New member, have question.

[Antony250R]

I have an 88 250R, it is all stock except for the ESR TRX5 pipe. It runs good but one thing I noticed is that it only has midrange power, when it revs up the power goes flat. I used to have an 85 250R three wheeler and that thing pulled hard all the way even whith the stock exhaust.
Is it normal for a 88 250R to have such a short power band?

[Antony250R]

Second picture with the ESR exhaust.

[Dave83]

Check the jetting first.You can try bumping the compression up with a thinner head gasket.Get the jetting and needle clip position right first.

[MXRACER86]

That thing is SWEET!:macho

[250r4life]

its a beautiful thing... man i swear the 88 & 89rs have to be the best looking quads ever made... well, the best quads ever made too, but we wont get into that :devil:

LOLOLOL

man that first picture had me like .... Waahhhh? how he get that to float in the air??? LOL

then my brain fart was over and i noticed it was sideways :)

Nice quad.....

[wilkin250r]

Have you verified that you jetting is spot-on? A rich condition will often kill power in the upper revs.

To answer your question, no, it's not usual for a 88 250r to have a narrow powerband, unless you specifically set it up that way. If you're not entirely sure about what you're doing, talk to some race shops (not your local dealership, they don't deal with high-performance ATVs all that much).

[Antony250R]

Hi, thanks for the replies. It has 175 psi after 6 kicks on a hot engine, and I am running a 155 main jet, the stock main jet was a 158 I don't know if I should lean it anymore. The spark plug is a light brown color. I swithched plugs to a BR8ES from a BR9ES it runs slightly better with the 8 range plug.

[ddbyrd]

Why did you lean it out after installing the pipe kit?????

You are increasing the air flow, when ever you do that you need to add fuel as well.. Re-install the 158 main abd try it again, it sounds to me like you are experiencing a lean condition..

I have (almost exact set up as you) but I run a bills pipe and I run a 158 main jet it it halls the farm, pulls all the way thru the power band.

I run 10 paddle sand skate II's as well....

What are you doing for an air cleaner?????

[beerock]

whats your gear ratio?

[Antony250R]

Honda jets them extra rich at the factory. The 89 comes with a 155 main and the 87 comes with a 152 main. I tried a 158 and a 160, the 160 was too rich it bogged really bad and the 158 feels the same as a 155. My gearing is stock at 13/38.
I recently put in a thinner head gasket .010" thick, the power hits harder but it still has the same short powerband. The engine revs but it feels flat on the top.

[beerock]

you need to check your compression.

also, id throw a 14 sprocket on the front. and go buy a case saver.