Clutch Basket Replacement

[hudtm60]

Fingers are looking a bit iffy, and there’s a bit more rotation than your average LC should have but I’m ever wary about going in and ruthlessly defiling an original genuine Yamaha component- in this case drilling out the rivets.

Thankfully Dusty documented his replacement procedure in his rebuild threads (excellent) so it’s not too much of a mystery and I should be able to manage it, but can’t make me mind up.

[spooch63]

You've already shelled out for the replacement parts, centre punch the rivits to keep your drill bit centred. If your nervous about the actual drilling I'd get a new drill quality drill bit just to make sure it's capable of drilling cleanly, use a pillar drill not a hand held. Failing that you could always ask Muttsnutts to do it for you.

[hudtm60]

Cheers spooch63. I think you're right, I should bite the bullet and dive in. I've got a pillar drill that might be up to it. Only issue is that orange gasket, or the predicted lack of. I reached out to the chap "Rolie" who was making them (or getting them made) that Dusty connected with and got a couple from but not heard back from him yet- not holding my breath...last time he was on...Nov '22. 

[dusty350]

I think I got the last 2 from Rolie. Wasn't Rob thinking of doing them ? There was a fairly recent discussion on here about them, with the material they are made from (Mylar if I remember correctly ?) being the main discussion point I think. BDK list them now, but I dont know what they are like as not seen one. You may find your original gasket intact once you strip the basket - I've certainly found a couple that can happily be reused when I've stripped them, but others are virtually non existent. There are a couple of different designs - later gaskets on the last Pv's are virtually a round sheet with just 4 cut outs for the cast posts, so a lot more material and less likely to tear. And dont fret about the rivets - as Spooch said, centre punch them and start with a smaller pilot drill to centre the hole, then you can always go up in size rather than just going for it straight off ! Some guys just grind the heads off but I prefer to drill (pillar drill). And buy good quality rubber pucks - they are the parts that will be doing the work ! I got my last set from Mutts - I've used Wiseco in the past but they are very expensive now. I wouldn't buy from Shambits !
It's always been a popular topic regards the amount of rotational play between the basket and driven gear on the back. Some say up to 5mm is ok, anything more is excessive. Yamaha never sold the gaskets or pucks separately as they never designed the clutch to be serviceable beyond the plates and springs, but as we know, 40 odd years later they often need some tlc. Gaskets do disintegrate, and pucks do break up;

352519235_139888525766857_1747768457921468203_n by dusty miller, on Flickr

The gasket will help prevent wear due to the rotational movement between the alloy basket and steel gear, so paper wont do. The original is a plasticky type material. I think Rolie did a fair bit of research to come up with his version;

20220929_201327 by dusty miller, on Flickr

Good luck, take your time, it's an easy job with the right tools

[dusty350]

And, just to add, an early Yamaha Lc gasket;

20170217_175256 by dusty miller, on Flickr

And a Yamaha gasket from a 2UA Pv;

20190526_214221 by dusty miller, on Flickr

You can see the last of the Pv's had a lot more material in the gasket, and the pucks will sit on top of it. It would be a lot easier/cheaper to copy the last version I guess ?

Dusty

[hudtm60]

Cheers Dusty. 

Very much appreciate the feedback! I have to also say (probably not for the first time) that I wouldn't have even been close to ever being able to rebuild these engines without your two rebuild threads. I've also tried to emulate them and document as much as possible for my own use, but it's funny how in the excitement in piecing something together like the tacho drive, you forget to take one pic! Props to you for the discipline in being so thorough and helping so many of us. 

Also thanks for the tip about BDK. Even if the gasket is good I think I'll order and install one- although if I could get the correct material it looks like copying the 2UA PV style would be fairly easy AND more effective. I'll think about that. 

I was tempted to order some Wiseco rubber bobbins but, yeah, pricey...so I'm sticking with the ones that came with the basket I got from Norbo. I trust they'll be fine. Truth is, they won't get the same hammering day in day out the way we used to ride. Well- there will be the hammering but it won't be every day like it was in the '80's. 

[muttsnuts]

Dusty, Rob has made a prototype which I've fitted to a clutch and its all good, the only thing I haven't done yet is test it in anger, but from what I've seen I reckon it will all be good, so hudtm60 contact Rob on here and see if he will sort you one out

HTH

[Tobyjugs]

I can't really see the make of clutch basket used.
One make of clutch basket (Hinson maybe) quotes not to use the gasket.
Check to see if you need one with the manufacturer.

