(F.I.)^2 = Forced Induction×Fuel Injection

[Jusblowit]

New around here. My runner is an XS500, which shares surprisingly little with the 650... Which makes finding parts and advice a b***h. So a few years back I acquired a rolling basket case of a 650 with some grand aspirations. Didn't have much to spend on it at the time, so it sat as found for a while, and I started planning , buying parts, and doing whatever fabrication I could do myself. Some 5 years and the price of a nice brand new bike later... Finally seeing the light at the end of the tunnel, so wanted to share on here.

Currently the bike is apart for painting and motor rebuild with 750 rephase.

What we have here is a '78 650 with '87 FZR1000 front end, '91 FZR600 monocross swinger with the 1000 rear wheel modified to fit with an FT500 sprocket carrier which can hold a small enough sprocket to keep this from being a trials bike.

Non standard equipment: Ram air intake into 500cc/rev twin lobe blower driven off the PM generator, intercooler , and microsquirt powered Fuel injection and digital ignition. Why, you ask? Why not, I say.

Other details:
80s Suzuki gs650 tank
YZR replica tail (modified)
Rickman endurance fairing (shortened)
2000's R1 rear shock
Goldvalve cartridge emulators in the FZR forks up front
Hydraulic clutch from FZR
Remote oil filter+cooler
AN fittings throughout
Stainless 2-into-1 exhaust with Kerker can

What else...? Something will come to mind.
Let the snickering and "whyfors" begin...

 

[GLJ]

Pics or it's not real.

 

[Jusblowit]

Pics or it's not real.

Oh, it's very real...
*Pics added

 

[GLJ]

Looks interesting!

 

[59Tebo]

Holy Cripes! It'd be interesting to see dyno testing results from that! It may be too powerful for your own good!

 

[Jusblowit]

O

Holy Cripes! It'd be interesting to see dyno testing results from that! It may be too powerful for your own good!

Well... Collective wisdom has it that exceeding ~70hp at the wheel will give you a case of cracked casings...(mind you that's with the vibrations from the stock 360 setup) also pushing enough boost/ignition to top that is likely to cause overheating/detonation. So 70 is the target. I've done rough math on the pulleys and expect to build something like 6 PSI, with oversized copper head gasket to back off stock compression and better heat dissipation. Once running, tweaking pulley sizes to stay within that safe limit will likely be necessary...
So yeah, I'm taking the back road to what could have been done with known carb/cam/ignition/exhaust tweaks.

 

[Signal]

Love the engineering. The body work looks about right too. Keep chipping away you will get there.
(Edit)
Your last post appeared while I was writing this. There is info around on strengthening the cases. The rear engine mount and the top end oil tube boss are weak points I know off.
I have heard shot peening the cases helps.

 

[gggGary]

Wow, thanks for sharing.

Keep us updated!

 

[MaxPete]

Shot peening the cases will help...to an extent - but 6 lbs of boost may be a tad high. I'd be temped to start a bit lower and work your way up.

Also - you spelled Yamaha incorrectly on both sides of the fuel tank...

Otherwise, very cool!

 

[wannabridin]

Nice project, hope to see it finished and riding.

Also, when you're welding with that TIG, do us a favor and taper off the pedal at the end, every one of those tacks has a crater crack in the center. Would hate for that to happen in a structural area...

 

[TwoManyXS1Bs]

Do a forum search on "Aisin".
There's a 300 model...

 

[Jusblowit]

Do a forum search on "Aisin".
There's a 300 model...

Well aware, and that was a consideration for space+weight savings, but after some research I decided I likely would have had to spin a 300 too fast, possibly exceeding the unit's specified limit of 10k rpm, and also generating more heat than necessary. FWIW I'd rather have a bigger unit working slower.

 

[Jusblowit]

Love the engineering. The body work looks about right too. Keep chipping away you will get there.
(Edit)
Your last post appeared while I was writing this. There is info around on strengthening the cases. The rear engine mount and the top end oil tube boss are weak points I know off.
I have heard shot peening the cases helps.

Referring to the rear engine mount- the tab on the frame (pretty easy to reinforce) or the mounting "ears" on the engine? Wouldn't know what to do with those .

At any rate, for what it's worth and given the likely heat management issues with this engine, I'm happy to stay within established safe limits rather than go for all out power. This is going to be a street bike, not a dragster.

 

[Jusblowit]

Shot peening the cases will help...to an extent - but 6 lbs of boost may be a tad high. I'd be temped to start a bit lower and work your way up.

