The New And Improved Unofficial R65 Forum V2
Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: Dave 2 on December 12, 2011, 10:53:53 AM
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Hi There, I'm trying to remove my clutch "assembly", So far I have wedged a small block of wood against the Housing Cover, I the removed the six bolts that secure the clutch to the Flywheel. The clutch shows no intention of giving up easily :-? I then decided to spray PT Blaster freely trying to get in between the stuck pieces...after an hour of soaking the clutch still is not responding. Do any of you have any ideas as to what I should try to do? Thank You as always [smiley=bmw_smiley.gif] D2
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If the cover isn't separating from the flywheel, it must be corrosion at the union of those two parts. I've never run into that problem. But I have run into corrosion often, and there are many tricks - heat, cold cycles, penetrating oil (acetone/ATF supposedly THE best), vibration (not pounding), sheer forces - like trying to slide rather than pry.
It'll break loose, just be ready to catch it when it does. Or perhaps thread some twine through it and fasten to the frame.
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One trick i find usefull is to cut the head off an 8mm bolt put it in a hammer drill and aply to the unmovable object with a dose of gas oil or WD40 it usualy works.
Lou
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Thanks for the good info, I don't have a hammer drill so I'll just apply more solvent and try to slide it off and just keep at it. D2
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I would [size=16]IMMEDIATELY[/size] replace three of the screws (every-other one) and screw them down until there is only 1mm or so of play in them. That way, when the cover does release, it will be doing so in a safe environment. Right now you have a ticking time bomb.
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+1 with Rob - ya gotta be a bit careful as that diaphragm spring is pushing against things some - while it won't pop the carrier/cover plate off in a way to kill you, it could still cause alot of pain or broken fingers if it decides to let go and your fingers are in there.
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Oh, and after you replace the 3 screws, try tapping on the clutch assembly with a small plastic hammer.
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THANK YOU FOR THE WARNING ABOUT THE CLUTCH, My ignorance can be a hazard to my health :o I did not realize or failed to understand from Clymer the dangerous nature of the beast. I'll go put those 3 bolts back right now. D2
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And if you have plans to pull the flywheel (or clutch carrier - I'm not sure what year bike we are talking about...) - DON'T FORGET TO BLOCK THE CRANKSHAFT FIRST! (from the front)
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Thanks Rob, All I intended to do was to remove the clutch for inspection and to grease where necessary with Moly 66 and Sig3000. The Clymer Book does mention blocking the crankshaft for flywheel removal. It just does not discuss potential dangers removing the clutch assembly. Thanks again.D2
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For future reference, you can get metric hardware from Ace Hardware stores, a ,ot cheaper than the 'tool' that available, which is just three bolts and nuts .
I picked up three long, I believe 7 mm diameter bolts and nuts .
The manual says to remove three of the bolts put the long bolts in and then tighten the nuts, as a jam-nut, remove the remaining three original bolts, then back off the jam-nuts on the three long bolts to relieve the tension from the spring .
It is also helpful when reinstalling the clutch, to use the three long bolts and jam-nuts to compress the diaphragm spring, if you can't get the bolts started .
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Thanks Bob for another fine idea :) D2
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I did want to report that the three 7mm bolts and nuts worked nicely to free up the stuck assembly. I now have them apart and I wonder if my liberal application of BP Blaster has ruined my clutch plate. I will take it to a mechanic who is familiar with dry clutches if I can find one, however I wonder if there is some rule of thumb about how to tell if the plate is toast? Thank You, D2
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There is a thickness measurement of the friction material, and a 'depth' measurement of material thickness above the rivet heads to determine clutch wear, but as far as surface glazing or becoming contaminated, well, I think that it is better to be conservative and if in doubt-toss it out given how much time is involved to get back in there to replace it if you assemble everything only to find it slips while going up hills under load. I've heard of folks boiling rear brake shoes to remove oil contamination from the shoes, but at least with rear brake shoes, it is comparatively easy to go back and replace them if they still aren't working right, plus, their functionality is so often used as the clutch.
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I think that it is better to be conservative and if in doubt-toss it out given how much time is involved to get back in there to replace it if you assemble everything only to find it slips while going up hills under load.
