feels free enough to run happily, just sounds like fueling issues to me.

[speedpro]

I hacksawed the crank between #2 big end journal and the inside main bearing then chucked it in the lathe with the fixed steady on the main bearing over one and turned down the remains till it was a nice round boss, just in case I want to mount something on it. I left the cases uncut as they are real thin and light so seemed no benefit seeing as the oil and water pump stick out past the end of the cases anyway. I have thought of sealing off the inside of the cases on that side and running a supercharger off that end of the crankshatf. Looking at it tonight however "if" I went the supercharger way I'd mount it out the front and run the ex pipes somewhere else.

[koba]

Nice.
I remember when my old GSXR250 dropped a LT wire to the coil I rode it around 10KM 'till I could get enough light at a petrol station to work out and fix the problem.
It wasn't all that slow, even working against the compression of two cylinders.

[speedpro]

The water in the oil is a problem, obviously. I've had a think about the source and it can only be from maybe two places. First is the oil pump to water pump connection though I can't fully remember how that all fits together. It will however be easy to check. The other is the head to cylinder joint next to the cam chain tunnel. Easy to get to but a pain to reassemble. I took the cam cover off tonight and snapped a few photos. They show just what a nice bit of gear these engines really are. You can also see how the end cam lobe is now a round shape for the oil seal plus the alloy boss jammed into the end of the cam and then machined down.

I also noted the cam timing. When I was building this engine I took the cams to Franklin Camshaft Services who as it turns out were very friendly. The guy mapped the cam profile and suggested cam timing for a forced induction engine using these cams. You can see in the photo the holes in the cam end bosses. These are supposed to be lined up with the gasket surface. These are not. The exhaust cam is retarded and the intake is advanced about the same amount with the effect of increased overlap. If I take it apart I'll have to check the lobe centres as I don't recall the numbers it's setup to. For some reason 105degree centres rings a bell. I'll find out tomorrow.

What I'll probably do is reassemble it with standard compression and cam timing and run it normally aspirated for testing purposes.

[Grumph]

The FZR heads like 103 inlet,104 ex lobes centers.

IMO roots blowers can work well - ours did - but appropriate sizing is necessary. Big run slowly is much more efficient than small run very fast....
Sketchy, don't be offended but IMO you went too small to start with and i have the suspicion that the new idea may also be too small for the rev range it will achieve...

A 300cc roots on this run at 1:1 should give around 12lb boost hot.

[speedpro]

I've decided to pressurise the cooling system and see where it runs out - obvious once I'd thought of it.

1:1 on the blower gives 12lbs boost? Seems a bit low given 300cc/rev into 125cc/2revs but I have no direct experience with sizes, drive ratios, and the results. I figure on only spinning the engine to about 15,000rpm which may be a bit fast for the supercharger but I really don't know what they are capable of, less than 15,000 I would have thought.

Hopefully I will be able to measure the centres tonight and compare to your suggestions. Will also measure centres as installed according to Yamaha.

[speedpro]

Talking of superchargers, my mates car had a 14/71 magnesium high helix on it. The engine was around 505cu in and would pull boost at a fast idle around 2,500rpm with no load. I doubted it when he told me but one day we were running it up with a new sheetmetal manifold and as he brought the revs up a small jet of methanol shot out of a pin hole in a weld. Even at 11:1 compression the supercharger was overdriven about 15% and boost was heaps. Gotta love methanol.

I ran my turbo bike up to 19lbs at the old Taupo track one day. It would wheelstand anywhere in any gear just by opening the throttle. All good until the bottom case cracked through #2 mainbearing support.

[Sketchy_Racer]

The FZR heads like 103 inlet,104 ex lobes centers.

IMO roots blowers can work well - ours did - but appropriate sizing is necessary. Big run slowly is much more efficient than small run very fast....
Sketchy, don't be offended but IMO you went too small to start with and i have the suspicion that the new idea may also be too small for the rev range it will achieve...

A 300cc roots on this run at 1:1 should give around 12lb boost hot.

I would agree now I have built and tested the blower, ironically I built it as I believed that the 300cc/rev output of the AMR300 was too much and outside the window of efficiency and weight, but turns out it would work almost perfect for our application.

The new design if anything looks like it will be too large in terms of mass air flow and the motor running at a 2.0 pressure ratio is right on the edge of the surge line. But, I have got smart since the last blower and the gearbox I am building will also accept a compressor wheel and compressor housing from another turbo quite a bit bigger if I need to go up in size without having to make the whole thing from scratch.

I've decided to pressurise the cooling system and see where it runs out - obvious once I'd thought of it.

1:1 on the blower gives 12lbs boost? Seems a bit low given 300cc/rev into 125cc/2revs but I have no direct experience with sizes, drive ratios, and the results. I figure on only spinning the engine to about 15,000rpm which may be a bit fast for the supercharger but I really don't know what they are capable of, less than 15,000 I would have thought.

