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ok so i have talked to a few locals as well as searching the **** outta this site it seems that the problem is the bike(93 kdx 250)is not hitting powerband.
just wondering if u guys could share on the most common causes for it not to hit band.
a few ppl ive spoke to said reed valve but i have checked it and its not broken or anything.
all help is greatly appreciated

just wanna ride the damn thing lol

KIPS....

kips is working as it should as in visually checked both ports open and close when valve is operated.
anything in particular with the kips?

I don't know too much about the 250's but could you tell us your jetting, needle, pipe and gear ratio?

It is usually the port timing that causes the bike to hit the powerband at around 6K RPM's. The pipe has an effect as to how effective that is along with all the rest of what I stated.

r1inoz wrote:kips is working as it should as in visually checked both ports open and close when valve is operated.
anything in particular with the kips?

Do you mean "operating" as in you operate it manually, or does it operate when it's running and you rev it up?? On the newer 200's and 22's there's a cover you can remove on the left hand side and watch the kips operate when you rev it up. Not sure if this is on the 250's though.

it operates when i rev it.
and inda i bought the bike as not running so im not sure what the jetting gear ratios are.the pipe is the standard pipe.

If the drum gears are stripped (Common) It will actuate as far as you can see but will not function beond the vertical rods going into the cylinder.

That the main shaft turns when you rev it doesn't mean the KIPS is working.

You say the ports visually check out..but then say the rod moves when it's revved.

Which is it?

Both need to be checked: That the valves work when you manually activate them..THEN that the bike activates them.

The #1 reason a 2-stroke doesn't run like it should is that it isn't jetted correctly.

THAT is true when mechanical issues are known good. Compression, reeds (you checked them..that they are not broken does not mean they are any good. Reeds lose their tension over time. They may 'look' good..but still won't work right), tight airbox, clean filter, clean carb, an exhaust pipe that's not dinged half shut...etc.

Are you sure it is revving up enough like hitting the rev limiter enough? I don't have this problem as the PO put a brand new powerband in it before getting rid of it.

250s have rev limiters?

I'm not saying this is right, but it IS the way I thought things are:

The Web wrote:No 2strokes do not have rev limiters, they simply reach a point where the port timings and exhaust resonance will not allow it to rev farther.

...and...

You won't "blow" a mechanically sound two-stroke by over-revving it. If the engine is tight and within specs, you can hold the throttle open until the engine stops revving. They run out of breathing ability long before they run out of safe rpms.

From HERE!. Listed as one example of many such statements of absolute truth. I KNOW it's true 'cuz I read it on the web!

**edit**
After reading a few multi-page blabbers by a lot of people having no understanding of the English language: A 'rev limiter' is by definition (mine) a device built into or added onto an engine which existence is for the sole purpose of preventing engine RPM from exceeding a particular number. A rev limiter is NOT an engine tuned to a particular power band for whatever reason, it is NOT an engine which, by design, cannot/will not exceed a particular RPM.

How about the rev limit. I read THAT in the enternit fourum that I go to allot.