1994 cr250r doesnt sound right

I just rebuilt the motor a few months ago and have rode it about 4 or 5 times. It has done this since the first run when it is at idle it sounds more like a one stroke it makes a blub blub blub soud instead of the rrriiinnnggginging sound the normal two stroke makes. When I rev it up or gas it it runs great has good power but bogs down from closed to 1/4 throttle and I have been running rich. I changed the pilot jet from a 55 to 52 and turn the air mixture screw 1.5 turns out and a 175 main jet. It ran alot better with those settings and didnt bog as much but still hasnt changed the way it ran when it idles also it is really hard to start it doesnt matter if its hot or cold

I think your piston may be in backwards, or your CRV wasn't in the right position...

Piston is in the right way I already put it in backwards once and I'm pretty sure the rc valve is installed correct I used the shop manual when I installed it

I'll start mine up tomorrow and record it for you, mine sounds like they should (:

pipe-to-silencer tight?

...everything sounds like a blown skirt to me lately...

this probably will not help but here is something to consider.since you took it all apart and seeing how it is a 94, you may want to pressure test the bottom end.i found that my intake boot was leaking really bad.not on the gasket/case but on the rubber boot to reed cage section.fixing this helped everything.did you also psi test the topend? i have a 93 i just brought back from the dead :bonk:

I think I know the sound you are talking about, I have the same thing on my 93. Can't say it has changed with a topend or a power valve cleaning either, and I think everything is in working order.

If your hardware is stock and you are going to try and jet it, have you followed the little chart the shop manual gives to use as a baseline?

Or what about a jd jetting kit?

For me I don't go nuts with the jetting because on paper, with all the altitude and temp changes, this is honestly too much work for us and the average joe trail riding we do.

But I can tell one way or the other when the bike is acting blubbery right off idle and it can suck at times. It actually slows me down in allot of situations I noticed.

With that being said, I am 280 pounds before gear and am not sure how much that plays into the snappy factor, plus I have the heaviest flywheel weight on my bike.

It has a pretty smooth power delivery, but the meat of it definately comes on and is most powerfull in the middle. It is very strong there, if I can keep it there, sometimes I can even ride a gear high. It kind of levels off at the upper end unless I am screaming it.

When you say it runs bad and it is hard to start, are all these things new to you since your rebuild?

My bike is easy to start year round on stock jetting. If I prop myself up next to a tree so I don't have to balance, and I have rolled the bike a bit with the gas on, I can get it to start on the first kick. As long as I position the piston at top, balance and get a good footfull and push through the peg, rather than a sloppy kick bacwards.

With the bike cold, I always start it with the choke on, no gas. If the bike has been warmed up like when you stop for a break for 10 minutes, no choke and a handfull of throttle.

To start I bought the bike in pieces for a few hundred dollars and it had a bad hot rod crank so I knew a guy and he got it warrantied for me. I had to bore it 60 over I did other upgraded such as all balls crank bearing and replacing the clutch with after market fiber plates with stock steel plates and heavy duty clutch springs. The bike came with an FMF pipe and a powercore 2 silencer that I re-packed. The pipe does have some dents and dings in it and I'm not sure if that would cause any problems with it or not.

I have not used a jet kit but I am running a 52 pilot jet, 175 main, needle clip is in the 3rd postion and the air screw is 1.5 turns out. The bike does run great in mid-range and top end and when I changed the jetting last time it did idle which is was an improvement.

Completely rebuilt 94 CR250 (top, bottom, everything!), all stock minus the Wiseco piston, running 190 main 72 pilot at 3rd clip at sea level. (yea its jetted fat, but the bike loves it)


This might be a stupid question but did you check you reeds? Does the bike make the power it should when riding it?

I listened to your recording and my bike sounds like it idles at half that speed but it does have good power when I ger on it but it feels like its not all there it takes a bit to get the wheel off the ground if I get on it. I did put new boysen reeds in it but I havent checked them since I installed them.

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