[dusty350]

Cheers Dave,
I thought it was Rob who had talked about doing it. I would certainly buy a couple for future rebuilds


Dusty

[stusco]

Dec 29, 2023 3:23:46 GMT 1 Tobyjugs said:

I can't really see the make of clutch basket used.
One make of clutch basket (Hinson maybe) quotes not to use the gasket.
Check to see if you need one with the manufacturer.

Looks like chariot on the basket

[4l04ever]

These are the test ones I made. I could make YPVS ones too if required. I would need to take a YPVS one apart and make some measurements as the pucks may be slightly thinner to allow for the gasket being underneath them.



This is an equivalent of Mylar-A, as that is not available from my supplier.

The material is called PMX500. It is classed as a polyester film.

I will put some offcuts in my gearbox oil to see if it gets affected.

Info from supplier :-

Excellent mechanical strength and dimensional stability
Does not become brittle with age under normal conditions
Good resistance to moisture and most chemicals
Can withstand temperatures of -70C to +150C

[Robbieben]

Dec 29, 2023 11:51:17 GMT 1 4l04ever said:

These are the test ones I made. I could make YPVS ones too if required. I would need to take a YPVS one apart and make some measurements as the pucks may be slightly thinner to allow for the gasket being underneath them.



This is an equivalent of Mylar-A, as that is not available from my supplier.

The material is called PMX500. It is classed as a polyester film.

I will put some offcuts in my gearbox oil to see if it gets affected.

Info from supplier :-

Excellent mechanical strength and dimensional stability
Does not become brittle with age under normal conditions
Good resistance to moisture and most chemicals
Can withstand temperatures of -70C to +150C

Rob I'd happily take a couple of PV Gaskets if you are making some.

I'm also looking for a steel backplate for my 31k if anyone has a spare one kicking about they'd be willing to part with. The round one that is usually riveted in holding the gasket and rubber pucks.

[dusty350]

Great work Rob

[beardy]

For those that have used rivets to reassemble the clutch basket. If you used a press, how much pressure is required to deform the rivets?
I’m asking as I guess it would be all too easy to over tighten them?

[stusco]

I used a ballpeen hammer the first time it’s really a two man job, i have one of those chariot jobs now i got it from mutts easy to fit but had to swap out the springs as they were too heavy for me

[muttsnuts]

Dec 29, 2023 11:51:17 GMT 1 4l04ever said:

These are the test ones I made. I could make YPVS ones too if required. I would need to take a YPVS one apart and make some measurements as the pucks may be slightly thinner to allow for the gasket being underneath them.



This is an equivalent of Mylar-A, as that is not available from my supplier.

The material is called PMX500. It is classed as a polyester film.

I will put some offcuts in my gearbox oil to see if it gets affected.

Info from supplier :-

Excellent mechanical strength and dimensional stability
Does not become brittle with age under normal conditions
Good resistance to moisture and most chemicals
Can withstand temperatures of -70C to +150C

Rob, I've got a complete YPVS one in the workshop, I can post you it if you want to copy, the clutch puks are all the same in ticjkness, just the diameters differ between certain clutches

[4l04ever]

Can you check the thickness of the YPVS one? Is it 0.5mm? If you post one to me, I can draw it up on CAD.

[hudtm60]

Finally got a chance to dismantle the clutch basket. Like all said fairly easy- good to follow Dusty’s thread

Replacement basket is from Norbo. Chariot.

Found the original gasket still exists at lot better than one of Dusty’s but it’s torn in spots. Putting it in place on the new basket and then taking it off and on and you can tell the difference.

Seems to me that a gasket is a necessity- it just feels better with one in place rather than metal to metal but let’s face it, with new rubbers in and probably not chalking up that many miles per year it probably wouldn’t be an issue in putting the old one in but Rob, will you sell me one of yours? Either LC or YPVS? I’ve reached out to Chariot to see if they recommend one but I bet they will say no. I’d rather have one.

[hudtm60]

FYI I popped along to Nashville Rubber and Gasket and they said they could whip up one for me by tomorrow. Getting two just in case. Will report back with pictures. Happy to get more done if they're reasonably priced.