http://www.sportrider.com/bikes/146_0110_suzuki_gs500/index.html

Gonna start dumpster diving at Boeing.

Nice.

Wow, that's quite a story.

I remember reading this awhile ago, i think there might actually even be a threa don here about it! that definately made me want to try mounting a head like he did, but i cant afford to break stuff like that

OK how do people figure this stuff out, maybe in about forty years i can think about doing something like this.

What would break is usually what has been pumped to the limit ... a GSXR750 head is fine, I dont think it will hurt the motor at all ... you do need the right pistons for it ... build the head to the 10's, and put in coffee can sized pistons and you're talking about a hand grenade. BTW a GS425 or was it 450 ... could stand the abuse a bit better, if I recall it had a roller bearing crank.
Cool.
Buddha.

I'm not so sure about how well the roller bearings handle power. They absolutely handle low-oil conditions better than our plain bearings. They don't handle being abused better - lugging roller bearings is a great way to ruin them.

But we have someone on the forum who has a turbocharged drag build making 100HP plus with plain bearings. The bearings on the GS500 are certainly comparable to those on bigger bikes, although oil to the rods might be a weak point.

This is the infamous "GS500 crank can't handle big power" story I remember reading years ago.

Interesting how the member building the Salt Flats GS500 figured he could get in excess of 200hp out of it without breaking anything, and I know he was/is doing a fair bit of dyno testing to confirm the performance of it.

Quote from: Agno on August 06, 2012, 07:05:43 PM
http://www.sportrider.com/bikes/146_0110_suzuki_gs500/index.html

Gonna start dumpster diving at Boeing.

i remember this story posted here when i joined this site in 2003. this one and motocat still recall  nearly verbatim. that bike kicked/kicks ass

So I have heard 2 things, The crank cant handle much power and the crank can't handle a lot more RPM.

Whats easier, this, or a kawasaki 650 swap...

Gary might disagree on the issue of how much power the GS crank can take.

http://gstwins.com/gsboard/index.php?topic=58391.0

Aye, I want to rebuild the GS for like 14-15K rpm anyone wanna help me steal some rods and pistons and valves from a LS7... TI FTW.

Quote from: crzydood17 on December 07, 2012, 01:31:29 PM
Aye, I want to rebuild the GS for like 14-15K rpm anyone wanna help me steal some rods and pistons and valves from a LS7... TI FTW.

Bore it and destroke it. Keep it 500cc, but make it a 18000rpm monster!!!

Not really a trivial mod. Did the math a while ago; even the maximum de-stroke from Ape would only get you a thousand RPM or two. You might be able to do a custom crank. Con-rods would help, custom pistons would help. The engine would make horrible power at those RPMs, so a custom valve-train would be in order. Even then, I suspect breathing would be a major problem for a 2 valve hemi-engine. Modern sport bikes have notoriously poor* Volumetric Efficiency (VE,) even with 4 valve pentroof heads - a twin valve would have even bigger issues.

* Poor VE is why a modern sport bike can run 87 with a 12:1 compression ratio. The mechanical ratio is very high, but the cylinders don't fill completely with air, so peak pressures are relatively low when the engine is running at high RPM.