Transmission Issue

Hey guys,
I was riding my bike the other day for about an hour and when I started it again to go home I couldn't get it to shift into neutral or second. I noticed the clutch wasn't fully disengaging so I adjusted it all the way and it still won't disengage. I can get the bike to start by push starting it but it still won't go into neutral. I was hoping someone else has had this issue and might have an easy fix to it.

Also I took off the shifting mechanism cover and everything appears to still be moving but the shift drum is stuck.

 

There is a fairly large passage under the shift cover that runs between the shift rachet and the transmission. Shine a light in that hole and see if there are chunks of plastic jammed in the gears.

Also check to see if the shift return spring is broken. It is a small spring on the shift mechanism.

 

Okay so I did what you suggested and you nailed it on the head. There was a piece of plastic with some metal shoved through it stuck against the shift drum stopping it from rotating. Any ideas what it is/was?

 

That is a part of your primary chain guide. They harden and fail due to age. You will need a factory service manual, and the Haynes manual, and a fair amount of patience.

The remedy is to split the cases, clean out all the crap, and replace the guide. It is also a good idea to replace the primary chain, and the starter clutch since splitting the cases is a lengthy process. If you don't see any flakes of metal in the oil you can go ahead and ride it this season and do the work in the winter.

A couple of tips:

The process has a lot of steps, but each step is fairly simple. Take your time to read and understand what you will be doing.

There are a few special tools that are needed, but they are inexpensive and as the owner of a classic motorcycle you will find use for them again.

Loctite 515 or 518 are fantastic upgrades to Yamabond.

Chacal has all the parts you will need at very reasonable prices and with better customer support than you will find anywhere.

This thread covers the process pretty well: http://xjbikes.com/forums/threads/xj750-engine-removal-and-split-pictures.38545/
Note that you can cheat a little and can split the crankcases without removing the head or cylinders. This makes installing a new primary chain impossible, but the primary chain on the shaft driven bikes sees light duty compared to the chain driven XJs, so it is unlikely in need of replacement if your machine has less than 50,000 miles on it. On the other hand this is an excellent opportunity to replace all of the gaskets and inspect the engine internals in order to get a heads up on any other potential issues.

 

That's what I was afraid of hearing. I really don't have the room for splitting my cases and my bike has somewhere nearing 100k miles if not more now. I hate to have to get rid of this girl but I really can't devote tons of money and time into fixing her up. Thanks for the information K-moe. I'm gonna do some thinking and talk to my step-dad. Maybe some great source of money will just spring up and I can afford to do this work...

 

Total cost (DYI) would be somwhere in the range of $400. Compare that to the money you'd spend on a replacement motorcycle. You will come out ahead by fixing her, or finding a used engine with fewer miles (and an intact primary guide). I financed my primary guide replacement, and starter clutch replacement by taking a sack lunch for three months instead of eating my usual $10 takeout lunch.

 

Well I decided to just ride the hell out of it this season and see if it survived. I was putting by clutch together (step-dad thought it may have been a clutch issue the other day) and ended up sheering the head off of one of the bolts. I'm going to stop before I destroy anything else and part her out.

 

I might be interested in the engine. Start a conversation with me. Which XJ?

 

Sorry if I'm hijacking the thread

k-moe
I was just about to embark on replacing my primary chain guard. I found a piece of plastic in the shifting drum exactly like the OP. I was going to do the 'cheat' you mentioned and not remove the cylinder and head. I thought I would be able to replace the primary chain with this method, but as I read it you can't?

My bike is an xj650, which is shaft driven, and has 47,000km (which is only 29-30k miles) so as I understand the chain should have quite a bit of life in it still? If I don't replace it what should I look for while inspecting it?

 

Anything that might render it not serviceable. Also don't forgot to mark it upon dis-assembly (it must be returned to the orientation it is removed). Hope this helps.

Gary H.

 

So can you replace it without removing the head or cylinders?

I ordered the parts from Chacal and I ordered a chain. But not sure if I got all the gaskets that I may require to remove the head and cylinder, if it's required to come off to replace the chain.

 

You can not replace the chain without removing the connecting rods from the crankshaft, and the best way to do that without risking damaging the cylinder liners, or the bearings is to do a teardown of the top end. If you go that route you should go ahead and order all the gaskets that the engine has and replace them since the engine will essentially be completely torn down at that point

Im ny opinion, at 30K there really is no reason to change the primary chain. It is a HIVO chain and they have a very long service life. I would expect that you would not need to consider changing it until well after 50K miles. The primary chain in the shaft driven bikes is only used to spin the alternator, and to spin the engine when the starter is engaged, so it is understressed compared to a true primary chain which links the crankshaft to the transmission.

 

Ok well I'll inspect it for excessive wear but will most likely leave it.
Thanks appreciate the help!!

 

Anyone know if the clutch has to come apart with the "cheat" method of replacing the primary chain guard?

 

i don't know what the "cheat" method is but once you're in that far the clutch is child's play

 

It does. You have to split the cases, and the clutch has to come out to do that. The "cheat" is to leave the top end alone and only split the cases (this precludes replacing the primary chain and the cam chain).

Be really careful when removing the chain guide mounting bolts. The heads can break off (particularly the one closest to the crank, which is reatined by a threadlocking compound (apply some heat to help it break free)). If one does break, stop what you are doing, tear the top end down, and take the upper case to a machine shop to have the remainder of the bolt removed.

 

Stupid question I guess...How do you know when it's time for a chain replacement along with its guides??

 

There is no set metric for that. Chain free length should not be excessive, and there should not be any visible damage to the chain. That is all the factory manual has to say on the matter. I doubt that a primary chain would need to be replaced before 50,000 miles, but you have to weigh that with the need to tear the engine down again to replace the chain if all you are replacing is the guide.

 

That on the visible part I mean when you open the engine. But there is any sign that you should be on the lookout that tells you it's time to replace that chain? A noise or something?