The New And Improved Unofficial R65 Forum V2
Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: Cliff A. on February 10, 2016, 06:38:09 PM
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The (original) throttle cables on my 1984 R65ls have very little moment.
Bike has sat for 4 years
Having read some of the post on the forum this can be an interesting undertaking.
They have one cable running down from the grip to a splitter under the tank.
Lube? inspect? replace?
Appreciate any and all help.
Thanks
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You may want to make sure your throttle shaft are free.
Try to lube and see what happens.
I think the service manuals say not to lube them.
I replaced mine
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Yes, the OEM grease within the twist grip assembly may be as hard as the same grease in the steering stem bearings. There may also be old grease on the handlebar portion beneath the throttle tube.
The two gear-toothed elements inside the throttle assembly go back together properly only if the small alignment marks -one on each gear- are directly opposite each other.
If you have not yet confirmed smooth operations of the carburetor's butterfly shafts, check those items, too.
The throttle cable junction 'box' is more fun than a Rubic's Cube!
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Y
The throttle cable junction 'box' is more fun than a Rubic's Cube!
I agree. The first time I was confronted by a Rubic's cube, way back in the 70s, I looked at at while, derived how it worked and pulled apart and put it back together solved.
The first time I was confronted by BMW's dreaded cable junction box I recall a lot more swearing and frustration. And what really, really irritated me was that like so much that BMW does it was a solution to a problem that didn't exist, and created new problems all by itself.
I have accumulated the necessary parts to revert my 1984 to twin throttle cables - take that BMW!
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The throttle shaft on the LH carb is froze up.
It is soaking in some penetrating oil
Monte
is your comment (The two gear-toothed elements inside the throttle assembly go back together properly only if the small alignment marks -one on each gear- are directly opposite each other.) to do with the hand grip and chain gears? I had that apart and didn't see any marks.
Thanks all
Never was any good with a Rubic's cube
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Do you lube your cables?
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... is your comment (The two gear-toothed elements inside the throttle assembly go back together properly only if the small alignment marks -one on each gear- are directly opposite each other.) to do with the hand grip and chain gears? I had that apart and didn't see any marks.
Clean and examine the throttle twist tube. You may see a part number cast into the area near the gear teeth. Look closely for a short, straight scratch mark approx 180 degrees from the cast number. This will align with a small, raised ridge on the throttle cam gear.
To aid in correct assembly, place the throttle tube on to the handle bar and position it with the mark on top. Lay the cam gear in place with the chain extended outward as far as it will go. You will probably spot alignment ridge adjacent the scribed mark.
If there is no ridge guide on the throttle cam gear, mesh the gear with the throttle tube and test with the cable and cover plate installed. Peek into the carb intake and check that the butterfly valve is fully opened. If butterflys are open and you have no twist grip binding, you're good to go. Perhaps mark both gears for future reference.
Sounds fiddly but it's really not
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... If you have not yet confirmed smooth operations of the carburetor's butterfly shafts, check those items, too.
How's 'bout dat! Even a blind hog finds an acorn now and then. :D
Could be corrosion. There are two small o-rings on each shaft. Plus, to remove the shaft, you must v-e-r-y carefully figure a way to safely remove the two small brass screws holding the b'fly to the shaft. Then there's the question wether to peen or not to peen the replacement screws. Bend that brass shaft and, well, don't do that.
If you can free up the shafts, I'd leave them be until you get the engine making steam. Then, you can decide about the shaft issue, if it even is an issue.
I've never lubed a throttle cable on any of my three Airheads.
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You may want to make sure your throttle shaft are free.
Hey i said it First :P
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Thanks, will proceed
But, just stop your fighting
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Then there's the question wether to peen or not to peen the replacement screws. Bend that brass shaft and, well, don't do that.
I didn't peen and the motor ate the screw in less than 10 miles
Just say'n.................
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Then there's the question wether to peen or not to peen the replacement screws. Bend that brass shaft and, well, don't do that.
I didn't peen and the motor ate the screw in less than 10 miles
Just say'n.................
Ouch! That's gonna leave a mark. :'(
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A hidden problem with a stiff throttle, is the gears in the throttle housing .
They are made from cheap ' pot metal ', they wear and bind up the throttle .
The throttle and choke splitters are not that big of an issue .
The problem with from what I've seen, the ' 82 and later bikes have problems with removing the cables from the plastic plug inside the splitter .
Had me puzzled for a bit !!!
Solution, open up the slots on the plastic plug at the top of the grooves for the cables, so the cables can come out the side of the side and not the top .
Once you do it a few times, it's only a two minute job .
I used to lube the cables every year, but when I got my oilhead 14 years ago, I decided not to lube them and see what happens, 14 years and 60,000 miles and still no issues .
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I didn't peen and the motor ate the screw in less than 10 miles
Just say'n.................
Ouch! That's gonna leave a mark.
I got lucky and it just left a few dents on the head and a few on the crown, nothing deep. Dremel'd the sharp edges and continued to march.................cudda been a lot worse.
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If there is no ridge guide on the throttle cam gear
... clean the grease off and look again.
Speaking of, I need to lube said gears. any particular sort of grease recommended?
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If there is no ridge guide on the throttle cam gear
... clean the grease off and look again.
