The New And Improved Unofficial R65 Forum V2
Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: Rubi76 on January 22, 2012, 03:39:16 AM
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Got up early this morning to take the bike for a Sunday run and noticed a unusual noise while pushing the bike out the garage with the engine off. Put the bike back on the main stand and rotated the back wheel.
It seems to get to a point and has a clunk sound with a tight spot. Sounds like it comes from behind the gearbox.
I did not notice this noise before when moving the bike.
Is this the sound of finished drive shaft ? :o
( This is depressing if it is the case after having the bike for only 2 weeks :'( )
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Is this the sound of finished drive shaft
Could just be a loose bolt or bolts #3 where the drive shaft connects to the gearbox output flange. Feel through the rubber boot #4 as you rotate the wheel.(http://)
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Thanks for the diagram Barry
Ok, felt around the boot.
Decided to loosen the boot and have a look. All looks fine and secure.
A bit of oil came out not much.
Is it time to strip it yet ?
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Drive shafts are very reliable and failures are rare. There is the spring loaded damper in there though. Any further insight into where the noise is coming from ?
Might be worth waiting to hear some more responses. Bear in mind that those bolts are not meant to be re-used but in principle If you disconnected the drive shaft from the gearbox you would be able to tell if the source of clunk is the gearbox or drive shaft/final drive. Before you do anything is the noise there with the clutch lever pulled in ?
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Just an idea, Isn't it possible to isolate the problem by putting the bike in neutral then turning the wheel around?
If problem persists, then it could be the driveshaft itself, or if it goes away, then the gearbox should theoretically be at fault.
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The ujoint bolts can be re-used, contrary to earlier specs and popular belief. If it's possible to thread them in by hand, then they're not stretched and ok to re-use.
Also, please note the lock washers in that diagram. DO NOT INSTALL WITH LOCK WASHERS!!!!
However, if re-using the same bolts that had lock washers previously, either shorten the bolt or use flat washers to take up the extra distance. If the long bolts are used, they'll damage the transmission output seal.
When the transmission is in neutral and the wheel rotated, the transmission output shaft will still rotate, but not the input shaft. Pulling in the clutch in gear will cause everything up to and including the clutch to rotate, but not the flywheel.
I've got a horrible feeling your transmission output shaft front bearing is disintigrating. Pull the transmission drain plug and inspect the magnet. Tell us what you find.
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Mis-adjusted swing arm bearings, causing the drive shaft to contact the swing arm housing, is a remote possibility .
How does the gap on each side of the swing arm to frame look ?
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On my '95 RT I had a clunk similar to that described and it turned out to be the rear output shaft bearing in the tranny...
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Hi Guys ,
Ok, Put the bike in Neutral, and pulled the clutch in.
Rotating the back wheel and the noise is still there. Swing arm checked and looks perfectly centered.
Will check the transmission drain bolt and have a look for debris , if that looks ok will have to pull the swing arm and isolate the transmission from the drive shaft to see if the noise / tightness persists.
Any other ideas ?
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It may be the u joint then (less work to replace) or possibly the cush drive spring has failed (more work to replace, but generally a very rare failure). To diagnose either and isolate from the transmission, will require disconnecting the drive shaft from the transmission output flange inside the rubber boot by the swingarm pivots. I would order a new set of (4) of those 12-point bolts from the dealer - especially if you have the older, longer ones with the nut&lockwasher on each. The new stretch bolts work well and are preferred.
This way you can rotate&manipulate the u-joint and check it for binding or play, and separately rotate the output flange of the transmission and feel for roughness in its rotation.
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You are getting conflicting views on drive shaft bolt re-use. New bolts is the official view and it must be the safest but some people have re-used them without problems. That would be your decision after doing some research. If you do re-use them I would use loctite and only torque to the lower end of recommended values. Here are some links to info on drive shaft bolts that give the hard line official view and an alternative view from Snowbum who is happy to re-use them. As wirespokes said the theory is if you can screw them in by hand then they can't have streched much which suggests they are ok to re-use.
http://www.horizonsunlimited.com/tech/bmwairheads
http://bmwmotorcycletech.info/drvshftboltstoolstorque.htm
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Update:
Stripped off the Swing arm and found the drive shaft to be very snug.
