is my top end going?

my bike has about 35 hours on it. (approximatley) while i was riding today everything ran fine and sounded good other than the fact that it has been getting harder and harder to start. (still has good compression) but when i went to practice my starts while revving the bike out and about to release the clutch it sounded really odd almost like i was over revving it. ALOT! but i wasn't. is it about to blow? i'm ordering a new top end tommorow anyways but it wont be here until next week and i have a race saturday.:thumbsup:

anyone?

Im not to sure about what was causing the extra revs if you were not, Id say check you clutch.

sounds like ya have 2 choices race it and hope nothin happens or pull a noshow and make the next one,my 125 does that once its getting ring wear and is a little more anal about starting as well with the little screamer bikes like your 85 and my 125 its not unusual or expensive to change them alot anyway. so you have 35 hours on the same piston/rings?

Hmm, well i think that you could race, but that is just all up to you. I would say that you should check your clutch, top end, and even your jetting maybe. If it is revving weird, your needle jet for the throttle may not be functioning properly

drain your gas out of your tank and drain and clean your carb. then put fresh gas with fresh mix in it also. dont use the same gas that you had in the bike..

to me it sounds like you might have some water in your gas causeing it to get harder to start and the revving..

if your topend was going the bike would be easy to start not harder.

I'd be willing to bet on one of the following.

-Either your clutch is about to be fried.

-Or your clutch cable is adjusted too tight, and your clutch is not fully disengaged.

Trust me, ive lost a clutch to the second one. It pisses you off because is is somthing dumb, and it is easily prevented. Check it, if that dosent work, check the plates for wear.

And if youve never put a clutch in, dont worry, its probally the easiest engine work you will ever do.

Id rather do a clutch that clean a filter, if you know what i mean (and i find filter cleaning easy also).

Good luck

i dont think it's my jetting because it revs fine during normal riding but for some reason when i rev it up like you supposed to right before the gate drops it sounds weird like its over-revving.and yes ive had the same piston and rings for 35 hrs.i might try draining the gas though.

If your compression is good then it isn't the top end. If it is over reving, that could be a sign of it being too lean. It may be an air leak in the engine somewhere. I just had it happen to me on my 01 RM 250. You might want to do a leak down test. If it is an air leak if it's not a bad basket around the carbs it could be a leak in the bottom end (crankside seal, etc.). Do you see any coolant in your oil? An air leak in a 2 stroke will make it run lean. Problem is you will destroy your cylinder because you won't be getting enough lubrication. Not trying to scare you, but without hearing the bike run I can't tell you for sure.

If your compression is good then it isn't the top end. If it is over reving, that could be a sign of it being too lean. It may be an air leak in the engine somewhere. I just had it happen to me on my 01 RM 250. You might want to do a leak down test. If it is an air leak if it's not a bad basket around the carbs it could be a leak in the bottom end (crankside seal, etc.). Do you see any coolant in your oil? An air leak in a 2 stroke will make it run lean. Problem is you will destroy your cylinder because you won't be getting enough lubrication. Not trying to scare you, but without hearing the bike run I can't tell you for sure.

X 2, probably an airleak

how do i do a leak down test?

If your leak down reveals nothing then it also could be a bad throttle cable. Check the linkage and where it connects to your slide in your carburetor. It could be all kinked up or the spring may not be returning properly.

You need a test gauge and adapter for your spark plug size. However, that test is for compression. "Leak Down" means how long you cyinder will hold pressue, and how much pressure it is making.

It could be your reed block, intake, even a loose pipe with a bad seal can sometimes have the same result. It could also be a leak in the base gasket. One way to check is to start the bike and turn the idle up slightly so the motor does not die. Take a can of starting fluid and give a light (just a quick shot) onto the suspect area of the leak. If the motor revs up, you have probably found your leak. Remeber, don't fog the motor, just a light shot where you think the leak might be. Do not spray into the air cleaner or intake of the bike, it could cause damage to the motor.

I would be willing to bet the leak is around the intake or reed block.

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