Changing the Clutch Springs on my 1982 GS850

[legaleli]

I knew this was a reality - but it might be more than I thought:

Over the past few weeks I discovered clutch slippage on hard acceleration that began around 6 or 7 thousand rpm. At the same time I discovered the bevel gear shaft problem that I have fixed.

I ordered new clutch springs and 2 gaskets (because I'm not good with gaskets) from Bike Bandit and they should be here before this weekend arrives.

I have two questions... related but significantly different:

#1 - Is there a good thread that I'm missing showing me how to change out the springs? The shop manual is not great on this and I'd rather not "follow my nose". There are mentions of "special tools" - I don't have any...

#2 - I was out for a spin yesterday - and I was driving the bike aggressively - well... for me anyway. I shifted while cornering from 1st to 2nd and... well... the clutch slipped WAY lower than normal (around 3k I think - though I'm not sure because I was not looking at the tach). I do not feel it was cable (or driver) related - here is why:

AFTER coming out of the turn I was accelerating and I heard a "chipping" noise from the clutch/engine - it was not loud, but it chipped faster as the rpms went up, and lower as they went down, and it definitely had a "connected to the crankshaft in some way or another" sound. It sounded as if something was scraping - the noise went away after 5 or 10 seconds and the bike sounded fine after that - but I rode my bike home and quite gingerly.

I have recently read threads here about clutch baskets and bolts scraping things so I might just be getting paranoid - or...

In any event, the clutch IS coming apart for inspection and I need some H-E-L-P!

 

[mike_of_bbg]

I can't recall any particular thread about changing clutch springs, but here are some thoughts on the subject:

First, have a nice piece of cardboard around to draw the clutch cover and stick the bolts through as you remove them. They're a few different lengths and you'll want to get them back in their proper places. On my 82 GS550L (and apparently all GS550s) you can remove the clutch cover with the bike on the side stand and not lose any oil - never have heard if that's true of an 850 as well. If it's time for an oil change you might as well drain anyway.

Make sure you're not getting gas contamination in your oil, as that could cause slippage for sure.

Changing just the clutch springs is easy. Leave the bike in gear. With the clutch cover off you'll see six bolts on the pressure disk facing you; those are holding the springs. One at a time remove them, replace the spring, and tighten to torque spec. If you want to examine your clutch fibers and steels, you'll have to remove all six of the bolts and pull the pressure disk. Then you can also check the clutch hub nut underneath and be certain it's tight. Up to this point you shouldn't need any special tools.

I also found it helpful to stuff little wads of shop towel in my socket when re-installing the clutch springs so the bolts wouldn't "sink" into the socket.

Here's some pics of clutch repair from BassCliff's site:

http://members.dslextreme.com/users/storagecliff/images/clutch_odds-n-ends.html

Good luck to ya.

 

[bonanzadave]

Here's some pics of clutch repair from BassCliff's site:

http://members.dslextreme.com/users/storagecliff/images/clutch_odds-n-ends.html

Those are some basic pictures from when I changed my Clutch pack. Even tho most will relate to your 850 I think you should shoot a whole photo album and submit that to Cliff as a specific 850 clutch inspection. It really is not that hard. Mike has already posted some helpful hints and Im sure you will get more.....

Do your work on the side stand. You wont lose any oil.

Caliper to check the fibers and steels tolerance. A cheap one will be fine.

An impact wrench for the Hub nut. Kinda pricey. My auto store rents them.

 

[legaleli]

Those are some basic pictures from when I changed my Clutch pack. Even tho most will relate to your 850 I think you should shoot a whole photo album and submit that to Cliff as a specific 850 clutch inspection. It really is not that hard. Mike has already posted some helpful hints and Im sure you will get more.....

Do your work on the side stand. You wont lose any oil.

Caliper to check the fibers and steels tolerance. A cheap one will be fine.

An impact wrench for the Hub nut. Kinda pricey. My auto store rents them.

