Time for a new clutch

[93Bandit]

Yeah time for new fibres. They look glazed and being a cheap bastard id sand them and maybe shim the springs.
doubt its worth the effort though.

I agree, probably best to get new frictions. Not only would sanding probably bring them below spec, but I also fear they'll start coming apart. As I mentioned before the material is quite brittle and was coming apart as I clean the plates off. Im a tightwad as well and like to save where I can, but I'll admit I end up going through more frustration and expense trying to save a buck sometimes. Occasionally it's worth spending the money upfront to avoid the hassle and other potential issues.

[93Bandit]

For me, clutch plates at, or below, factory spec., does not mean the clutch is already slipping as this one was. The factory spec. tells you it's time to maybe replace so it doesn't start slipping.....Telling you problems are getting near. Kind'f like the factory spec. for brake rotors, they tell you the rotors are nearing the time they may (could) cause a problem. Would be no reason for the min. spec. if the item had already failed when it got to min. spec. Plus they will always give themselves a little wiggle room for safety and for selling more replacements.

I agree with what you're saying. The only caveat with factory specifications is they cannot always capture all possible variables. In this case the measured thickness is within the acceptable range, but what cannot be easily measured is other ways the material has degraded due to time and heat cycles etc. Being the material is glazed, brittle and near the end of acceptable thickness, I think replacement is probably the right course of action. Especially considering I've already addressed all other possible causes of a slipping clutch. This is all there is left to do.

[Blue_magician]

How similar are the clutches on the 1978 gs1000 to your clutch? I’m finding two different types of friction plates on mine. I believe it’s the original.

[93Bandit]

How similar are the clutches on the 1978 gs1000 to your clutch? I’m finding two different types of friction plates on mine. I believe it’s the original.

I have no idea. I don't have a 1978 GS1000 to compare to.

[Cipher]

I agree with what you're saying. The only caveat with factory specifications is they cannot always capture all possible variables. In this case the measured thickness is within the acceptable range, but what cannot be easily measured is other ways the material has degraded due to time and heat cycles etc. Being the material is glazed, brittle and near the end of acceptable thickness, I think replacement is probably the right course of action. Especially considering I've already addressed all other possible causes of a slipping clutch. This is all there is left to do.

Aging of the material might also manifest in shrinkage and compaction. And 40plus years must impact the adhesive.

[Cipher]

How similar are the clutches on the 1978 gs1000 to your clutch? I’m finding two different types of friction plates on mine. I believe it’s the original.

21441-49002

is the part number. Fiche shows only one number for all but the latest number supersedes #s 21441-49000
and 21441-49001 which may look different but obviously still fit.

[rphillips]

No way to never argue about changing any normal wear items that are 40 yr. old.

[93Bandit]

I fitted EBC in 2019, with no trouble. The old plates were ancient and glazed, but had hardly any wear in them. I also fitted three slightly heavier springs and three OEM springs. All is peachy now.

What oil are you using with your EBC clutch? I was reading the Q&A on EBC frictions and they specify NOT to use synthetic oil with the plates unless it is motorcycle specific. I've been using Rotella T4 which I believe is a synthetic blend. Will I be able to continue using this oil with EBC?

[Rich82GS750TZ]

Rotella T4 meets JASO MA/MA 2 spec.

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[Grimly]

What oil are you using with your EBC clutch? I was reading the Q&A on EBC frictions and they specify NOT to use synthetic oil with the plates unless it is motorcycle specific. I've been using Rotella T4 which I believe is a synthetic blend. Will I be able to continue using this oil with EBC?

I've been using semi and full synth for the past decade. Mostly car and diesel oil, with only a couple changes using bike-specific oil, when it was priced right.
Currently using Mannol 10w40 car and diesel synth, which has a Jaso MA rating also.

[93Bandit]

Rotella T4 meets JASO MA/MA 2 spec.

Right, I knew that but the comments from the seller of EBC clutches threw me off. Thanks for the reassurance.

[93Bandit]

I've been using semi and full synth for the past decade. Mostly car and diesel oil, with only a couple changes using bike-specific oil, when it was priced right.
Currently using Mannol 10w40 car and diesel synth, which has a Jaso MA rating also.

Thanks for the reassurance. I'll get those clutch discs on order ASAP. I'm missing out on some great riding weather!

[joequesmith]

OEM clutch plates are very expensive, so searching the GSR I see mention of EBC plates being just as good as OEM and cheaper. I plan to get EBC friction plates, but my question is whether or not I should replace the steel plates as well?

The only time I have replaced the steel plates is when they warp. I pull the pack, clean the steels and squeeze them all together with my hands. When I hold them up to the light, if I see any gaps then I replace the bad ones. I wouldn't think you would ever see something like this.

Brand wise, I tried a few different ones but pretty much stuck with OEM.

[rphillips]

Always heard lay plates on a sheet of glass, to check for warpage, I guess glass is always supposed to be flat.

[93Bandit]

Always heard lay plates on a sheet of glass, to check for warpage, I guess glass is always supposed to be flat.

That's what the factory manual says to do. I've seen glass with waves so I thought it was interesting they specify a pane of glass. I didn't bother, I held them together like what was previously suggested and didn't see anything obvious.

I tightened the hub nut yesterday, and ordered clutch frictions. The EBCs were out of stock everywhere I looked, but lucked out and found 1 set on ebay and ordered it. $69 with free shipping so that's a fair price compared to OEM. Hopefully they will solve my clutch issue.