81 GS750E Really hard pull clutch

[jdvorchak]

Ok this is not solved. Seems to change almost daily and maybe I just need to get it put back together and ride it. When I had the clutch cover off and I also pulled the pressure plate off to inspect the clutch plates. All looked really good to me. But I did notice that the pressure plate springs were hard to put back in. I had to apply a lot of force to compress the springs just to get the bolts started. Is that normal? I'm wondering if a PO didn't put some whiz bang performance clutch and springs in. On my Honda clutches the bolts start and usually a couple of turns in before they engage the springs. That brings up another point. I didn't count the friction and steel plates. It wouldn't really surprise me if someone had added one. But I do remember that the pressure plate was below the level of the basket so at the time I didn't think that looked strange.

As it is today I have to remove all but the slightest lever free play to disengage the clutch. Otherwise the bike will creep on me and rpm goes down if I put it in gear from a stop.

[hillsy]

Sounds like the PO might have put some heavy duty springs in there - which will explain the heavy lever.

My 1150 used to have a bit of clutch drag. I just lived with it, but in hindsight it was probably slightly warped steel clutch plates.

[Lorenzo]

Sorry to hear the problem ain`t solved yet;
before delving into springs and pressur plates, are you aware of the implications of the incorrect thickess of the cover gasket?

[jdvorchak]

Sorry to hear the problem ain`t solved yet;
before delving into springs and pressur plates, are you aware of the implications of the incorrect thickess of the cover gasket?

First I've heard of it. I have a new cover gasket on there but it's not OEM. Aftermarket gasket. Please elaborate.

[Lorenzo]

Having had a similar problem i.e. gears not engaging, after a full gaskets replacement, I did a bit of scavenging in the old forum threads and out it came that a dissimilar gasket or, as in my case, an RTV seal, -being given the wrong one- can lead to this situation, and them were right!
Since you got two, try both `em on, or put the old one back if still useable.
After all, shifting was fine before you "disturbed" the plot...

[jdvorchak]

Thank you Lorenzo but my problem is not related to gear engagement. And I just bought the bike and replaced the clutch cable at the same time that I replaced the gaskets. The original gasket was broken and the PO had used RTV to seal it. I never rode the bike prior to changing gaskets so I have no baseline from which to judge.

[Nessism]

The 1000S clutch cable is a good match when using Superbike bars. The shorter length means easier to route and smoother pull. OEM cables are superior to aftermarket too.

I'd order up the proper cable and a new set of stock springs. Could be that someone ordered up some Barnett spings or similar. Also count the plates and compare against the fishe. Some guys went to aftermarket clutches with thin plates which damage and tear up the clutch basket. You better check for notches while the clutch is apart since notches tend to hang up the plates from sliding easily.

[jdvorchak]

Thanks Ed. I'll get into the clutch tomorrow if I have time. I really suspect that someone put in gs850 springs, which are longer. But as your sig says "to measure is to know". In any event I've had enough old UJM to know something is not right. The clutch cover is easy enough to pull so no point in guessing anymore. I rode it about 4 miles today and other than the clutch pull it runs amazingly well. Smooth, tons of torque and when it hits 5k rpm, hang on!

I also have a KZ1100 with the clutch slipping. I guess it's clutch week.

[jdvorchak]

I completely disassembled the clutch today and I can't find a thing wrong. Everything under the clutch cover looks and measures like new. All specs on clutch plates were well above the service limit. Thickness, ears everything. Steels still had peen marks from the factory. I checked my records and the clutch cable I put on was NOS original Suzuki part from a GS1000. I'm at a loss. I'll try riding the bike more and see if it loosens up a bit from use. It's been a long time since oil was splashed around in there and remember it did have a lot of water in the oil when I bought it. When I reassembled the clutch I hosed it down pretty good with motorcycle oil and at least today it feels easier and smoother. So far it has not been reliable for me to take it on long enough trips to fully warm the engine and trans but I have that problem solved. The pulse gens had a flaky wire connection to the 2-3 pulse gen. Looked like the break in the wire was just as it enters the plastic housing for the pulse gen. I replaced it with a used one from eBay and it checks rock solid.

I guess this will remain one of life little mysteries. Well assuming it does get easier to pull the more I ride it.

[hillsy]

Did you measure the clutch spring free length? Someone might have put heavy duty springs in there.

Also, it might be an idea to soak the friction plates in oil overnight - if they have been dry for a while they can misbehave.

[jdvorchak]

Yes I measured the free length. Problem is I don't know what new is. The FSM has 1.52 inch for service limit but no new spec. These were 1.6 inch. All of the clutch plates were wet. I rode it about 4 miles today and had to adjust the free play twice and I'm right at the ends of the lever and clutch actuator adjustments. I'll have to pull the tank and do that adjustment in the middle of the cable. I guess the pull is so hard the NOS cable is stretching on me. No signs of wear on the cable. Just riding it around the neighborhood so while I only rode 4 miles it took me about 25 minutes so the engine came up to temp nicely. I even took off from a stop in 3rd gear a couple of times to make sure I heated up the clutch. FYI it accelerates nicely in 3rd from a stop. This thing has tons of low end torque.

[hillsy]

More likely the cable sheathing is compressing than the actual cable. Probably just "settling down".

You probably have HD clutch springs in there - they may not be any longer than normal ones but the springs will be thicker with less coils.

[jdvorchak]

I'm inclined to agree with you Hillsy. I've tried everything else. I do have one more test that I can do. I also own an 83 KZ1100 that needs new clutch springs. When I swap them out for new I can try the old KZ springs in the GS and see if it's easier to pull. Since the size is roughly the same as with the KZ I can drop them in real quick and see if it helps. If it is easier those springs will probably cause the GS to slip but at least then I'll know the problem is with the springs. Oh I don't know. Maybe I should just buy new OEM springs.

[jdvorchak]

Finally got to the bottom of the clutch pull problem. After completely disassembling the clutch and measuring everything I could find I decided the new OEM clutch cable I had was bad. The way I found out was to remove the normal routing and ran the cable straight from the clutch arm to the lever as straight as I could. Pull was easier but still too hard to ride. Then I just moved the cable onto the top of the valve cover and the clutch became impossible to pull with just one hand. I ordered an aftermarket cable, that said it was nylon lined, and installed it with the normal routing. Like magic the clutch is easy to pull like a normal clutch should be.

I've had good luck with aftermarket cables and actually this is the first time I've bought OEM. Not saying OEM is no good. This NOS OEM cable I bought was not working for me.

[roeme]

Yeah, technology has progressed even for bowden cables