I bought a 1990 GS500E about 3 weeks ago, and I'm trying to get it in reliable riding shape, as well as get good enough to pass the slow speed riding test at DMV.  The bike was dumped by its former owner, so it's not a thing of beauty, but it's nice to have a bike again.

I have been doing the slow speed practice by slipping the clutch with some rear brake, like all the sites say, but I think I may have done harm to the clutch.  Coming home this evening, the clutch started slipping.  I adjusted the cable to make sure it had enough slack, but it's still slipping.

I've searched the message boards, and it looks like I should probably do the clutch adjustment, and if that doesn't help, buy a set of clutch disks (OEM, aftermarket, or SV650) and replace them.  Is that about right? 

(I'm running motorcycle oil I bought at dealership, so I think no friction control issues with the oil).

Thanks,

Ben

Check the adjustment of the clutch pushrod cam under the little tab on the front sprocket guard.

Removing the tab you should see a slotted screw and a jam nut.  This operates the clutch pushrod which goes though the engine case and releases the clutch.  If the slotted screw is too tight, it can hold the clutch partially disengaged.

Basically, loosen the locknut and turn the adjuster out several turns.  Then turn the adjuster in slowly until you just feel resistance, then back it off 1/4 to 1/2 a turn and tighten the locknut. 

Recheck your clutch lever freeplay and try that.   

Slipping clutch could be worn clutch pads, a stuck clutch lever/cable, clutch springs gone...

OR!

bad oil, never use fully synthetic oil in a gs because it'll slip like crazy, mineral oil slips pretty bad too. I use semi-synthetic and dont have a problem.

Maybe even an oil change will solve the problem, i know of numerous other bikes this has worked on.

Quote from: metalforever on July 13, 2008, 02:38:14 AM
bad oil, never use fully synthetic oil in a gs because it'll slip like crazy, mineral oil slips pretty bad too. I use semi-synthetic and dont have a problem

Did someone mention the "O word"?  Here we go again..... remember this lad is a noob so cut him some slack 

Ok so im confused, saying oil is bad here?

Explain that one

put in synthetic oil...i find that helps. i can tell when my oil is running low when my shifting get hard and neutral harder to find.  10-40 is what i use

So mineral oil causes clutch slip and synthetic causes clutch slip, yet semi-synth which is a combination of the two doesnt cause clutch slip..........

Its not the oil itself that causes slip.....its the additives within the oil that can cause it. Mineral, synth, semi-synth, whatever you choose to use doesnt matter, what matters is that the oil does not contain the friction modifiers that make it unsuitable for use in bikes with wet-clutches.

I beg to differ mate! And not just because im stubborn.

The composition of the mineral compounds actually acts together with the man made substances to react to reduce lubrication under pressure, it's hard to explain to be honest, but yes the purer the oil, the increased likelyhood slip will occur.

As well as this, you'll find fully synth burns, and mineral can damage your engine, because to be fair, what is pure mineral oil? The word's a clue.

Thats a new one one me mate, especially when you consider that the GS engine dates back to times way before synth and semi-synth was as commonplace as it is today and was originally designed to run on mineral oil.........A question, if it is so harmful why isnt everyone who uses mineral or synth in their GS`s (like our FrankieG) suffering from slipping clutches and terminal engine damage?

I was putting JASO approved mineral oil in wet clutch bikes almost 10 years before you were born and have been using it in my GS for the last 8 and never had a problem so please understand my sceptisicm.....Unless you have got something to back your claims up I am going to assume its a wind-up......and a pi**-poor one at that.

Wey perhaps im getting mixed up with more modern engines as i must admit your right the engine was designed to work with mineral oil, infact leaded fuel also!

But i do believe newer models benefit from semi-synth, i know my clutch slipepd alot with fully synth in until i changed that.

Here's a link to a break down of what I did to upgrade my clutch.  http://gstwins.com/gsboard/index.php?topic=42447.0 Half way down the page is my post on my clutch.

I would try an oil change.Use 10-40 oil.Make sure the oil doesn't say energy conservation or friction modifiers on the back, in fine print.This is the problem with oils.Friction modifiers cause the clutch to slip.

Quote from: metalforever on July 13, 2008, 12:30:15 PM
But i do believe newer models benefit from semi-synth, i know my clutch slipepd alot with fully synth in until i changed that.

Was the oil you used suitable for use with wet-clutches?

Not a clue, it was from the previous owner!

So it could have been filled with synthetic oil intended for use in cars and not suitable for use in bikes with with wet clutches?

>> (I'm running motorcycle oil I bought at dealership, so I think no friction control issues with the oil).

I had seen all the oil posts when I did the forum search on the clutch topic so I included the info above in my original post.

I changed the oil with Suzuki 10-40 that I bought at the dealership 2 weeks ago.  I didn't think to look, but I don't think it was synthetic.

As for my riding, I have been slipping the clutch a lot and working on slow-speed stuff.  After a few minutes of this, the clutch friction point seemed to change, and I had to adjust the clutch cable to compensate.  I did this adjustment about every other time I would practice the slow stuff with all the clutch feathering.

Doing this 8 times or so over the last 2 weeks brought me to the point where the clutch would start to slip at highway speeds.  I can baby it and make progress, but I can't use more than 1/5 throttle without clutch slip.

So, back to my original question, assuming it isn't the oil, I plan to try the clutch adjustment as described by GeeP and if that doesn't help, buy a set of clutch disks [OEM, aftermarket, or SV650 (as described by ben2go)] and install.  During clutch replacement, if I find out-of-spec or warped steel disks or wimpy springs, I will replace those.

Does that sound like a good plan of attack?

Thanks,

Ben

Best thing you can do is buy a copy of the Haynes manual, the clutch adjustment and replacement procedures are covered in detail.......dont forget to order a crankcase gasket, there are no guarantees the old one will survive when you pull the cover off.

 
Good news...I did the adjustment procedure per GeeP's instructions, and the clutch seems to be well behaved now.  I'll wait on the replacement until it's required!

Thanks, all for the advice.

Ben

Cooooool!  Every now and then you need to get in there and readjust things.   

Wet clutches are like bulldozer steering clutches.  You really need to TRY to kill them to cause damage.