Transmission Problem

[easystroke]

When I shift into third gear I hear a knocking noise. Is this a common problem? Could this be the mainshaft gear and/or the countershaft gear. It only does it it third.

[beak7707]

Yes, tranny problems are an issue in the 250's. Those trannys have taken a hell of a beating over the years. I can't tell you exactly whats wrong, but something is going wrong. I would recommend tearing it down and taking a look in there. It will be alot cheaper to do that then wait for it to explode a gear and ruin everything. Hopefully somebody else will have a little more info for you.

[bighaas12]

As stated previously, this is a very common problem with the 250r's. I just receintly replaced 4th gear in one of my R's. DONT WAIT!!! unluckly for you and I 3 gear and 4th gear on the main shaft are made in one piece. So replacing one is doing both. I would highly recommend replacing the opposing gear on the countershaft as well. Mine was not totally destroyed but all the teeth were bent over and metal shards were found all over the motor. One more lap and it would have been BIG problems. Only way to fix it is to split the cases and get in there. Not too bad a task with the manual in hand obviously. Take your time and be very very organized with the parts during disassembly. Keeping everything in order and seperated is the hardest part of the whole job. The manual from honda was great, there are alot of pictures to help out. Make sure also to use some type of gasket sealer (high temp) on the center gasket just to be sure it doesnt leak. Mine had a small leak after total assembly. This is a great time to replace bearings in there as well. It is not cheap the gears run about 60 to 100 bucks from honda. Check your clutch basket for wear as well. I am not telling you to build a new motor but the time and effort to split the cases is worth throwing another 100 to 200 at it if money permits as to not have to go back in there 6 months from now. Hope this helps...... good luck!

[AAracingFMX]

When you think of it, almost every 250R has been raced one time in it's life, and when you get an 18 year old machine, parts will get weak, like tranny's on the 250R. DON'T WAIT!!! I had a tranny granade on me new years day during an ice race, it wasn't pretty...second gear on the countershaft shattered into 12 pieces, it didn't spread throughout the tranny(thank goodness) but it did do a number on my case, a real big number:grr: With buying a 95 dollar second gear, I also had to purchase a new case, which was an additional 350 bucks, so unless you want to pay that much extra, go ahead and wait....i'd suggest tearing it down as fast as possible. A trick to the trade is putting 1 and 2nd gear from an atc(85-86) into the trx motor...the gearing is a bit lower and more spaced out, you'll notice it if you do so. Make sure to inspect the shafts themselves where the cir-clips seat into, make sure they are not worn at all as well as the dogs on the sides of the gears that lock eachother into place, makes sure they are squared off and not rounded. Good luck, if your doing it by yourself, then I'd recomend getting a manual.