Also - you spelled Yamaha incorrectly on both sides of the fuel tank...

Otherwise, very cool!

Noted. According to my research that should be about the safe limit on premium pump gas if I drop static compression some (I'd have to look at my notes but I think I settled on something like 8.3:1). Still, won't hurt to creep up on that figure and/or leave a safety margin. I have two available safety mechanisms for testing/tuning :
1. Compressor bypass valve that can be set to open at a given pressure
2. I'm using fully digital ignition and there will be a MAP sensor attached. Beyond programming a boost referenced timing retard,I can set the ecu to cut ignition if pressure exceeds a certain reading, similar to a rev limiter. No way to run a bike, but a good fail safe untill I figure out how much boost my setup is making. There's also the option to install a solenoid activated valve to regulate boost relative to rpm but if rather avoid the extra complication unless absolutely necessary...

Re shot-peening, etc... "To some extent" being the key phrase. I don't really feel like exploring the limits....

 

[Jusblowit]

Nice project, hope to see it finished and riding.

Also, when you're welding with that TIG, do us a favor and taper off the pedal at the end, every one of those tacks has a crater crack in the center. Would hate for that to happen in a structural area...

I'll admit I had to look that up. No TIG, btw, that's MIG, the short bursts is me trying hard not to burn through the thin gauge tank while getting hot enough to penetrate the thicker plate I attached. I guess the proper technique is to walk it back into the pool before releasing the trigger? Live and learn... At any rate, since it is still water tight and I don't think will be subject to much stress in normal use, *and* I've already coated the tank, I'll leave it be.

After reading your comment I had a mild panic moment, and went back to inspect my welds where they *are* structural (-rear shock and linkage mounts, neck gussets) and the good news is my skills on heavier gauges are more adequate. Not winning the #weldporn awards any time soon, but I'm confident my rear suspension isn't flying off the bike.
Thanks for your feedback, I learned something new.

Proceeding to the spray booth.

 

[MaxPete]

Noted. According to my research that should be about the safe limit on premium pump gas if I drop static compression some (I'd have to look at my notes but I think I settled on something like 8.3:1). Still, won't hurt to creep up on that figure and/or leave a safety margin. I have two available safety mechanisms for testing/tuning :
1. Compressor bypass valve that can be set to open at a given pressure
2. I'm using fully digital ignition and there will be a MAP sensor attached. Beyond programming a boost referenced timing retard,I can set the ecu to cut ignition if pressure exceeds a certain reading, similar to a rev limiter. No way to run a bike, but a good fail safe untill I figure out how much boost my setup is making. There's also the option to install a solenoid activated valve to regulate boost relative to rpm but if rather avoid the extra complication unless absolutely necessary...

Re shot-peening, etc... "To some extent" being the key phrase. I don't really feel like exploring the limits....

Hi again JustBlowIt:

I certainly would "creep up on it" gently and I'd also suggest that you take additional steps such as having the stock built-up XS650 crankshaft welded for security.

As for the shot peening, the idea is that the peening puts the surface of the part into a slightly compressive stress state that makes it less likely that any tiny cracks will grow - at least for a while..... That is why highly stressed components such as connecting rods and certain gears etc. are often peened and it is also why drilling a hole at the very tip of a small crack and then "over-expanding" it (to promote a compressive stress field) can help stop the crack from growing - for a while.....

I would emphasize that the effect of the peening is pretty small and if you overdo the boost or RPM, no amount of shot peening is going to save your bacon. In other words, while it wouldn't hurt, don't count on it for much.

I am sure looking forward to hearing / seeing this puppy go though!

Hey - have you checked out the featured thread on the big CVMG Rally in Paris, ON in June? The featured marque (i.e. brand and model of bike) is the XS650 since it is 50 years since Yamaha introduced it. You should register at www.cvmg.ca and bring your bike along! This will be a big year at Paris and especially for the XS650 crowd.

I would suggest that you correct the spelling on the fuel tank or you might have two groups of big nasty (but slightly elderly) bikers upset with you.....).

Pete

 

[Jusblowit]

Hi again JustBlowIt:

I certainly would "creep up on it" gently and I'd also suggest that you take additional steps such as having the stock built-up XS650 crankshaft welded for security.

As for the shot peening, the idea is that the peening puts the surface of the part into a slightly compressive stress state that makes it less likely that any tiny cracks will grow - at least for a while..... That is why highly stressed components such as connecting rods and certain gears etc. are often peened and it is also why drilling a hole at the very tip of a small crack and then "over-expanding" it (to promote a compressive stress field) can help stop the crack from growing - for a while.....

