ZXR250 BHP.

[John]

what sort of dynos do these hit - getting a 92 zxr and told it dyno'd in at 32bhp (with aftermarket can) - sounds about right to me or should I check the compression?

thanks

[vifferman]

17.375, or thereabouts.

At a wild guess.

[FlyingDutchMan]

If its a 4 cylinder one (I don't know my ZXRs and ZZRs very well), it should hit 45HP. If it was built in 94 onwards, 40HP. The reason: That was what the Japanise law was at the time. 45HP limits for 250s which was changed to 40 in 93/94.

All the big four (Honda, Suzuki, Kawasaki, Yamaha) 4 cylinder 250s sports bikes produced 45hp in the early 90s.

It may have been restricted to 33hp to comply with some law somewhere else in the world, or the guy gave you the kw rating (33kw=45HP).

[John]

17.375, or thereabouts.

At a wild guess.

now thats just biteing the devils tounge :P

[jrandom]

32 seems a bit low, but then again, each dyno seems to live in its own unique little world of numbers. How do *other* ZXR250s do on that dyno? What do brand new stockers of various brands for which rear wheel BHP figures are well known measure at?

Does the bike happily pull to 180 or so in top gear? It should. Does it *feel* like it's making good power?

Certainly get the compression checked, though. Definitely. Never buy a bike without checking compression, brakes, electrics, state of the tyres, feel of the clutch, straightness of the discs, dirtiness of the plugs... the list goes on.

[John]

I'm pretty sure 40hp/45hp is the engine power at the crank?...

anyway I will go check it out - just wondered if anyone had some ideas on the sort of HP it should be pushing at the rear it was at the red barons dyno so yea dont know how good or acurate that is, thanks for the help all

[vifferman]

Certainly get the compression checked, though. Definitely.

Fergot.

Never buy a bike without checking compression, brakes,

electrics,

Yeah, it had some

state of the tyres,

Yeah, it had some of those too..

feel of the clutch,

Yeah, I clutched it a time or three...

straightness of the discs,

Yeah they were straight, but one's mental, or at least definitely inferior

dirtiness of the plugs... the list goes on.

I checked the colour.
And the pricetag.
And rode it a km or five.

[John]

I checked the colour.

quick head for an eye test, I have serious doubts about your color vision (PT)

[vifferman]

I'm pretty sure 40hp/45hp is the engine power at the crank?...

Yeah, usually the (exaggerated) crank HP is quoted by the manufacturers, whereas the dyno operators quote "at the wheel" HP.

anyway I will go check it out - just wondered if anyone had some ideas on the sort of HP it should be pussing at the rear it was at the red barons dyno so yea dont know how good or acurate that is, thanks for the help all

Didn't you mean "pussying"? :spudwhat:
I read somehweres that the "at the rear wheel" figure is about 15% down on the crank HP, which would make it about 34-39. However, the actual figure depends on:

• Dyno set up (calibration) and operation
• Air temp and pressure
• Frictional losses due to engine/drivetrain wear and tear, dirty/worn chain, etc.
• Rear tyre pressure.
• Why/who the dyno test is being done for.

[John]

yea I havnt actually seen the bike in person or anything and was just told about it it had new sprokets etc after 18,000k so I guess it was raped furiously..

Just was going to use the dyno reading as a point of figuring the engines health, so thanks for that there Mr VFR

[FlyingDutchMan]

I'm pretty sure 40hp/45hp is the engine power at the crank?...

anyway I will go check it out - just wondered if anyone had some ideas on the sort of HP it should be pushing at the rear it was at the red barons dyno so yea dont know how good or acurate that is, thanks for the help all

I just checked a ZXR250 manual - it should be 45HP. Even if it is at the crank, losing 13HP on the way to the wheel is shocking.

[jrandom]

Red Baron's dyno? I've seen ZXR250s that have done 41 on it, so your prospective bike is definitely down on power enough that you should be worried.

Don't touch it with a ten-foot barge pole. It's not worth the hassle. Find a mechanically sound one.

[John]

I just checked a ZXR250 manual - it should be 45HP. Even if it is at the crank, losing 13HP on the way to the wheel is shocking.

Yea I agree its a pretty rank loss of HP but I think that mainly relates to all the pooie cam chains and shafts (lol) that suck up the kinetic energy from the initial crank, and also I think they try to trick us into thinking that its around 45hp .. I think but I know absolute crap all so you maybe right my words as good as cottage chesse (read: bad very bad lol)..

thanks..

[John]

Red Baron's dyno? I've seen ZXR250s that have done 41 on it, so your prospective bike is definitely down on power enough that you should be worried.

Don't touch it with a ten-foot barge pole. It's not worth the hassle. Find a mechanically sound one.

I dont know that seems high I got more details about it 32.8 PS at 19.2deg amb it seems about right??..

[bear]

I've found this site to be useful: http://www.motorbikes.be/en/search.aspx
It's got the ZXR down as 45bhp/33.6kw.