Almost Ready MK3, Now I'm Scared: Layshaft

Status
Not open for further replies.
I'd try heating up the case outside the layshaft bearing and see if it will just pull out, with the bearing. As I remember that's what Mick did in the DVD. My layshaft just came out of the bearing, I had to heat the case and even use a puller I made up to get the stupid bearing out. My bearing went in the case a bit hard too, but the shaft went in fine. But I used Mick's ball.

Dave
69S
 
FWIW A tight bear in the casing is a good thing, unless glued in there, and is indicative of the integrity of the machined surfaces.

Keep things square and plumb as you work this bear out to preserve these surfases.
 
jaydee75 said:
Now the inner cover is off and the only problem I see is the mainshaft bearing feels like it is a fine rachet. Seems to be notchy as I turn it with my finger.
Should I replace it? I am surprised, this thing has been ridden gently for 14k and I don't see why it wouldn't be smooth.
Click to expand...

Yes. And while you're in there, what does the large countershaft ball bearing (drive side end) feel like? You might as well go through the 'box with a fine tooth comb while you have it apart. Otherwise you might have to do another premature strip down later. Check the teeth on all the gears , the bush in 1st gear layshaft, the bush in the kickstart shaft, which supports the layshaft, and the bushes in the sleeve gear (4th gear mainshaft). Refer to Old Britts Technical Articles.
 
I'd replace all the bearings, no matter what you think. The loose bushings too, and if you want the tight bushings, but they will need reaming to fit. Replace anything that doesn't look or feel right. I had a burned shifter fork at 13K miles.

Dave
69S
 
jaydee75 said:
Now the layshaft is staring me in the face. It wiggles a little but won't budge. Can I rig up a puller to grab a gear and pull it out?
What's next?
Click to expand...

Just follow the instructions in the workshop companion.
http://www.doov.com/apps/nortoncompanio ... s&Itemid=8

Layshaft 1st & 2nd gears should come out easily after the selector shaft has been removed. The layshaft, with 3rd & 4th gears is held by the fit of the bearing so heat the case until the layshaft comes out, hopefully with the bearing on it.

The bearing puller shown in the workshop companion isn't entirely necessary, as the bearing should come off using two thin levers inserted between the bearing and gear 180 degrees apart to pry the bearing off.

Use the layshaft as the fitting tool to install the new bearing. The case needs to be hot enough so that the bearing goes in without using any force to push it home.
 
Ok I've got all the easy gears out. There are still two gears on the layshaft, I guess they both stay until layshaft removal, right?
Here's a pic:
Next step is heating and pulling?
Thanks,
JD

Almost Ready MK3, Now I'm Scared: Layshaft
 
I'd get all that oil out of there first. Then heat the dickens out of it. I had my trans out, put it in a gas grill and I still had to pull it. Hopefully yours comes out like the link from Les. In Mick's DVD, he just pulls the layshaft out with the bearing on the end. Get it hot enough when you spit on it, the water immediately evaporates. I think it would be best if you can heat it from outside the case, on the left, that way you're not heating the gears too. They're going to be hot anyhow.

Dave
69S
 
Should we assume that the primary is not disassembled? This of course will make it hard to get heat to the back side of the bearing. This will also null the replacement of th LH mainshaft bearing.

Proceeding, you can get a propane tip in there but as Dogt states, you better clean up that oil first.
 
update on my schenanigans, impact gun yawned while easily taking off the main shaft nut. no 1 1/2 sockets deep enough to get the sprocket off, and i'm surprised to say since we have 3 mechanics tools in our shop, no 1 1/2 wrenchs :shock: this bike had 22k miles on it when put away in 91, the flat head screw holding the lock washer on that sprocket side was all chewed up though, looks like someone had it off before, which makes me wonder if my dad ever had any service done to the trans! guess there is only one way to find out...
 
I am getting ready to heat it up and pull the shaft.
I'm wondering, if the layshaft bearing doesn't come out with the shaft, is there room behind the bearing to rig a puller onto.
In other words is there any kind of shoulder or something I can grab and pull it out?
Thanks,
Jd
 
jaydee75 said:
I am getting ready to heat it up and pull the shaft.
I'm wondering, if the layshaft bearing doesn't come out with the shaft, is there room behind the bearing to rig a puller onto.
In other words is there any kind of shoulder or something I can grab and pull it out?
Thanks,
Jd
Click to expand...
Yes, a blind bearing puller will get in there. Autozone may loan a set.
 
jaydee75 said:
I'm wondering, if the layshaft bearing doesn't come out with the shaft, is there room behind the bearing to rig a puller onto.
In other words is there any kind of shoulder or something I can grab and pull it out?
Click to expand...