I would emphasize that the effect of the peening is pretty small and if you overdo the boost or RPM, no amount of shot peening is going to save your bacon. In other words, while it wouldn't hurt, don't count on it for much.

I am sure looking forward to hearing / seeing this puppy go though!

Hey - have you checked out the featured thread on the big CVMG Rally in Paris, ON in June? The featured marque (i.e. brand and model of bike) is the XS650 since it is 50 years since Yamaha introduced it. You should register at www.cvmg.ca and bring your bike along! This will be a big year at Paris and especially for the XS650 crowd.

I would suggest that you correct the spelling on the fuel tank or you might have two groups of big nasty (but slightly elderly) bikers upset with you.....).

Pete

The CVMG rally sounds like a great event... It would take a small miracle for this bike to be on the road this summer, realistically there are just too many small details.
I'll have to come on my 500, which always gets interesting reactions, 8 out of 10 assume it's a 650, 1 is a 650 rider who is just baffled, and the other 1 had a 500 back in the day and gets all nostalgic.

Once pulling into a motel parking lot somewhere in southern Missouri some Dutch fella came around the building following the familiar exhaust note....turns out out he raced an xs500 for Yamaha in europe way back when, though I don't remember what type of racing exactly.
Apparently when a group of factory racers get drunk after the races and do their best to break the machines, you could break the Yamaha's and Honda's, but you couldn't break the Suzuki's. So maybe some of that will rub off on my supercharged bike... but don't tell the angry bikers I said that.

Incidentally, Yamaha is spelled correctly on my 500.

 

[wannabridin]

I'll admit I had to look that up. No TIG, btw, that's MIG, the short bursts is me trying hard not to burn through the thin gauge tank while getting hot enough to penetrate the thicker plate I attached. I guess the proper technique is to walk it back into the pool before releasing the trigger? Live and learn... At any rate, since it is still water tight and I don't think will be subject to much stress in normal use, *and* I've already coated the tank, I'll leave it be.

After reading your comment I had a mild panic moment, and went back to inspect my welds where they *are* structural (-rear shock and linkage mounts, neck gussets) and the good news is my skills on heavier gauges are more adequate. Not winning the #weldporn awards any time soon, but I'm confident my rear suspension isn't flying off the bike.
Thanks for your feedback, I learned something new.

Proceeding to the spray booth.

My thoughts were MIG as well, and in this case, your technique is sound (lots of spot welds). Structural welds should be fine, just get out the grinder and smooth them out and make sure you've proper penetration and no cracking. You can get by with thinner MIG welding w/ smaller wire, so get 0.023" solid wire or smaller if you can and run 75/25 gas. The other option is MIG brazing, using silicone bronze filler wire to get lower melt temps: https://www.millerwelds.com/resources/article-library/silicon-bronze-mig-brazing-basics Would be great for fuel fillers

I always recommend a professional if you're concerned w/ strength or aesthetics. I'll be taking my gas tank projects to a pro to have things welded onto them as I don't want to mess them up.

 

[FLEA]

 

[MaxPete]

The CVMG rally sounds like a great event... It would take a small miracle for this bike to be on the road this summer, realistically there are just too many small details.
I'll have to come on my 500, which always gets interesting reactions, 8 out of 10 assume it's a 650, 1 is a 650 rider who is just baffled, and the other 1 had a 500 back in the day and gets all nostalgic.

Once pulling into a motel parking lot somewhere in southern Missouri some Dutch fella came around the building following the familiar exhaust note....turns out out he raced an xs500 for Yamaha in europe way back when, though I don't remember what type of racing exactly.
Apparently when a group of factory racers get drunk after the races and do their best to break the machines, you could break the Yamaha's and Honda's, but you couldn't break the Suzuki's. So maybe some of that will rub off on my supercharged bike... but don't tell the angry bikers I said that.

Incidentally, Yamaha is spelled correctly on my 500.

yup - I had a 1979 GS850G and that thing was unkillable. It never, not once, missed a beat in nearly 100,000 miles that I put on it. It wasn’t as fast as a Kawasaki, it didn’t have the glitz of a Honda and it didn’t handle like an RD350 or 400, but it was a steady as a rock and it ran perfectly every time. It seemed to me that it was simply very well engineered with quite conservative factors of safety.