Hi YamYam, try posting your own post in the garage. This is an old file, and only pertains to splitting a case. I can see you wanting to split your case, but at this stage of trouble shooting, you need to start with some basics. like explaining, what seizing means to you. Then we can interpret that, in to Yamaha-ise.
-
Enjoy XS400.com? Consider making a donation to help support the site.
XS400.com receives a small share of sales from some links on this page, but direct donations have a much greater impact on keeping this site going.
HOW-TO: split your crankcase
- Thread starter volcomskater77
- Start date
-
- Tags
- how to
Hi,
I know this is an old post, but I searched around and couldn't find any more information. I have a crack along the lower engine case along the drain plug. I found someone who can weld the crack and fix the threads for the drain plug, but I need to split the crankcase so he can take it with him to weld.
Can I split the crankcase with the engine still on the bike? I don't have the ability to remove the engine, so if I can leave it in place and still split the crankcase that would be amazing.
Thanks!
I know this is an old post, but I searched around and couldn't find any more information. I have a crack along the lower engine case along the drain plug. I found someone who can weld the crack and fix the threads for the drain plug, but I need to split the crankcase so he can take it with him to weld.
Can I split the crankcase with the engine still on the bike? I don't have the ability to remove the engine, so if I can leave it in place and still split the crankcase that would be amazing.
Thanks!
LuckyEight
Head-scratcher
It's impossible to split the case in the frame...
That is what I did, when I blew out the kick start journal. The engine is one of the lighter engines to carry. (take that you V-Star, HD, and other heavier motors) 
I had a base for my 16 gal wet dry vac, that I just placed my head into While I worked on the case. (drained of oil, first...) 
I had a base for my 16 gal wet dry vac, that I just placed my head into While I worked on the case. (drained of oil, first...) Durney
XS400 Member
Hi everyone,
It looks like I will be splitting the case once I get my 1981 XS400 home after the transmission lost it's drive. I was pulling away from a stop light and about 3rd gear, it felt like a clutch cable breaking then no drive. The cable didn't break, the motor runs fine but I can't get the gears to engage. The shift lever won't engage any gears. when pushing the bike it makes a slight ratcheting sound like a coasting 10 speed bike. No big bang or clunk just the same as if I broke a clutch cable. Has anyone experienced that before? Very strange.
Anyway, I have had this 81 XS400 for 3 years and ride it everywhere. Got it for free with 15k on it, it now has almost 25K on the clock. Last winter I replaced the rings and coated the pistons with a dry lube that you bake on in the oven. I ran great until the drive quit. Any Ideas?
Thanks,
Durney
It looks like I will be splitting the case once I get my 1981 XS400 home after the transmission lost it's drive. I was pulling away from a stop light and about 3rd gear, it felt like a clutch cable breaking then no drive. The cable didn't break, the motor runs fine but I can't get the gears to engage. The shift lever won't engage any gears. when pushing the bike it makes a slight ratcheting sound like a coasting 10 speed bike. No big bang or clunk just the same as if I broke a clutch cable. Has anyone experienced that before? Very strange.
Anyway, I have had this 81 XS400 for 3 years and ride it everywhere. Got it for free with 15k on it, it now has almost 25K on the clock. Last winter I replaced the rings and coated the pistons with a dry lube that you bake on in the oven. I ran great until the drive quit. Any Ideas?
Thanks,
Durney
I am guessing you might have the same issue I am going though. It does look like I will be splitting my case soon. Take the Drive sprocket cover off, and examine the drive sprocket. If the racheting noise your hearing is same as the feeling I had when I was moving my bike, the sprocket was still on the spindle (axle) and once I took off the cover, the sprocket came off, and the chain went limp.
http://www.xs400.com/forum/showthread.php?t=14736 my post with pics
http://www.xs400.com/forum/showthread.php?t=14736 my post with pics
Durney
XS400 Member
Thanks Tobie. Yes the same thing happened for the same reason. Reused the old star locking washer and didn't torque the nut just tightened it with a adjustable wrench. To fix it I got a new (used from Sport Wheels in Jordan MN) nut an star washer, then used lock-tite on the threads and my impact wrench to tighten the nut. Otherwise aside from some old wiring I needed to fix the bike is very dependable.
Houseman39
XS400 Enthusiast
If you are like me and are looking for the photos you can check them out here:
http://s82.photobucket.com/user/vol...w-to guides/Crankcase splitting?sort=3&page=1
http://s82.photobucket.com/user/vol...w-to guides/Crankcase splitting?sort=3&page=1
jthiessen
XS400 Addict
Hey just a quick question, will this allow access to change out second gear? I recently had a 'barn find' XS given to me. With a bit of work and a lotta love, I got it running but when i took it for a spin it makes a god awful clanking sound ONLY in second gear
Is it possible to remove gears by splitting the case like this?
Houseman39
XS400 Enthusiast
Yes that won't be too hard. Once your case is split you'll see the transmission in the middle and you can pull it straight up and out.
jthiessen
XS400 Addict
Hell yeah.
jthiessen
XS400 Addict
ALSO... When re assembling, make sure the face of both case halves are clean ( there is no gasket) .. apply a thin layer of gasket sealent on one side.. the tightening patterns and torque specs can be found in the manuals which you can download for free in the garage forum
Finally got around to this. Excellent write up, saved me so much time!
With reassembly, would it be good to lightly go over the surface with emery cloth (or something similar)?
The side cover gaskets got destroyed and I would likely need to clean the surface a bit...
Similar threads
