Clutch replacement - drive plates only?

[longranger44]

So the clutch in my 82 750t has begun slipping a bit, only at high rpms under full throttle. As well as dragging quite a bit when cold to the point where the bike will stall if I try to put it in gear without letting it idle for at least 5-10 minutes, depending on how cold it is outside.

I pulled it apart and mic'd the friction plates, they are all within spec. The metal drive plates however are all out of spec when checked for straightness with a feeler gauge and plate glass. So my question is, should I just replace the metal drive plates? Or should I just replace the whole kit and caboodle, friction plates, drive plates, springs, etc? Is there any consensus on what the best clutch kit to buy is? I'm having trouble finding the correct oem kit. If anyone has the part number for the oem or another good brand I'd be very grateful :biggrin:

 

[Nessism]

There are lots of opinions on this subject. Many say, use OEM parts where possible. I'm in that camp. OEM clutch springs for sure. For the steel plates, options are limited. Friction plates are more readily available aftermarket, but you need to hit ebay or similar if wanting NOS friction plates. My opinion is to stay OEM, or quality aftermarket, like EBC.

https://www.ebay.com/itm/134879307102

https://www.partshark.com/oemparts/a/suz/50d400b2f8700230d8b4e33d/clutch

 

[Grimly]

As well as replacing the clutch, drop the sump plate for a look at the oil pick-up. When the clutch has been slipping it's also been shedding fibres that block up the mesh on the pick-up.

 

[rphillips]

First off, be sure not to use newer more modern oil with friction inhibitors, nor slick additives, these old GS clutches don't like that. No doubt if you can use OEM, you won't need to wonder about the quality of an after market. I've usually just replace what is out of spec or visually something amiss, My opinion and my opinion only, if I get a new fiber plate to replace a perfectly good fiber plate, you got the same thing only newer. For me, if clutch is slipping, springs for sure, if they're not sagging a little after 43 yrs. they should be. "I" wouldn't recommend HD springs.

 

[longranger44]

First off, be sure not to use newer more modern oil with friction inhibitors, nor slick additives, these old GS clutches don't like that. No doubt if you can use OEM, you won't need to wonder about the quality of an after market. I've usually just replace what is out of spec or visually something amiss, My opinion and my opinion only, if I get a new fiber plate to replace a perfectly good fiber plate, you got the same thing only newer. For me, if clutch is slipping, springs for sure, if they're not sagging a little after 43 yrs. they should be. "I" wouldn't recommend HD springs.

I'm current using the valvoline blue bottle stuff is that not a good choice?

 

[longranger44]

As well as replacing the clutch, drop the sump plate for a look at the oil pick-up. When the clutch has been slipping it's also been shedding fibres that block up the mesh on the pick-up.

Well my friction plates are within spec and actually at the high end, but the metal plates are slightly warped so I'm assuming that's what's causing the slipping and there shouldn't be any shredded stuff in the pickup?

 

[longranger44]

There are lots of opinions on this subject. Many say, use OEM parts where possible. I'm in that camp. OEM clutch springs for sure. For the steel plates, options are limited. Friction plates are more readily available aftermarket, but you need to hit ebay or similar if wanting NOS friction plates. My opinion is to stay OEM, or quality aftermarket, like EBC.

https://www.ebay.com/itm/134879307102

https://www.partshark.com/oemparts/a/suz/50d400b2f8700230d8b4e33d/clutch

Yeah I'm finding a lot of the friction plates but no oem metal plates so I was hoping there'd be a consensus on a good aftermarket metal plate...

 

[Grimly]

Well my friction plates are within spec and actually at the high end, but the metal plates are slightly warped so I'm assuming that's what's causing the slipping and there shouldn't be any shredded stuff in the pickup?

It's 40 years old. Your choice, do you feel lucky?

 

[first timer]

I would do fibers as well as steelies. They have some age on them. It the steelies got hot enough to warp then the fiber's aren't likely very happy either. Throw the old fibers in box and horde them if you get in a pinch down the road.

No idea what's in Valvoline blue bottle, but look for a label on the bottle that sez energy conserving. It it has that label it's the wrong oil and friction modifiers were added.

 

[Nessism]

There is always a lot of banter about auto oils causing wet clutch slipping in motorcycles, but the oils that have friction modifiers, labeled Energy Conserving, are only the low viscosity oils. 40 or 50 weight oils are not affected.

 

[longranger44]

There is always a lot of banter about auto oils causing wet clutch slipping in motorcycles, but the oils that have friction modifiers, labeled Energy Conserving, are only the low viscosity oils. 40 or 50 weight oils are not affected.

Here is what I used

 

[longranger44]

I would do fibers as well as steelies. They have some age on them. It the steelies got hot enough to warp then the fiber's aren't likely very happy either. Throw the old fibers in box and horde them if you get in a pinch down the road.

No idea what's in Valvoline blue bottle, but look for a label on the bottle that sez energy conserving. It it has that label it's the wrong oil and friction modifiers were added.

 

[longranger44]

It's 40 years old. Your choice, do you feel lucky?

Doesn't hurt to check it I guess, hopefully I can find the right gasket

 

[Rob S.]

Here is what I used

It says OK for wet clutches, so that's the key. Get a good deal on it?

 

[longranger44]

It says OK for wet clutches, so that's the key. Get a good deal on it?

No paid full price, I first tried Rotella but the clutch wouldn't disengage at all even when warm so switched to this stuff because I had people saying to use motorcycle specific oil lol. I saved the Rotella so after I do the new clutch I could try that again if the people here think the valvoline isn't good for this old of a bike.

 

[first timer]

oil is oil, stick to the 10w-40 the clutch won't care if it's rotella or Valvoline blue or even off brand autoparts store house brand. I am using some walmart 10-40 dino bones stuff to break in a motor right now that gets dumped in 100 miles and my new clutch is feeling fine.

you likely have some mechanical issue that is the root of your issues, so i would pull the whole clutch apart and clean and check stuff.

 

[Rob S.]

oil is oil, stick to the 10w-40 the clutch won't care if it's rotella or Valvoline blue or even off brand autoparts store house brand.

That's the way I feel. Old 'dinosaur' for the '82 Suzuki and synthetic for the 2016 Harley. :encouragement: