Transmission rebuild '82 XJ650 RJ

Greetings! First my story: Bought my first bike ('82 XJ 650 RJ) almost 3 three years ago. I knew it needed work, got a Haynes manual and the XJ CDs, did a lot of electrical and basic stuff myself. Had the carbs rebuilt when I took it in to get certified, then found out I have the infamous 2nd gear problem, a bad oil leak, and the neutral indicator doesn't work. Bike was left in garage untouched until recently, pulled the engine and this past weekend dissassembled it.

A friend has been helping me as I learn about engine rebuilding, but now I need some of your expertise! I've been browsing the forums for a while and I know I've come to the right place.

1. The oil leak is obvious, PO used a silicon based case sealant which squeezed out and is everywhere... the oil pump screen was completely clogged! What's the best method to scrape it off the cases without causing damage?

2. Neutral indicator switch: How does it work? If I put my volt meter on the screw and on the engine block should the switch close the loop when the gear selector drum is in the correct location?

3. Transmission... I'll leave that for another day, several photos will need to be posted.

Thanks in advance for the help!

 

Whats the "infamous second gear problem"?

 

It pops out of 2nd gear into neutral when the engine is under load (accelerating hard). Apparently, it's quite common with these bikes. The dogs on one of the gears wears down and won't stay in place.

 

Hmm, I have trouble shifting into second from first under high RPMS but thats about it

 

Just FYI - my second gear issue was solved with a new selector fork. Never touched the gear dogs.

 

Thanks Robert!

What does RTV stand for? I'm pretty sure the PO used the wrong stuff, it reminds me of silicon caulking used for plumbing (but bright orange). I'm going to try and remove it tonight.

What should I be looking for when examining the shifter forks for wear? Are there any specs on thickness etc.?

 

Look for burn marks or gaulding. If found also look at dogs and slots in driven gear.
Use laquer thinner for cleaning RTV from cases. Clean surfaces one more time with thinner to remove oil before reassy. Use yamabond4 or three bond (same stuff) Squeeze some on finger and wipe on case surface. it will only stick to case if all oil is removed with Laquer thinner.
Second gear fails with abuse. Ride it as it should be ridden and trans will be trouble free.
Good luck

 

RTV =Room Temperature Vulcanization

 

= silicone.

Very similar to silicone caulk.

 

Thanks for all the input so far.

I had noticed that the dogs (and corresponding slots) don't seem very worn. I took a closer look last night and here's what I've noticed:

- the #1 shifter fork appears black, not shiny and smooth like the others (see photo).
- the corresponding gear (5th gear pinion?) on output shaft appears darker as well
- 1st gear pinion on output shaft is quite loose, is discoloured, and the collar (?) appears to have some brass build up on the inside (or is it broken off?), some of which I found on the output shaft... (see photos)
- output shaft by the 1st gear pinion is also discoloured.
- there are some lines on the 2nd and 3rd gear pinions (see photo). Are these normal?

What do you think? I have a feeling my best bet is to take it all to a dealer to take a look at. But I want to make sure that I know as much as possible before going in so that I can make an informed decision.

 

JBerg, the discoloration you're seeing is called corrosion. This is from sitting a long time without having had a fresh oil change before storage. The acids suspended in the old oil have etched the metal leaving behind those lovely "age" spots. It appears light and I would not worry too very much about it if it were my bike. This can be a bad thing if it gets deep enough but I don't see that here.
You should be worried about that 2nd gear pinion and shaft. No bueno amigo. Something got in there and that brass shouldn't be there. What was the source of that brass??? Looks like time for a new pinion bearing sleeve and the shaft should be cleaned up.
The grooves on the gears are normal, they are made that way. No worries there, everyone's got them. It looks to me that the two inner gears on your last picture have some galling on the tips of the gears, is that oil w/dust or do my eyes deceive me?
As far as your forks, mine are coated with a dark brown/green coating. Does that sound about right concerning yours? I expect that it is an anti-friction/corrosion coating from the factory.
Best I can do for you with my limited knowledge. There are others here that know far more about the selector section than I'll every know. I also expect they will offer their two cents in a short while.
Glad to see your moving along.

 

I've never had one of those gears in my hand, but the picture sure looks like failure of a crankshaft main bearing. Looks like there is a cylinder of babbitt pressed in there. Got hot and chewed up the bearing.

The bearing isn't shown in the parts list. The gear comes with it in there. Probably need to replace the gear.

That is going to be just like a camshaft bearing. Depending on the cost/availability of the gear it might be worth taking some measurements and trying to scrounge one up.

 

I don't think there is much corrosion at all, might be dust you are seeing. The discoloration I'm referring to might be related to overheating of some parts. Very noticeable blueing of the 2nd gear pinion, some noticed on the shaft at this location too.