I will take many many pictures as I go - it will serve the triple purpose of documenting for others (great idea), getting feedback on the state of my clutch, and showing others what I did wrong so that you guys can help me put it back together. It will also be kinda cool knowing my bike is on the GS Resources - if it makes it there.

Also, I'll buy some calipers and an impact wrench. What the heck! Do you have any suggestions for the calipers?

mike_of_bbg: Really good idea regarding the cardboard cut-out "jig". I will definitely do this!

 

[BassCliff]

Hi,

A 6" digital caliper should do for most purposes. Here's one at Harbor Freight.



Click the picture to be taken to their sales page. It's $20. At times you can find them on sale for less.

I haven't yet had the pleasure of working on my clutch but I'd be happy to host a write-up of your clutch repair experience. That would be grand.


Thank you for your indulgence,

BassCliff

 

[legaleli]

Part 1 - The Cover

Part 1 - The Cover

I bought new digital calipers:

And a 20 dollar air gun:

 

[legaleli]

I put my bike up on a lift with the oil drained from the crankcase:

I loosened the bolt holding the clutch release arm and moved it out of the way:

Using a sharpie I marked the bolt to the right of the Oil Cap #1

As I removed each bolt around the clutch cover I put it in a piece of masking tape with its corresponding number:

Ten bolts came out - one at a time. I numbered each bolt as they came out because it would be a bad thing to mix them up (they are of differing lengths)

This is what they look like now:

 

[legaleli]

The clutch cover was stuck on pretty good... probably because it hasn't been removed in 30 years. There were places on the cover that did not form part of the seal where I would place a pry bar. As the cover started to come away from the crankcase there was a "popping sound" as the seal came free:

The cover has to come off uniformly (as there are two post guides that hold it in place) so you have to find places on each side to pry it away. I made sure to NOT use any area where a seal is formed between the cover and the crankcase.

Once it started moving it came off with just my hands doing the work:

There were some BIG pieces of the old gasket hanging onto the crankcase and cover - they were very brittle. Note the guide post just below my thumb that helps orient the cover when placing it on the crankcase - there is another on the right side of the crankcase.

I pulled off the big pieces of gasket with my hands. A full cleaning of the seal area will take a bit of effort I think.

Note the oil on the floor - this is despite draining the bike on the centerstand for 10 minutes.

That's it for now... tomorrow part 2 - removal of the springs and plates!

 

[legaleli]

I'm going to post my guide later...

I'm going to post my guide later...

This will be more difficult to do than I fist thought. I will put together my experience guide when I am finished - rather than as I go along.

I need some help deciding what to do next. I have the whole clutch out... but the basket is still in place. Things seem smooth and rotate well... but should I go further in?

ALL the pics I have taken so far are at http://bakerlawoffice.ca/clutch/

I am going to measure up the plates tonight to see if they are thick enough. The springs have yet to arrive.

Do I need to take out the basket / should I take it out?

This is where I am:

 

[Steve]

Look at the grooves inside the outer edge of the basket. You are looking for grooves that have been worn by the tabs on the outer edges of the fiber discs. If you see ridges, use a file to smoothe them out. If you have ridges, the tabs of the fibers can hang up on them and will not release smoothly when you pull the lever in.

Use a Scotch-Brite pad or some 400 sandpaper to scuff up the glaze on the steel discs to give them a fresh surface.

When you put your discs back in, make sure they are turned the correct direction. You will see one side of the tabs that is polished more than the other. That will go to the side of the groove in the basket that might have had the ridges.

.

 

[legaleli]

Look at the grooves inside the outer edge of the basket. You are looking for grooves that have been worn by the tabs on the outer edges of the fiber discs. If you see ridges, use a file to smoothe them out. If you have ridges, the tabs of the fibers can hang up on them and will not release smoothly when you pull the lever in.

Use a Scotch-Brite pad or some 400 sandpaper to scuff up the glaze on the steel discs to give them a fresh surface.