I guess I will have to swallow the bitter pill of the cost of a new clutch, but I agree that it is better to make sure. I know the feeling of trying to accelerate and having only the engine getting with the program. :-? thanks,D2
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Maybe I don't push these bikes that hard, but I have had the slipping clutch phenomon - so guess I've been lucky. I've never replaced a clutch (of my own) that had some oil on it. I cleaned them off best I could till they had that new sort of look, sanded perhaps, and used em. Brake shoes, same thing.
Here's what I figure: old grease gets really sticky! Ever notice! So if you get as much off as you can, then take it easy at first (you should take it easy on a NEW clutch anyway), the heat will boil off the rest and make it real sticky! :-)
PB blaster is real thin and should clean off pretty easily. I wouldn't worry about it. Use any good solvent - and maybe finish off with brake cleaner.
All this is assuming it's still within servicable limits?
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I guess I will have to swallow the bitter pill of the cost of a new clutch, but I agree that it is better to make sure. I know the feeling of trying to accelerate and having only the engine getting with the program. :-? thanks,D2
When my clutch started slipping a little at about 100,000km I had the drive plate relined for about $100. Because the clutch hadn't been allowed to get too hot, the spring and pressure plate were fine, and with new thicker friction material it was like new.
Any decent brake place (as opposed to franchised parts installer) should be able to reline the driven plate. They will want to know how thick it should be.
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A tip, on having the clutch disc friction lining replaced .
About 5 years ago, I took the two plates to be machined and have the clutch relined, to make a long story short, the machining workmanship was horrible .
After installing the reworked parts, I couldn't get the proper adjustment at the adjustment bolt at the back of the transmission .
Needed a bolt about 6-8 mm longer, that cured the problem, seems like the thicker the friction lining the longer the bolt you need .
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Taking everyone's thoughts into consideration I decided to go over the clutch surface with 220 wet/dry sand paper to clean it up and then I gave it a good scrubbing with brake cleaner [smiley=mad.gif] (I moved that operation outside!) Then I showed the clutch to the foreign car mechanic in town and he said it looked as good as new, with barely discernible wear [smiley=bmw_smiley.gif] So I should be good to go with that. D2
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How much friction lining do you have past the rivet heads,?
That's pretty much the determiming factor on clutch wear .
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Bob, I have an overall thickness of .230 inches or 5.842 MM. Clymer calls for 4.5 mm so I should be good with that measurement. I used a 6" Dial Caliper to measure so I'm not positive of my measurement from the top of the rivets to the surface of the disc but it was approx. 35 mm. I do not have a table for that measurement, does this sound OK to you? D2
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I really don't know, when I replaced my clutch disc, I forgot to measure what the distance was from the rivet head to the lining surface .
If you are well within what the manual calls out for, I don't think I'd get concerned about it .
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New is 6mm, worn out = 4.5mm. Yours is very close to new.
They wear more on the edge than towards the center. Did you measure on the outer edge?
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Yes Sir, I measured around the outer circumference. D2
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That's excellent! You've got yourself a good one.
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FWIW - most dial calipers I've seen also have a depth measurement (which slides out from the bottom of the 'handle/ruler as you adjust the wheel). You would use this to put against the surface of the friction material and measure the depth of the rivet head in the hole.
In any case, it does sound like yours is only slightly worn as they are right around 6mm thick out of the box.
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Yes, I used that slide out rule, but my eyes are not what they used to be :o so that measurement of .35 is a little iffy. D2
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Hi Dave - back online at last. I'm trying to catch up with your posts as we are doing the same work. I'm not going so fast but I'm managing an hour most days. Thanks to you the mystery of clutch and wheel bearing removal has been simplified. I shall save a fair few dollars now as I have the confidence to tackle these jobs myself. You mentioned in one of your posts about having the wheels powder coated. Did you get a result as yet? I'd be interested in what you think about the results. Thanks mate hope yer well. Adrian
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Hey Adrian good to hear from you again. I appreciate your comments but I just asked the questions and all the good folks who answered them deserve our thanks. I think it is so cool to get the confidence shared by others to tackle the restoration process. The mystery of things like a stuck clutch goes away real fast when you can actually take it apart and see for yourself how it works [smiley=bmw_smiley.gif] I'm still waiting for a tool part to arrive in the mail so I can remove the swing arm bearings. The foreign car mechanic up the street said I could bring the swing arm up and he will use his press to separate the driveshaft. Then I will get the frame and wheels taken care of. The way things go I figure in two weeks I'll have some pictures to post. Happy New Year mate. D2