Anyone rebuilt clutch basket cush-drives?

[James P]

Yamaha workshop manuals say to replace the clutch basket cush-drive assembly if there is any play.

After further research, I have found the statement above to be only partially true. Certainly there is a picture with caption in the official Yamaha TZR 2MA workshop manual, setting down the requirements for circumferential play in the clutch basket cush-drive. However, there is no such picture or caption in the official Yamaha TZR 1KT workshop manual.
Just to make sure, I spent an hour or so translating the few short paragraphs of Japanese text adjacent to the pictures dealing with clutch basket examination. The text mainly describes wear or damage that may be encountered on the helical gear teeth and clutch plate thrust surfaces and how to deal with it - nothing about circumferential play in the cush-drive (unless I've missed something). I've also got official Yamaha workshop manuals (in Japanese) for the SDR and DT200R - any mention of circumferential play is also missing from them.

Perhaps play in the cush-drive is only a problem if you live in Europe ... . I did manage to find a spare 1KT clutch basket assembly but, for once, I'm disappointed to say that it is in excellent condition. There is absolutely zero circumferential play and only some very slight signs of use on the clutch plate thrust surfaces. For this reason, I am hesitant to dismantle it to see what is inside. If I come across one in worse condition, I will definitely pull it apart for inspection. However, that may not solve the mystery of whether play in cush-drives is allowable or not. If anyone has any additional info, please let us know!

Regards,
James

[alex_d]

Hello James,

I have a Dt200R with the similar problem, play in the transmission.
I still did not open my engine cause Im looking for the possible spare parts and localizing the issue.
But it feels like a play in the basket clutch. It rattle also a bit on idle.

Did you find all necessary info and parts ?

European DT125R is basically the same bike as the 200cc model. A lot of parts are interchangeable.

Pitty that I cant open your photobucket with pictures ..

Regards

Alex

[James P]

Yes Alex - apart from the number of teeth on the primary drive gear, the DT200R clutch basket cush-drive assembly is identical to the SDR.
I still haven't found a source of new rubber cushions, so I just took the best cushions from all of my spare clutch basket cush-drive assemblies. There is some play in the rebuilt assembly, but it isn't much (about 1.5mm maximum, from memory). I'd still be interested to find new rubber cushions if anyone comes across a possible source.

If the photos would be of any use to you, I could send them via e-mail - let me know.

Regards,
James

[alex_d]

Hi James, thanx for the reply.
Can you post please the size of old removed rubbers / cushions?
The first logical though is to look at rd250 (lc/f1-2),
they are largely available,
How did you connect back primary drive with the basket, with rivets (if yes what size),or with screws?
Regards,
Alex

[Hoatso]

Would it make sense to inject the gap around the rubbers with a 2-part rubber or elastomer? Or even a hard compound. Perhaps this could be done through a small hole or gap without disassembly of the clutch basket. You would want a compound that sets up firm and is immune to oil.

[James P]

Hi James, thanx for the reply.
Can you post please the size of old removed rubbers / cushions?
The first logical though is to look at rd250 (lc/f1-2),
they are largely available,
How did you connect back primary drive with the basket, with rivets (if yes what size),or with screws?
Regards,
Alex

There are six rubber cushions; two of them are completely round and four of them are almost-round with one flat edge (I can send you a picture via e-mail if you want). The round ones are about 22.5mm diameter and about 10.5mm thick (RD/RZ cushions are same diameter, but only about 8mm thick). You could probably use six round cushions if you wanted to, but I couldn't find any new ones of the correct size.

You can buy new rivets to reassemble the cush-drive (the rivets are the same as RD/RZ), but I reassembled mine using screws as follows:
a) Drilled three existing holes in clutch basket out to 1/4"
b) Using Recoil brand thread repair kit (similar to Helicoil), tapped the holes through and screwed in M6-2D inserts
c) Reassembled using M6x16 high-tensile button-head Allen-socket screws, secured with high-strength Loctite

Would it make sense to inject the gap around the rubbers with a 2-part rubber or elastomer? Or even a hard compound. Perhaps this could be done through a small hole or gap without disassembly of the clutch basket. You would want a compound that sets up firm and is immune to oil.

I'm not an expert on the properties of such materials, but would expect that each cushion would have to be a homogeneous mass for it to work correctly and last for any appreciable length of time. I would imagine that any added material would simply get squeezed out fairly quickly. No doubt new cushions could be moulded/cast from suitable material though.
I did think of having new cushions machined from some material, but I doubted my ability to find such a material with suitable resilience/toughness/hardness/oil-resistance/heat-resistance...and whatever other properties the material must possess for such duty.

It would be nice to find a company which is experienced in making such items and can make new ones to a customer's dimensions - I have been unsuccessful so far .
I found a couple of (presumably small) firms in USA advertising replacement cushions for the YFS200 (same as SDR & DTR), but neither of them replied to my enquiries .
Of the larger firms which supply cushions for various models, Hinson was distinctly unhelpful and I didn't even bother with Wiseco (due to similar responses in the past when making technical enquiries). Neither of these two larger firms seems to offer any replacement cushion of the correct size (for the YFS/SDR/DTR) at present.

Regards,
James

[alex_d]

Hello James,

thanx for this excellent info, please see as message my email for the pics of dampers.

Check this SDR clutch play video, did you had it same ? : https://www.youtube.com/watch?v=yTKmnAJt3Fw

He made also a custom USB programmable CDI for SDR.

He is doing some interesting research on SDR ( R-1z too).

Regards

Alex

[James P]

Alex,

I've sent you some photos by e-mail. I have seen other videos from that source you mentioned, but not the one with the clutch baskets.

The amount of play in my various clutch baskets was less than the worse of the two in the video, but was still noticeable. I also had a little play in the small kickstarter gear on all baskets, but again it was much less than the worse of the two in the video.

Regards,
James

[Jim Lyon]

Would it make sense to inject the gap around the rubbers with a 2-part rubber or elastomer? Or even a hard compound. Perhaps this could be done through a small hole or gap without disassembly of the clutch basket. You would want a compound that sets up firm and is immune to oil.

Firstly, according to Norbo's Forum some engines come with play even when brand new !
Secondly though I've never dealt with transmission play here I dealt successfully with loose cush rubbers in the rear wheel by applying it on the internal & external straights using Silcoset 151 ( you can get that in the UK from Cromwell Tools - there's now a 152 version available but I haven't used it yet ) - 151 is quite firm when it sets & I trimmed it as necessary with a blunt razor blade.
How it copes in oil I've no idea, but it seems likely it'll stick better to surfaces that are chemically clean?

[Jim Lyon]

<SNIPPED>

I found a couple of (presumably small) firms in USA advertising replacement cushions for the YFS200 (same as SDR & DTR), but neither of them replied to my enquiries .
Of the larger firms which supply cushions for various models, Hinson was distinctly unhelpful and I didn't even bother with Wiseco (due to similar responses in the past when making technical enquiries).

Yes, with this all too common attitude of being "Exceptional" I've found that many Yanks tend to be xenophobic !

[SeaR1ck]

I can try asking for this yank hates the bull shit lack of customer service u.s. companies will give towards international buyers. They tell you to contact your local distributor?