When you put your discs back in, make sure they are turned the correct direction. You will see one side of the tabs that is polished more than the other. That will go to the side of the groove in the basket that might have had the ridges.

.

I will bring nice high res pictures tomorrow for your inspection! Thanks again... and again... and again...

 

[pyro254750]

Personally i wouldnt go any further as long as no play is felt in the basket. Youve gone far enough to accomplish the repair you set out to accomplish, and as long as nothing throws up a red flag that dictates going further, i would put it back together, thats just my opinion though. How many miles are on this clutch? If its old enough to need springs, then its probably old enough to need a clutch, so while it may not be burnt up, it wouldnt cost too much more to put a clutch in it, and it would save you having to buy another gasket and go through the trouble again in the near future. Just a thought.

 

[bonanzadave]

The impact gun is used to take off the hub nut. Flatten out the locking tabs first. This hub nut is made from soft metal and anyone in the (clutch) know will tell you to replace it with a hardened APE nut. Im not sure if this applies to 850s. Lets see what kinda feed back you get.
http://gszone.biz/clutches.html

 

[legaleli]

Personally i wouldnt go any further as long as no play is felt in the basket. Youve gone far enough to accomplish the repair you set out to accomplish, and as long as nothing throws up a red flag that dictates going further, i would put it back together, thats just my opinion though. How many miles are on this clutch? If its old enough to need springs, then its probably old enough to need a clutch, so while it may not be burnt up, it wouldnt cost too much more to put a clutch in it, and it would save you having to buy another gasket and go through the trouble again in the near future. Just a thought.

What does "play in the basket" feel like? How can I eyeball it?

 

[legaleli]

The impact gun is used to take off the hub nut. Flatten out the locking tabs first. This hub nut is made from soft metal and anyone in the (clutch) know will tell you to replace it with a hardened APE nut. Im not sure if this applies to 850s. Lets see what kinda feed back you get.
http://gszone.biz/clutches.html

Sounds good to me! I live for the feedback you guys give me - it is truly appreciated. I'm off to take pictures and take some micrometer measurements of the plates!

 

[legaleli]

Micrometer results

Micrometer results

All friction plates are between 1.93 and 1.94 mm thick.

Fiber plates:
1 2.75 (innermost)
2 2.75
3 2.76
4 2.77
5 2.80
6 2.81
7 2.81
8 2.81 (outermost)

Should I order new stuff?

ALSO... there may be a problem with the basket... I will post pics tomorrow concerning that...

 

[littleroot]

Thanks for putting this up - I need to do this soon, too!

 

[legaleli]

basket weaving....

basket weaving....

Picture #1 - The basket appears, on the sides near the posts, to be worn thinner than the rest of the basket wall - though it is next to each and every post... is this normal?

Picture #2 - When I discovered this I felt like an investigator for the Airline Transportation Agency discovering a crucial element... the inside of the basket is smooth and uniform. But within the green circle you will see that the surface looks "crackly"... and it FEELS that way too... it's like there is an issue with the metal - and it is in one place... thoughts?

Finally... the thicknesses of the plates described in my previous posts... how are they? ** note** I just noticed in the high res manual on BikeCliff's site that these limits are fine.

 

[rustybronco]

the hub and basket are fine and the "crackly" surface is not a flaw in the hub.

are the steels blued or warped? if not, check the torque on the nut, install the new springs, waste a gasket, slap it back together and see if it slips.

 

[legaleli]

the hub and basket are fine and the "crackly" surface is not a flaw in the hub.

are the steels blued or warped? if not, check the torque on the nut, install the new springs, waste a gasket, slap it back together and see if it slips.

The steels are perfect / no warps or discoloration. I am a little worried about getting the fiber rings in the right way when I reassemble the plates into the basket... I understand that there is a "right side in".

When it comes to the nut - I guess that's the big one in the middle of the basket with the locking tab... what do you suggest should be the torque pressure?