Hopefully I will be able to measure the centers tonight and compare to your suggestions. Will also measure centres as installed according to Yamaha.

This is the formula that I used for calculating boost pressure with a roots blower.

Stolen from http://victorylibrary.com/supercharger/super-drive4.htm

R: drive ratio (supercharger RPM ÷ engine RPM).
C: engine displacement, either in cubic centimeters, liters ÷ 1,000, or cubic inches × 16.387.
B: boost, in pounds per square inch (psi).
A: Atmospheric pressure, in pounds per square inch (psi); 14.7 is approximately correct for sea
level and 70° F. Click for a Table of atmospheric pressure at higher elevations: ). Please
note that RAD is preferred to actual pressure when calculating the effects of air conditions on tuning.
V: supercharger volume in either in cubic centimeters, liters ÷ 1,000, or cubic inches × 16.387
per revolution; Roots volume is “displacement”, eccentric vane volume is “swept volume”.
O: Cam overlap; subtract 30 from the overlap in degrees, then multiply by 1% (.01). E.g. for 65°
overlap, O = 65 - 30 = 35, × 1% = .35.

R = C × (B + O + A) / V × 2 × A

[husaberg]

I would agree now I have built and tested the blower, ironically I built it as I believed that the 300cc/rev output of the AMR300 was too much and outside the window of efficiency and weight, but turns out it would work almost perfect for our application.

The new design if anything looks like it will be too large in terms of mass air flow and the motor running at a 2.0 pressure ratio is right on the edge of the surge line. But, I have got smart since the last blower and the gearbox I am building will also accept a compressor wheel and compressor housing from another turbo quite a bit bigger if I need to go up in size without having to make the whole thing from scratch.




This is the formula that I used for calculating boost pressure with a roots blower.

Stolen from http://victorylibrary.com/supercharger/super-drive4.htm

R: drive ratio (supercharger RPM ÷ engine RPM).
C: engine displacement, either in cubic centimeters, liters ÷ 1,000, or cubic inches × 16.387.
B: boost, in pounds per square inch (psi).
A: Atmospheric pressure, in pounds per square inch (psi); 14.7 is approximately correct for sea
level and 70° F. Click for a Table of atmospheric pressure at higher elevations: ). Please
note that RAD is preferred to actual pressure when calculating the effects of air conditions on tuning.
V: supercharger volume in either in cubic centimeters, liters ÷ 1,000, or cubic inches × 16.387
per revolution; Roots volume is “displacement”, eccentric vane volume is “swept volume”.
O: Cam overlap; subtract 30 from the overlap in degrees, then multiply by 1% (.01). E.g. for 65°
overlap, O = 65 - 30 = 35, × 1% = .35.

R = C × (B + O + A) / V × 2 × A

i came up with .5 engine speed 1.5 bar 0r 22psi ( assuming 100cc engine 300cc rootes blower) using less sophisticated formula?
which was within the limits of H2O avgas and intercooling....... just.

I've decided to pressurise the cooling system and see where it runs out - obvious once I'd thought of it.

1:1 on the blower gives 12lbs boost? Seems a bit low given 300cc/rev into 125cc/2revs but I have no direct experience with sizes, drive ratios, and the results. I figure on only spinning the engine to about 15,000rpm which may be a bit fast for the supercharger but I really don't know what they are capable of, less than 15,000 I would have thought.

Hopefully I will be able to measure the centres tonight and compare to your suggestions. Will also measure centres as installed according to Yamaha.

interesting to see how the valve timing clocks against the factory figures...... did you do yours at 1mm lift Mike?

I found the 3ln vs 2kr factory figure for timing and duration. ............seems the cam are probably the same only inlet is advanvcef 4 degress on the 3LN and the exhaust retarded 1 degree plus the carbs are 2mm bigger as well. interestingly the plugs are hotter?

[speedpro]

Finally got round to measuring the cams. Everything checked at least twice.

Exhaust is centred at 112deg BTDC, measured at 1mm lift it opens at 139deg ATDC and closes at 2deg BTDC
Intake is centred at 105.5deg ATDC, measured at 1mm lift it opens at 13deg BTDC and closes at 48deg ABDC.

The numbers seemed odd and not what I remembered. Anyway I had a look around inside and found the original readout sheet from Franklin Cam Services. It was dated 11:44AM Thu Jul 6 2000 to give you an idea how long this engine has taken to get into a bike. The suggestions were:

Exhaust centred at 110deg BTDC
Intake centred at 105deg ATDC.

Little bit out but obviously the intention was there. I'll adjust it tomorrow and measure the timing with the cams installed where they should be, if I can be bothered. Lift is 5.2mm ish. It's near impossible to get the DTI onto the buckets and I had to use a match screwed into my DTI to get down past the cam caps and the lobes.