The shifter fork on the other hand looks like it might have heated up and had grease/oil "cooked" on to it. Hard to tell if it's been over heated.

I think you are both correct, failure of the "pinion bearing sleeve". The "brass" (or babbit) on the shaft is loose, I just left it there for the photo.

If some of these parts were overheated am I better off to replace them rather then having them fixed?

 

Overheated or heat treated is a question that comes to mind.

 

Rick's been absent in this thread. Bet he knows if the forks are heat treated.

Rick - paging DR. Rick. You have a call on line 1.

 

I'm back, had to take care of... life. Anyway, a friend was looking at the gears and noticed something that I didn't. Is the 1st gear pinion on the output shaft supposed to look like the photo below?

 

Are you refering to the blueing on the gear or the chewed up bearing???

 

Temper color Temperature °C Objects
Pale straw 230 Planing and slotting tools
Dark straw 240 Milling cutters, drills
Brown 250 Taps, shear blades for metals
Brownish-purple 260 Punches, cups, snaps, twist drills, reamers
Purple 270 Press tools, axes
Dark purple 280 Cold chisels, setts for steel
Blue 300 Saws for wood, springs
Blue 450-650 Toughening for constructional steels

these are the colors steel turns as it gets hot
it looks to me like the blue is closer to the teeth as in a heat treat process
when they made it, blue is like 650 to 1200 F i don't think it got that hot in there

 

Sorry, I should've been more specific. The circled area below, is it supposed to look like that? or has it been worn down by the dogs on the gear beside it? I assume that a new bearing could be pressed in if that is the only problem, but if the "spoke" is not supposed to be worn down like that then I will need to get a replacement gear.

Thanks Polock for the info, I'll be keeping that on file for future reference!

 

thats how it's supposed to look

 

In case someone reads this thread in the future I thought I'd close it out with some of the things I learned... be warned it's a long!

As there was noticeable wear on some of the gear dogs, and one of the shifter forks was very worn, I decied to buy a set of gears off eBay. Ended up buyring two, one was just the gears, the other set because I couldn't get the shifter forks seperately... try and buy everything all at once!

I decided to use one set of gears instead of mixing and matching. Installed everything but couldn't get the cases to join properly, when ever I started to tighten down the case bolts the gears would lock up. After much head scratching I realized that one of the gears was slightly larger than the original set (my case is a 4H7… part number the offending gear had 4L6… marked on it). Changed out the one gear (cleaned off the now dried out RTV) and everything went together nicely. Make sure you get the exact gears that match your bike, and do a dry fit before getting out the RTV. As you reassemble the engine make periodic checks to ensure everything is working correctly.

When putting the RTV on don't use too much. I believe the last guy to rebuild this engine used way too much and it clogged the oil pump, this in turn caused the bike to overheat and I believe this caused (or at least contributed to) my gear issues. I used Permatex - Ultra Grey, excellent product. Put a little bit on and then spread it so that you get a nice even coverage of the mating surfaces.

Be careful during reassembly. These bikes are old and so are the bolts, I broke a couple during installation. It's a good idea to know exactly where each bolt came from, makes life a lot simpler. Get a piece of cardboard and cut 40+ holes (or X's) Number them and then insert the bolts in the corresponding hole. I misundertood this part of the advice elsewhere in the forum and figured I didn't have the space to lay out 40 bolts on a huge piece of cardboard without them rolling off …

I tried to do this on a very tight budget. It can be done, but it will inevitably take you more time. Trying to find the cheapest parts on eBay, not knowing if the parts you are getting are in good enough condition, finding out that you need additional parts… all this stops progress and takes time. It is also hard to know what parts need to be replaced and what parts are ok without some advise from someone with some experience. For example, I didn't realize that most gasket kits do not include all the seals that you will need…

Make sure you know exactly what model bike you have. I thought I had an XJ650-RJ… turns out I have an RJC. I only discovered this when installing the head gasket and was trying to figure out why it didn't have the YICS ports on it… more time lost acquiring the correct gasket.

Not having a garage to work in will definitely slow your progress. I rebuilt the engine in my furnace room, but you can't use harsh cleaning chemicals indoors for extended periods of time, especially in the presence of the pilot light from the furnace! Waiting for good weather, and running out of daylight really sucks when you're just itching to ride.

A manual (factory, or Hayne's) is invaluable, as is this forum. All the information is here somewhere, yes it can be a little hard to find but it's here (that's why I don't have many posts). And the members are great and always here to help!

I got everything reassembled and reinstalled. One of the floats got stuck during reassembly and diluted all the oil with gas… once I got that sorted out she started right up! Needs a bit of fine tuning but she's running and I just got her registered today! I can't believe it's raining…