Speaking of, I need to lube said gears. any particular sort of grease recommended?
Exact question popped up on the Airlist couple days ago. Consensus is to use a "cold temperature" grease. I've used a high temperature grease in bearings but not sure what a "cold grease" specs at. Maybe just a dab of plain ol' grease-grease?
I use a very light application of white lithium grease.
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I confess mine don't get cleaned and lubed every year, more like every 2 or 3 years. They must be due and this time I'm going to try moly grease on the grounds that normal grease turns black with wear particles from the pot metal gears so clearly it isn't good enough at preventing wear.
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Cleaned and lubed mine today. The throttle tube gear was a little worn even at only 21,000 miles but only the first few teeth. The cam gear must be mad of sterner stuff because I saw no evidence of wear on that at all.
There is an alignment mark on mine but frankly it's not particularly useful or needed. It's obvious if the gears are not mated correctly as one tooth out either creates too much free play or in the other direction holds the throttles open. There is only one position that works correctly.
Those with twin cable throttles will know how much fun it is getting that little block on the end of the cam chain connected to the two cable nipples at the same time and then the top cover replaced without one of them slipping out. I've done it a good few times now but I don't think I'm getting any better at it.
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Those with twin cable throttles will know how much fun it is getting that little block on the end of the cam chain connected to the two cable nipples at the same time and then the top cover replaced without one of them slipping out. I've done it a good few times now but I don't think I'm getting any better at it.
My 1978 R100S has the twin throttle cables. I fought 'em a couple times until I started using a simple trick.
The butterfly valve return springs create the tension problems associated with refitting both cables and getting the top back on without one or both cable ends popping out of position. Use a couple of small, wooden blocks to hold the butterfly valve in the full open position. Tension is removed from the cables and getting all the bits in their correct location is much simplified.
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The butterfly valve return springs create the tension problems associated with refitting both cables and getting the top back on without one or both cable ends popping out of position. Use a couple of small, wooden blocks to hold the butterfly valve in the full open position. Tension is removed from the cables and getting all the bits in their correct location is much simplified.
That's pretty much exactly what I did Monte except I didn't hold them fully open just used a couple of small wedges under the throttle stops. Might try something a bit thicker next time.
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The butterfly valve return springs create the tension problems associated with refitting both cables and getting the top back on without one or both cable ends popping out of position. Use a couple of small, wooden blocks to hold the butterfly valve in the full open position. Tension is removed from the cables and getting all the bits in their correct location is much simplified.
That's pretty much exactly what I did Monte except I didn't hold them fully open just used a couple of small wedges under the throttle stops. Might try something a bit thicker next time.
For those folks still reading this thread, save Barry and I, resist the urge to remove the springs on the butterfly valve's shafts. All you'll get is some cuts on your hands and a difficult refit... unless you remove the Bings. Don't do that!
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And when renovating carbs, do not forget to put new return springs (at least on the choke lever) because sometimes these are so weak the lever does not come fully back....
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Going back to the original issue which is wear on the throttle gears there maybe some benefit in fitting the after market lighter springs that are available as besides giving you a lighter throttle action the reduced load on the gears may make them last longer.
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Rather than starting a new thread to search for...
The throttle on my R65 was functional, but very heavy, notchy AND rough!!!
Changing up gear was difficult and cruising meant leaning on the bar to hold it rather than trying to pull back using the wrist all the time. Yuk.
So, cables looked OK but the inners were nasty (typical worn Bowden feeling) and the throttle gears had lumps and bumps (worn off and re-positioned metal). The gears were serviceable since they still looked like gears, so I simply filed off the high spots and re-lubed it all.
Combined with less-fierce springs (from a great shop in California!) the throttle is now (almost) how it should be. No sticking, light and responsive but I can just feel each throttle gear tooth moving to the next. Massively improved though.
Has anyone done something 'random' to replace these gears? The design is good but the materials are rubbish.
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Less fierce springs available in California??? Gee, I tried lighter springs once and they were too light. May I have the name of that California shop?
I have tried everything mentioned over the years and I still develop Popeye forearms on a long trip. Doable but could be more comfortable by being a lighter twist. No one has mentioned making sure the wee stop screw behind and below the throttle on the right hand, that is suppose to be a throttle "cruise control", is not turned up too tight to stop light throttle return movement? For those new owners, this screw can remain hidden for years!
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Was it the EZ Pull springs you tried before Sue? The guy that does those has turned the sales over to Ted Porter/Beemershop so maybe that's the California connection?
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I was prepared to buy lighter springs but at the time couldn't find them in the UK, so I very carefully stretched the original spings using a spring balance to apply increasing levels of force in measurable increments and to ensure both ended up the same. This was 10 years ago and has worked fine ever since with a noticeably lighter throttle action.
Excessively strong springs is typical of German over engineering. I had to replace the throttle spring on my 190e Mercedes for the same reason.
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Was it the EZ Pull springs you tried before Sue? The guy that does those has turned the sales over to Ted Porter/Beemershop so maybe that's the California connection?
EZ Pull springs...I think so....but they were so weak/light that nothing happened correctly BUT I would trust Ted Porter to get it right so I'll try his website. Thank you!