Rotated the output shaft when the gearbox is in neutral and seems to be very tight to turn and has a tight spot when turning.
I took a video with my cell phone
http://youtu.be/m5zv_DAhw1s
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Evidence is pointing more to the transmission. There was no need to pull in the clutch while rotating the wheel in neutral - the input shaft is disconnected from the power train at that point. But the output shaft IS still rotating, and that's the one with the troublesome bearing.
The front (towards the front of the bike) bearing on the output shaft is the one that normally goes bad first. What tends to happen is the bearing cage fractures, and since that bearing is somewhat isolated, the debris recycles through that bearing. Once it starts to go bad, it disintigrates very quickly. But the first thing to go is the bearing cage. Without the cage to hold the large ball bearings in place they migrate to one side allowing the shaft to shift, which then minimizes gear mesh. That clunk you're feeling is the shaft flopping around in there.
Checking the magnetic drain plug is easier than separating the driveline, so I'd have done that first. If concerned about possibly unnecessarily draining the gear lube, it's possible to quickly plug the hole with a finger while inspecting.
Even so, draining the fluid into a clean container enables you to easily pour the contents back in should there be no contaminants.
What you're going to find on the magnet is more than soft fuzz (acceptable) - it's going to be slivers and chunks.
This may seem like horrible news, but there is an up side. You're extremely fortunate to discover this now rather than on the next ride when the box starts emitting screechy clunky noises and the gears are trashed and not re-useable.
Since this is a new bike to you, I'd contact the seller and let him know what you've discovered. Hopefully he'll refund some of the purchase price. So hurry up and check the oil - that's an important step in diagnosing this one.
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Looks like you have found the problem perhaps to be confirmed by metal fragments on the drain plug.
I guess we all try not to be too pessimistic but with the drive shaft being usually reliable it was odds on to be the potentially more expensive gearbox.
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:'(
So it wasn't just my Sunday that was ruined but my whole week
Drain plug removed and this is what I found.........
(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fwww.suraklyn.com%2Fr65_forum_gallery%2Falbums%2Fuserpics%2F13122%2Fnormal_SDC11890.JPG&hash=d29947aa87d5e8676dfc4fb22601265f3420b87b)
Looks like you hit the nail on the head there Wirespokes, so now to pull the gearbox off the bike.
Is this a job I can do myself or will I have to send it to someone that is a specialist ?
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You can easily remove the transmission yourself. However, the swingarm must be detached at its pivot points to allow space to pull the gearbox aft and out.
The primary tool you'll need is a 27mm socket. The fly in the ointment is that most available sockets have too large an outer diameter to get to the swingarm nuts. If you find one that does reach, the rounded opening prevents good purchase on the thin nuts. Hum...
You can buy a modified socket or have a local machine shop turn down the outside of the socket and mill the socket to end up with a flat, rather than rounded, opening.
Here's a couple link with a photo that will help you visualize the modified socket.
http://www.cycleworks.net/index.php?main_page=product_info&cPath=29_33_50&products_id=58
http://www.culayer.com/Joes_tools.htm
The bearing work may need to be done by a decent BMW specialist.
Monte
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Hi Montmil,
The Swing arm is off the bike already, I had a 27 socket that fitted perfectly ( what luck :o )
Will remove the gearbox in the morning and get hold of BMW to see if they will be able to recommend a specialist. Anything else I should check while I have everything apart besides the Clutch splines ?
I wonder what a gearbox repair will cost .........
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Cape Town SA? I have no idea. How many miles on the bike?
Mine is up just past 110,000 miles and still running. Nathan at Boxerworks says it's time for some new bearings and an overdrive top gear.
But the dawgone thing still runs!
