Hey everyone. I just got my R put back together friday, for a busted case, and it did it again yesterday! The 1st time, I was going around a corner, and the chain came off, and busted it. Now I know you guys are going to tell me to get a casesaver, but the holes that it screws into are messed up, so it wouldn't go in.

Anyways, I put it all back together friday.. Got new sprockets and everything! I JB Welded the case last Tuesday night, and put fluid in it thursday. It had no leaks.

Last night, I unloaded it off the trailer, got on it to warm it up before practice, and my clutch perch snapped.(For NO apparent reason) So I went and bought a new one, put it on, and got ready for my practice. Well, my practice was up while I was putting the perch on, so I only got to ride 2 laps... Or so I thought! I pulled onto the track.. Got in front of a friend of mine(300ex) and was going to get some hard riding in since I only had a couple laps. Well, I did a small(but hard) double, made a berm corner, got on the gas, and nothing happened. I looked down, the chain was spinning on the sprocket. I knew what happened though. I stopped, put the chain back on, and took off again. Made a double, corner, another double, corner, a big double.. same thing. This time it busted the case.. AGAIN.(These cases are $200 from Service Honda)

So really what I want to know is what could be making it do this? The more I think about it, the more I want to wonder if the countershafts aren't aligned. Is that possible? I'm running an LSR Axcalibur +4 axle. Thanks for all your help, I'm going to need it.

And if anyone knows where I can buy a good case, for less than $200, please tell me!

 

Are you sure you have the proper tension on the chain? It could be possible that your sprokets aren't alind and it could be coming off.

 

I'd say you either have worn chain and sprokets, an alignment problem, or are not tensioning the chain correctly.

 

I dont know much about the R tension setup, but it could be that after you set the tension on the chain and ride it alittle the bolts loosen up on the swingarm and free your chain tension because of the carrier being able to move around. I had to use lock washers and locktight on my old 250x. Just a thought.

 

check and see if your front sproket is on the right way. some sprockets have spacer or are off set.

 

Check the swingarm pivot and bearings. If they are bad, they will allow a lot of movement and throw the chain. This should be checked on all used 250R's. You may need to take the pivot out. Also, if your chain is used up, it can come off no matter how tight you have it. Take the chain off and see if it will flex side to side. If it does, aim it at the trash can.
Finally, if you had your case repaired, it might not have been properly done and the countershaft might not be 'square' with the bike. If you are having to use JB Weld, it doesn't sound like a good job.

 

The swingarm was loose when I bought it. I tightened the bolt, and it doesnt move any. The bearings are still good. I don't have my Clymer yet, so which way is the sprocket supposed to be on? With the spacer on the outside, or towards the motor?

The chain was 2 fingers in the middle of the swingarm. That's the common measurment I have used on all my bikes, and never have had any problems

Now the chain on the other hand, it's a 520 DID. It MIGHT have been worn out. I bought a new one, but it hasnt come in yet, so I used another sprocket. It was a 38 tooth off a 400EX.

It's not a big deal that it busted the case, I just want to know how to fix it so it wont happen again.

Thanks guys!

 

Its soumds like you have a few problems that is causing the chain to come off. First the washer goes betseen the case and the sproket. The sproket should be flush with the end of the shaft, if not add or remove washers. The old waay tocheck a chain to see if it is shot is to grab it on the rear sproket at about 3 or 9 o'clock and pull it away from the sproket. If you can put a pencil between the sproket and the chain, it is shot. Time to get a new one. The main thing that you need to check is your swing arm bearing for wear. Put your R on something so that all 4 heels or off the ground. Grab the rear wheels and try to see if there is any sideways play(not up and down). If there is any play the swing arm bearing are shot and it sounds like that is your problem. Good luck getting them out if you have and 88-89.

 

I had the same prob on my 86 it used to throw chains all the time.Even broke my case.


MY dad is a sheet metal worker and he took it where he works and his freind tig welded it.I got the shift shaft straightened and was on my way.I also got a nac's casesaver.

Well after about 2 rides it broke the casesaver.I couldn't figure out why.I had just replaced the bearings and seals in the axle and the swingarm pivot bearings where fine.

I finnally replaced my chain and sprockets with new one's and the chain hasn't come off since.


Another way to c if a chain is now good is to c if it moves from side to side if it does it is shot.


86 trx250r setup for mx
97 300ex getting setup for woods

 

My swingarm bearings are not out!! I have checked that 15 times!

My front sprocket has a spacer on it(not washer) that sticks out a centimeter or so, and I put it to the inside. Then, I put the washer(in which has OUTSIDE engraved on it) to the outside. Then put the bolt in.

I WOULD weld my case, buuuut, there's a hole in it the size of a shotgun shell turn sideways!