zzr 250 what motor can i use?

[nick28]

i have a 1991 zzr 250 and motor has gone just wanted to know if i could up grade to a bigger or newer motor that will fit in the fame and what other mods i need to do to make it work thanks for ur help

[waynemorgan]

I could be wrong but the motor in the ZZR250 and the GPX250 are the same motor - should be a straight swap.

[nick28]

thank u will look into it

[MrWasabi]

the EL250 has the same motor too, although the radiator is different.

Edit: dont know if you could fit anything bigger in that frame. If you want i have a zzr250 sitting in the garage collecting dust i am happy to part out.

[Gosling1]

same motor (basically) in those bikes for the last 20-odd years mate - you should be able to get any later-model engine fitted without too much trouble, but they are not any quicker or more powerful...

[Slow and wobbly]

same motor (basically) in those bikes for the last 20-odd years mate - you should be able to get any later-model engine fitted without too much trouble, but they are not any quicker or more powerful...

Unless you get the original fire breather GPZ250R motor that had a different valve grind and could go 34mm(?) carbs gives another 2 horses - add a 2 into one and some pods with jets and stand back for another pony to be unleashed.
Still not worth all the effort though. Just head down to the wreckers and fetch a GPX or ZZR 250 engine, bung it in and ride it.

[mike-s]

however r.e. the el250, zzr250 and gpx250 the former has shorter gearing to facilitate the fact it's a cruiser as well as a different cam to the latter two. Also i suspect the cam profile may be slightly different between the gpx and zzr 250's, not that you'd notice. But yes, el250=shorter gears and much milder motor.

[MrWasabi]

Good point mike, didnt know about the gearing
come to think of it, dont the new ninjas use the same motor?
They sure sound like a ZZR

[ShamZX11]

Yes... EL250 have different gearing compare to ZZR250. Rear sprocket size for EL250 = 44, ZZR250 = 47. But EL250 has a greater torque/ pickup. Guest what... replace ZZR250 rear sprocket from 47 to 44 and you will get extra 20km/h in full throttle/ top speed.

[Gosling1]

Good point mike, didnt know about the gearing
come to think of it, dont the new ninjas use the same motor?
They sure sound like a ZZR

they use *basically* the same motor that has been around now for 20+ years yes slight detail differences with the early model cams, but the important thing is that you can just about bolt any 'version' of this motor into a '91 250 frame, gear it appropriately.........and away you go.

[mikk]

yep all zzr250 and gpx250 motors are basically the same. very slight differences over the years but nothing significant. i'm interested though to see if anyone has actually put a recent ninja 250r into a zzr.

as for putting another motor in, well i don't think anything bigger fits without significant modification to the frame. I heard of someone trying to put a 400 in and hacking up the frame years ago but i think that's where it ended.

[ZZR250-PT]

same motor (basically) in those bikes for the last 20-odd years mate - you should be able to get any later-model engine fitted without too much trouble, but they are not any quicker or more powerful...

Hello Gosling *waves.
Yeah man..essentially the same motor for over 20 + years. Had a GPX and now a ZZR2fiddy, simular bikes.

[mike-s]

Most noticeable changes are
1) exterior of the engine is slightly changed over the years and looks a bit better,
2) clutch actuation mechanism is slightly different in the way it is designed, but does the same job.
3) minor internal changes to the engine.
but things like monting points essentially remain identical, so it can in theory be pretty much a swap-n-go arrangement.

[bonester]

yep all zzr250 and gpx250 motors are basically the same. very slight differences over the years but nothing significant. i'm interested though to see if anyone has actually put a recent ninja 250r into a zzr.

Old thread I know but hopefully of some help. I have now fitted a Ninja 250 engine to both a GPX and ZZR250. They don't fit but can be made to. Differences are sprocket cover, front sprocket on ZZR, coolant lines out of the head, inlet manifolds, exhaust arrangement (worst thing) and front engine mount out of cylinder head is 10mm wider on Ninja- attack it with a hacksaw and grinder to make it fit. Not the neatest fitting but functional. Engine has some updating done- stupid rocker system of GPX and ZZR is gone- underbucket shim in Ninja. My ZZR had two broken rockers and a bent valve thanks to someone setting valves too wide, or maybe just stupid design. Wrecker told me common to find broken rockers in these engines.

[bonester]

I'd like to try a Ninja 300 engine conversion too- minus injection.