Changing out the oil twice a year: Valvolene 85W140 in the summer and 80W90 in the winter -- dark blue bottle from Autozone.
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The bike has got 63000km so about 39 000miles.
It was shifting and running fine. I just noticed the noise when pushing the bike out the garage ( suppose that was lucky that I did not ride further causing more damage )
Well at least now I can paint the swing arm where it has slight surface rust.
At least most of the work I can do myself :)
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... I had a 27 socket that fitted perfectly...
While you wait on the gear box fix, you may want to use a belt sander and dress the end of that 27 mike-mike socket. Your swingarm refit and adjustments will thank you. IMO [smiley=whistling.gif]
Monte
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Sorry about that! I really am. :-[
And, no, this isn't an easy fix - some high level training is required, plus a bunch of expensive tools. But pulling the transmission is something you can do. The only thing you might find confusing is the UJoint bolts. They're twelve sided and look like they'd need a special wrench, but in fact take a normal 12 point box end wrench. If you don't have a long one, put it on the list.
The cheapest path is sourcing a good used transmission. Look for one 83 and newer. If you decide to have it rebuilt the parts come to about $100, and if you're lucky, won't need anything extra like gears, bushings or any of the other expensive parts in there. It's the labor that doesn't come cheap. Here in the states it's not uncommon to spend $1000 on a rebuild.
There are two ways to pull the transmission - remove the swingarm axles and move it back. That requires a ground down 27mm socket.
The other method leaves the swingarm in place and lifts up the rear of the engine. Place a jack under the rear of the engine, remove the rear engine mount bolt and raise the rear enough to pull the trans. You'll need to remove the mufflers, but the headers can stay on. This is the way I like to do it.
It's not a difficult job, but the first time may take a little while. Still, it shouldn't take you more than two or three hours. Pull it out the left side.
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Gearbox is out !
Was rather easy to get out of the bike with the swing arm removed. Clutch looks ok :)
Now to get the gearbox sorted.........
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Just a quick update :
Gearbox has been repaired. Turns out that only the front output shaft bearing was faulty and had just started going. So no other damage was done.
All bearings have been replaced along with all the seals.
Now just to get the bike back together ;)
(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fwww.suraklyn.com%2Fr65_forum_gallery%2Falbums%2Fuserpics%2F13122%2Fnormal_g2.JPG&hash=eb3b5f2f9a49d44b132f7d11b3b4130a508be7e0)
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I've got a horrible feeling your transmission output shaft front bearing is disintigrating.
Wirespokes prophesy was spot on very early on in the thread.
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I've got a horrible feeling your transmission output shaft front bearing is disintigrating.
Wirespokes prophesy was spot on very early on in the thread.
The oracle [smiley=rolleyes.gif]
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Indeed :)
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;D
You guys are funny!
Actually, once you've seen it a few times, it's a 'no brainer'.
Right now I'm working on two transmissions (with a third coming) with the same common cause for tear-down - the front output bearing. Of course, there can be other things, like the shift pawl spring, or worn bushings that allow it to pop out of gear, broken dogs - but that bearing is the biggie.
One of the trannies just needed the cover replaced due to (what appeared to be) a broken output boot flange from an accident. Once opened, there was shinny sparkly gritty stuff sprinkled around. Bad sign. Turns out the output front bearing had slid on the shaft (no circlip) and was beginning to deteriorate - sloppy. That's where the debris was coming from. Luckily it wasn't very far along and the rest of the transmission wasn't harmed.
Maybe five years ago my R80G/S started making whining noises. I noticed the oil was sparkly and the magnetic drain plug had slivers on it. Right then, if I was smarter, I'd have known to retire that transmission and get it worked on. But I wasn't, and I didn't, and added some Lucas oil additive hoping to quite things down and... who knows what I was thinking?
So I rode it another thousand miles like that and it seemed to be fine. Until...