If the layshaft won't pull out of the bearing cold, then there's nothing much to worry about.

Simply heat the case and the bearing will come out on the end of the layshaft.
 
I've got the big hollow socket to get the sprocket nut off if you want to borrow it. It is like a double socket where you use a Tommy bar on the opposite end.

Russ
 
On one of the few shells I dealt it one took like 450'F to bop out on wood block. On the reverse I once was too chicken to heat over 250-300'F to install and had the bearing get stuck mid way in crooked. That's when I lost my pensiveness to heat to oil smoking frying temps to get it out. If yours takes less the a few hundred degree's to bop about right out be pensive of bores wearing out. Thermal expansion takes a bit of time to fully creep open at least a minute at full temp on shell size item. I keep my bearing in a frozen 0'F beer coozy till ready to install, just in case I flub up and delay too much for another hang up > I hate like the dickens. On the other extreme had one shell the bearing fall straight out stone cold ugh. Hehe at first I thought I'd just not seated it fully some how so gave it one last whack just to make damn sure, and blasted it straight through and out the other side. It was informative to see how thin the shell is backing the bore up and how much the bore corners are good stress rises to focus fracture so cleanly circular, so beware there.
 
All apart except for that sprocket (may take you up on that socket russ, i'll PM you) the good news and bad news is everything looks peachy in there. Can hardly find any wear on anything...thinking this was gone over at some point in time, which makes me mad i took it apart! but it was the only way to know. still going to replace the bearings thought to be safe
 
SUCCESS! Thanks guys.
I split a piece of 3/4" aluminum conduit and used the halves as a pad for vice grips on the end of the layshaft. Then I made a hook that would allow me to
grab the vice grips with a slide hammer. I used a propane torch to heat up the inside of housing all around the bearing seat. I estimate it was right at spit
boiling when I gave it two jerks and out it came. What a pretty sight. I was afraid it might leave the bearing behind, but it all came out.
The bearing looks and feels great, but it does have the steel cage and Portugal, so I will replace it with the new polyamide version.
Anyone want to buy a good used bearing?
Here's some pics:
JD


Almost Ready MK3, Now I'm Scared: Layshaft


Almost Ready MK3, Now I'm Scared: Layshaft


Almost Ready MK3, Now I'm Scared: Layshaft
 
I like the slide hammer/vice/hook setup. Creative. Very satisfying when that shaft and gear comes out, isn't it?
 
Boy, I'm glad it worked for you. When mine came out without the bearing, it took me another 2 days to make a puller and get it out. I hoped wasn't going to jinx you or anything. Glad it's working out. That means it should go back in easy. Hemmings just grabbed it with a rag and pushed it in with the layshaft. But cool off that bearing and heat the case again.

Dave
69S
 
If you're going to go with the Hemming's recommended ball (I did), remember it can't take a lot of heat (removing it like you & I did for the old one will destroy it).

So for reinstall, after getting the new bearing on the shaft, I put the whole shaft/bearing assembly in the freezer, then heated up the case to 250F. The assembly then slipped into place easily. I began to shoot some oil up in there around the back to help cool the case (just in case any hot spot wanted to migrate to the bearing shell). I think this was overkill, but ....
 
Hehe, if your bearing is at risk of loosing its temper under 400'F then better not use that one in the first place. We all are relieved to see the whole shabang come out. Ball or roller not a big difference in service as long as not defective form the get go. Balls are preferred in applications the rpms/loads cause shaft to deflect from straight so ball can take up more of that before binding loads into race and case. Same thing on TS crank old school racers like balls but current crop mostly rollers. Rollers can take more load and last longer is main reason given for them over balls.
 
Status
Not open for further replies.

Similar threads

J
  • Locked
Almost ready 74 850 boyer problem
Replies
4
Views
1,230
concours
concours
B
  • Locked
Mrs. Robinson is almost ready !!!!!
Replies
2
Views
1,052
Blkbird
B
Back
Top