Rotella t4 causing clutch to drag?

[jimbocarrey]

I worked in several bike shops as a kid and it wasn't unusual for bikes to have sticking clutch plates right out of the crate. If the bikes had been boxed for an extended period of time the friction plates just stuck themselves to the metal plates. I'd just put the bikes up on their centerstand (was a thing back in the '80's) and hold the rear brake, pull in the clutch, and engage first gear. That was usually all that was required to free the plates. For severe instances where a bike had sat for years then a basket removal and a soak in alcohol would resolve the problem. I have had oils that seemed to cause this problem more than others, namely certain Bel-Ray products, but generally the issue is from the clutch not being used for a very long time. *internet photo provided
View attachment 186692

Interesting, so just rubbing alcohol? Is that the best thing to soak it in?

 

[FowVay]

Interesting, so just rubbing alcohol? Is that the best thing to soak it in?

Honestly, I don't know what would be the best thing to use. Alcohol worked for me 40 years ago but if I were to do it today I'd use a dilution of Super Clean and a maroon scotch-brite pad. Try to remove any glaze from the friction faces (possibly with fine sandpaper), soak them in engine oil overnight and reinstall them.

By removing them from the engine you can inspect them for wear and glazing and get an idea as to whether the clutch had been abused or possibly the previous owner simply didn't know how to ride. Heat will glaze the friction face but also inspect the steel plates and ensure that the little dimples are still there and they haven't been worn down.

There should be 8 friction (drive disc) and 8 steel (driven) discs. If you are replacing parts then replace the springs too.

As always, let us know what you find once you disassemble it. Pics are always a treat.

Friction disc p/n: 21441-45100 ($19 or $20 each)
Steel disc p/n: 21451-31000 ($9 or $10 each)

 

[ZeeOSix]

Ok. So I worked on the bike tonight... I don't think that spot on the shaft is actually a dot, I think it's just a discoloration from corrosion or something. I can't see any indentation when looking at it close up. Whereas the brake pedal has a clear, deep stamped indentation. I took some more better quality pics of it and of the brake pedal for compsrison.

Anyway I removed the release arm and rotated it 1 tooth further on the spline, even that made it super tight with zero play, no way you could move it 2 teeth. In short, it made no difference, the clutch is still dragging. After I rotated it I realized that just adjusting the cable accomplishes the same thing because even after rotating the release arm still moves the same amount when you pull the clutch lever, if all the slack is adjusted out of the cable.

I'm surprised there isn't an alignment mark on the actuation shaft, because the position of the arm on the shaft could make a difference in the overall actuation stroke movement depending on the position of the lever on the shaft when the cable play was correct and clutch lever is pulled. Anyway, it was worth a try.

 

[jimbocarrey]

I'm surprised there isn't an alignment mark on the actuation shaft, because the position of the arm on the shaft could make a difference in the overall actuation stroke movement depending on the position of the lever on the shaft when the cable play was correct and clutch lever is pulled. Anyway, it was worth a try.

I was surprised too, also strange that the manual didn't mention anything regarding installation of it. I guess you just rotate it as many teeth as possible when reinstalling, the angle difference from one tooth to the next is actually pretty large so it wasn't even possible to install it with the gap aligned with what looked like that dot in the videos. That position wouldve been 2 teeth away from where it was and I could only rotate it by one tooth, and even that was almost impossible...had to remove the Cotter pin from the cable and muscle it on.
But the cable only has so much travel regardless and even maxed out it the clutch was still dragging so I'm curious to see if there's anything abnormal with the clutch plates. I'll post back when I get it apart.

 

[jimbocarrey]

Honestly, I don't know what would be the best thing to use. Alcohol worked for me 40 years ago but if I were to do it today I'd use a dilution of Super Clean and a maroon scotch-brite pad. Try to remove any glaze from the friction faces (possibly with fine sandpaper), soak them in engine oil overnight and reinstall them.

By removing them from the engine you can inspect them for wear and glazing and get an idea as to whether the clutch had been abused or possibly the previous owner simply didn't know how to ride. Heat will glaze the friction face but also inspect the steel plates and ensure that the little dimples are still there and they haven't been worn down.

There should be 8 friction (drive disc) and 8 steel (driven) discs. If you are replacing parts then replace the springs too.

As always, let us know what you find once you disassemble it. Pics are always a treat.

Friction disc p/n: 21441-45100 ($19 or $20 each)
Steel disc p/n: 21451-31000 ($9 or $10 each)

View attachment 186878

Yeah I wondered about something like mineral spirits but I don't want to damage the friction plates. Not sure if something as harsh as brake cleaner would cause a problem

 

[BusyLittleShop]

After disassembly see if your local dealer will Mic them for thickness limits and check the steel plates for distortion in accordance to the shop manual...

 

[Mackelroy]

So a couple months ago I bought a 1982 Suzuki Gs750t with 18,000 miles. After riding it a bit I decided to change the oil and filter, i used a k&n filter and Rotella t4 15w-40. Right after changing it I let it idle for 5 minutes and topped off the oil level and then rode around a bit, everything seemed to be working fine. This one like 10 days ago.

The yesterday I start it up to go for a ride and now the clutch won't disengage. It just lurches forward and stalls out when you try to shift from neutral to 1st or 2nd. The cable is working and adjusted, and the lever down at the clutch is moving properly. If I turn the motor off and pull in the clutch, I can push the bike forward or backwards in 1st gear but just barely, it takes a lot of effort. So it's dragging bad but not 100%, obviously the plates aren't frozen together.

What did I do wrong here? Everyone says that rotella will work but did it swell up my clutch plates or something?

Rotella t 4 is a very strong friction oil, so wouldnt be surprised with some clutches might have some drag issues.

The answer try a less frictional oil, and see if issue subsides.