I was 400 miles from home heading to Crescent City CA (about 20 miles away) and got horrible crunching noises in the gearbox. Nothing I could do at that point but stay out of third and fifth. Rode it another couple hundred miles that day to a friend's place, and from there trailered it home.
That was one of the first transmissions I worked on, and let me tell you, it was sickening - trashed the fifth gears and made a mess of a lot of stuff. All because of the front output shaft bearing!
So you don't need to ask me, because you now know - I've been there, done that, got the T. Personally, and seen it with others enough times to know it's very common.
Moral of the story - nip it in the bud! Recognize the signs and pay attention - if there's anything more than soft fuzz on the drain magnet - get it fixed NOW! It's a hundred bucks in parts - gaskets, bearings, seals - for a normal rebuild, but your transmission may not be worth rebuilding if taken to the extreme that mine was.
Just so you can visualize what's happening here - look at it like this:
That front bearing is a ball bearing. It's got maybe seven big balls with a cage that holds them separate from each other. The cage is two metal strips, one to a side, that are riveted between each ball. What seems to happen is the shocks and stresses wear that cage, eventually cracking it. From there it begins to fall apart allowing the balls to collect on one side - the side away from the other gear. The debris from the cage wears the bearing even more and everything goes down hill very quickly.
The clunk you were hearing or feeling was due to the bunching of the balls and the uneven rotation of the output shaft, and the uneven mesh of the gears.
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Very True Wirespokes ,
The specialist the repaired my gearbox for me is a Ex BMW mechanic and said he has done hundreds of these gearboxes over the years.
Most of them because of the front output shaft bearing.
Also he told me to only use GL4 Gearbox oil and not GL5.
My bearing was still intact but very rough. I doubt it would have lasted many km before self destruction as you described.
http://www.youtube.com/watch?v=RnTBM6GDJ4Y
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Even though it was an unexpected expense, I consider the outcome very good news. You definitely did much better than I did for my first experience!
Well done!
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Glad all is working out.
My very first post here was asking why my tranny wouldn't shift - (poor Tina) who was exiled to the harsh MN winters!
And - what's this little wire clip that came out of gearbox drain plug?
Turned out to be a broken pawl clip. I contacted Matt Parkhouse who writes the Keep Em Flying articles for BMW Owners News and shipped him the gearbox. He did a wonderful overhaul and was very reasonable.
R65 shifts better than K75s! Sometimes I need to remind myself that the R65 has a fifth gear!
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Matthew Parkhouse did install a new Pawl clip - what is the likelihood of it breaking again?
Wondering if it broke because the tach cable boot was off and let water get into the tranny - when I got her and removed the drain plugs, the fluid starting rising out of the fill hole - it was then a member or two suggested I put a heat lamp under the bike to thaw out the water mixed with gear oil. After everything loosened up, that's when I saw the Pawil spring dangling from the drain hole.
Is it a a clip or spring and what is its function?
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The spring puts tension on the shift mechanism, when it breaks, you are usually stuck in one gear .
http://www.realoem.com/bmw/showparts.do?model=0364&mospid=51897&btnr=23_0268&hg=23&fg=31
It's reference # 6 in the diagram, it keeps tension on the shifter pawl, #8 in the diagram .
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Is it a a clip or spring and what is its function?
It's a spring and properly designed and manufactured springs shouldn't break so you would have to say there was a marginal design or manufacturing fault involved somewhere. That being the case you would expect BMW to remedy that with updated parts so it wouldn't happen again. I read somewhere that the early 80's "shift Kit" fixed the problem by making the spring less likely to bind.
Mine doesn't have the shift kit but it's not something I worry about.
There was a thread on I think the airheads list where a guy claimed that in the event of the spring breaking you could change gear by poking a bit of bent wire through the level hole. Sounds unlikely and can't remember if it turned out to be a proven technique but if it was it ought to be the No 1 tool to carry on a long trip.
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Are you the picture shows the pawl clip #6? on link you provide above?
