The New And Improved Unofficial R65 Forum V2
Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: dziadzu42 on September 12, 2015, 01:46:19 PM
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My R65, 1979 w/ app. 50,000 mi. shifts like an old John Deere tractor, esp in the lower gears. It clunks, and grinds a bit when going down, i.e.. 3 to 2 , 2 to 1,and occasionally when shifting up. Any thoughts?
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When was the last time a transmission input spline lubrication was done ??
Have you checked the clutch cable adjustment ??
Probably not a factor, how long has the oil been in the transmission ???
These aren't the smoothest shifting transmissions, compared to Asian bikes, if that is what you are familiar with .
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Smooth downshifts are always going to be more tricky than up shifts as it's just easier to let the revs fall than it is to increase them. Also the bigger the ratio gap the harder it is to match the revs and the gap between ratios is much bigger in the lower gears. I have an easy solution for the 2nd to 1st down shift - I just don't do it and for the life of me don't understand why it's needed on a regular basis. That after all is the reason neutral is between 1st and 2nd. If we were meant to change down to 1st on the move neutral would be before 1st.
My test for whether there is something amiss would be to try changing up from 3rd to 4th to 5th without the clutch. If you can do that smoothly there is nothing much wrong and everything else is down to timing.
An airhead transmission is never going to be as easy as most other bikes for the simple reason we have an engine speed clutch and gearbox and everything is moving faster with more inertia than a typical bike with primary gear reduction.
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My R65, 1979 w/ app. 50,000 mi. shifts like an old John Deere tractor, esp in the lower gears. It clunks, and grinds a bit when going down, i.e.. 3 to 2 , 2 to 1,and occasionally when shifting up. Any thoughts?
Sounds about right actually......
Seriously, slow deliberate shifts using the clutch are a requirement for these old girls, if you are used to Japanese type gearboxes then there is a learning curve.
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You may also be in need of a clutch adjustment and/or spline lube - these things greatly help - but even on their best day - these are old fashioned gearboxes with several straight cut gears and no synchros, so shifting is not something to be hurried, or done without deliberate intent.
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When up shifting, try preloading the shift lever. Especially going from first to second. Downshifting an Airhead gearbox requires learning to match engine revs to the next gear based on road speed and a "learned" boot. As mentioned, if you've grown up on multi-plate, wet clutches, you'll have a learning curve with the single plate dry clutch.
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Sorry to say live with it! BMW R65s are tractor like.That is how the germans make the things some what reliable. My 1974 Jawa 634 has better manners, just not as quick and as reliable.
You just cannot help but love them both. :)
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I would try some Green Paint that may help ;D
I thought I had some thing wrong with mine also but when I took it apart to rebuild it I realized that is just the way the are.
You just have to learn how to shift it
You can get to a piont were you dont even have to use the clutch at times.
Pre loading and post loading the shifter helps a lot as others have mentioned :D
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Thanks all. I kind of suspected it was a characteristic of the make.
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Main thing is don't let it put you off the bike. After a while you'll cease to think about it
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Something to keep in the back of your mind regarding shifting the Airhead box...
If you enjoy hustling around twisty roads as much as I do, avoid downshifting while in the middle of a fast turn. The driveline doesn't like it. Your "rubber cow" quickly becomes a "hopping black crow".
I quickly learned to select the gear for the turn and get into it prior to cranking hard over and getting on the gas. Up shifts are done as the bike, with me still on board, exits the turn.
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I just bought a 1980 R65 and when I checked it out with the seller, the shifting was terrible. It was a reason to talk him down on the price (only $50 but every little bit helps).
I got home and took apart the linkage for the shifting/tranny/arm and the grease pivot was completely gummed up. I cleaned it, lubricated everything and bingo! Shifts as one would expect. Of course a spline lube and tranny oil change was done as well.
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Airheads are also very sensitive to clutch cable adjustment... following the steps in the factory manual provides the best results
(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fi1170.photobucket.com%2Falbums%2Fr534%2FR100RT_Mark%2Fclutch_throw_adjustment_zps4ce277b3.jpg&hash=696cb77b20c81ad0399013c4da5107f9fb4c71a4)