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It's #7 part No 23311242 910
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There was a thread on I think the airheads list where a guy claimed that in the event of the spring breaking you could change gear by poking a bit of bent wire through the level hole. Can't remember if it turned out to be a proven technique if it was it ought to be the No 1 tool to carry on a long trip.
I recall seeing that ages and ages ago. I may have to experiment with that while I've got these transmission parts on the bench.
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Back on the road......
it took a bit longer to put the bike back together than it took to strip but just in time for a Sunday morning ride down the coast.
Gearbox is quiet now with no funny noises but still no change in the way it shifts ::)
(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fwww.suraklyn.com%2Fr65_forum_gallery%2Falbums%2Fuserpics%2F13122%2Fnormal_Pringle_bay_small.jpg&hash=328ab4ff9ef36ba19bcc237fdacb0f94782e83d6)
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Congratulations!
Would love to get to Capetown and join you for a ride in this lifetime!
Was there in 1973 and wow - what a beautiful place - I remember Table Mountain.
Back in the late 1800's my great grandfather had a horse drawn carriage taxi business.
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Fine looking bike!
What's the problem with shifting? I don't recall - are you new to BMWs?
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Hi Wirespokes,
I had a 1200GSA and a 1200S ( and a K100RS ) before the R65 , I just have to get used to the slower shifting required from the R65 gearbox. I am sure after a few hundred miles it will become second nature ;)
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Congratulations!
Would love to get to Capetown and join you for a ride in this lifetime!
Was there in 1973 and wow - what a beautiful place - I remember Table Mountain.
Back in the late 1800's my great grandfather had a horse drawn carriage taxi business.
Ken , Im sure Cape Town has changed a lot since 1973 but Table mountain still looks the same.
I have lived here for 2 years now. Great place to explore on a bike
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Hi Wirespokes,
I had a 1200GSA and a 1200S ( and a K100RS ) before the R65 , I just have to get used to the slower shifting required from the R65 gearbox. I am sure after a few hundred miles it will become second nature ;)
I was wondering if that was the case. Once used to them, shifts will become much swifter. But it does require little tricks like - backing off the throttle a little (clutch still engaged) which removes pressure on the gears - kind of like speed shifting. These bikes require YOU being in tune with them, not the other way around. Someone once compared these BMWs to the gorgeous proper German Scientist Chick who does calculus in her head and demands things be done her way. She knows all the positions from the Kamasutra and once you figure out how to deal with her she'll give you immense pleasure.
It is a lot like that.
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Wow, wireguy! I salute you on this Stupor Bowl Sunday [smiley=thumbsup.gif]
Your segueing from shifting an old Boxer transmission to doing the deed with the German chick is literary genius.
And ol' D2 wonders what I've been smoking. [smiley=whistling.gif]
Glad you're back on the road, Rubi76.
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Wow, wireguy! I salute you on this Stupor Bowl Sunday [smiley=thumbsup.gif]
Your segueing from shifting an old Boxer transmission to doing the deed with the German chick is literary genius.
Glad you liked it!
The original was so good, I had to reproduce it here for you guys. It was in an Adventure rider thread comparing Airheads to Guzzis:
I always liked this little bit of prose. Originally written by Chopperman:
Well BMWs are like the Hot German Scientist chick. Glasses, prim, mannered, efficient. She can solve quadratic equations while kicking your ass with kung-fu moves. You have to approach her on her terms and then she will bring you ecstasy in the most efficient manner possible using techniques she learned from an ancient Kama Sutra she discovered on a sabbatical in India.
Guzzis on the other hand, are the art school wild child. long, wind-tossed hair and mischievous winks. She will redecorate your house into a turkish harem while you are away on a business trip and greet you with absinthe tainted kisses. You will go out for pizza with her and wind up somewhere in the Mojave, tequila drunk and shooting cactus with a stolen pistol.
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Now we are really out there [smiley=beatnik.gif] Enjoy the rides D2
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After reading that I am beginning to think that "Chopperman" is a pseudonym for Hunter S. Thompson. Considering his history with motorbikes it just might be...