The New And Improved Unofficial R65 Forum V2
Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: Rubi76 on February 10, 2012, 07:32:28 AM
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Hi Guys ,
How do you know when the timing chain / tensioner needs attention ?
Is this part of a set service interval ?
Thanks
Dirk
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It starts to get noisy and rattly.
I changed the one of my Cafe racer when I rebuilt it at 94,000 miles. I think they should be changed earlier. But it probably was the original - if the rest of the bike was anything to go by.
Not a difficult job as long as you dont start dropping things inside the engine case. If you are in there investigating the tensioner I would change the chain anyway - they are not expensive and they are sold as kits.
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How many km/miles do you have on the bike ?
One thing that I have heard other members say, that a low idle speed is not great for the cam chain area .
I think the owners manual states an idle speed of 850 rpm, due to hearing loss from working around jet aircraft for the last 36 years, I have my idle set at 1200 rpm, so I can hear it .
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I have 63000km on the bike, it gets real noisy when warm.
any special tools required to do the job ?
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The exhaust system needs to come off, you can't get the engine cover that's over the timing chain area off with the exhaust system on, so you need the tool that goes on the exhaust nuts .
You also need a removal tool for the alternator rotor .
Other than that, just common hand tools .
Motobins has a complete kit available for this, quite reasonably priced as well .
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If you do decide to replace the timing chain and guides and the etc's... save yourself some anguish before removing the chain.
The timing mark on the lower sprocket -a dimple usually- is readily visible. The tiny, little, scratch of a timing mark on the smaller, crankshaft sprocket is invisible with the nose bearing in place. So...
Remove the spark plugs and bring the engine to Top Dead center (TDC). Double check you are at TDC. The lower sprocket's dimple should be exactly at 12 o'clock, high noon. Clean off the teeth on the upper sprocket and use white paint to identify the tooth at the 6 o'clock position. After that chore, everything else is cake.
Be advised, if you get the top sprocket just one tooth off, there's a very good chance a valve will marry up with a piston top. D'oh!
Visit the Coppermine Photo gallery and see my photo essay on timing chain replacement.
Motobins has the best deal on the replacement kit. I bought from them and glad I did. They even include the two coin-sized gaskets that many folks don't even know about.
http://www.motobins.co.uk
The timing chain kit is specific to the R45 & R65-Part #10160. Motobins also has the Rotor Extractor tool you'll need-Part #99700. One stop shopping.
BTW, my '81 R65 began to make a terrible ruckus after rolling off the throttle and coasting down to a stop. Noise went away under acceleration. My vintage n' sloppy timing chain had worn through the plastic tensioner "shoe" and was grinding the chain's side plates against the metal substrate. Tension spring had also collapsed several mike mikes. Replaced all. All good now.
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Visit the Coppermine Photo gallery and see my photo essay on timing chain replacement.
Thank you for these photos and your explanations Montmil. My R65 is 1984 and has electronic ignition but I assume the only difference is a bean can versus elct ign can. Good advice all round and it's nice to see "real world" pictures and read your experiences. For armed is forwarned is it not???? Adrian .............................. ;)
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Adrian, as of the 1981 model year, all Airheads have an "electronic" bean can fitted with the Hall sensor rather than ignition points. The exterior of the ITU looks almost identical to the older version.
Some owners have even removed the Hall sensor and retro-installed points, as they are easier to repair on the road... so sayeth the "pointy" ones.
Monte
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G'day Dirk,
I did mine on an '86 R65 yesterday. Good advice from the others already. I already had my exhaust off but I'm not sure that it is essential, just much easier. You don't need the "special tool" to extract the rotor. A 2" length of rod and an 8mm bolt will do it. See here: http://www.airheads.org/content/view/194/98/
Getting the split-link in will be much easier if you have a pair of tweezers or forceps or haemosats with a bent end.
Snowbum's advice is good about putting the old link half in from the front to hold the chain while you get the new one in from the rear. He says to block the holes to the crankcase with rags but I found that some heavy plastic works better - it doesn't get in the way as much and can be pushed backwards into the hole (the one at 7 0'clock) to give you more space. I just used a jiffy bag.
Remember to make sure you know where all the wires go, and make sure that all the ones that pass through the rear grommet on the timing case are in place before you bolt it all up again. It's really tedious to have to undo all the bolts and do them up again just to replace one wire. Trust me on this.
There's lots of good info on the net. Have fun.
Cheers
Ray
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Hi Guys,
Thanks for all the very useful info.
Not having much luck so far.
I cut off both the exhaust nuts and now I can not seem to get the header pipes free. they are stuck solid.
The left pipe looks like it moves a little bit but the right one aint budging.
Any tips ?
Thanks
Dirk
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A block of soft wood (pine) and a hammer, are your tools of choice now .
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Hi Bob,
It looks like the PO also had a go at trying to get them off. I did try the wood and hammer but did not get too rough in fear of damaging the pipes.
I have sprayed a little bit of oil in between to "soak" over night
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You don't need the "special tool" to extract the rotor. A 2" length of rod and an 8mm bolt will do it. See here: http://www.airheads.org/content/view/194/98/
This technique has actually worked for some. Others have come to grief when the short length of rod mushrooms or bends under pressure and locks itself into the crankshaft's snout. D'oh, now what! Note that the BMW-specified tool threads into the crank's snout whereas the hardware bit has the un-threaded rod pushed down into the crankshaft. I think it was Bob Roller that cautioned folks to be prepared to catch the rotor as it pops off. Lots of pressure being generated -wear your catcher's mitt.
How do you know if the hardware store design will work or ruin your crankshaft? You don't. The 5-6 bucks spent for the rotor removal tool is w-a-y cheaper than tossing a crankshaft.
If you have removed the rotor before, the two-part tool might be trustworthy. Do you feel lucky? As a first timer handling the timing chain job, I'd recommend stacking the odds in your favor. [smiley=2cents.gif]
As to the stubborn header pipes... Have you loosened up and/or removed the mufflers and loosened the clamps securing the headers to the frame? Get ya some wiggle room going and they will come away. Try a penetrant, such as PB Blaster, rather than plain oil and then try again; tapping the pipe in a direction that would parallel the pipe-to-head alignment.
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Thanks for the heads up Monte.
The way my luck has been going lately I won't try the Hardware method to remove the rotor.
I have loosened all the clamps and mufflers on the bike but that right header pipe is holding on tight.......
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...I have loosened all the clamps and mufflers on the bike but that right header pipe is holding on tight...
1. PB Blaster and overnight soak, [smiley=bath.gif]
2. Make rude references about the bike's bovine mother, [smiley=cowsleep.gif]
3. Liberal application of a couple adult beverages, [smiley=beerchug.gif]
4. [smiley=smash.gif]
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[smiley=grin.gif] [smiley=dankk2.gif]
...I have loosened all the clamps and mufflers on the bike but that right header pipe is holding on tight...
1. PB Blaster and overnight soak, [smiley=bath.gif]
2. Make rude references about the bike's bovine mother, [smiley=cowsleep.gif]
3. Liberal application of a couple adult beverages, [smiley=beerchug.gif]
4. [smiley=smash.gif]
[smiley=grin.gif]
[smiley=dankk2.gif] I will closely follow this step by step guide
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I use a rubber mallet to tap (or whack) the header pipe from inside the bend to force it forward. They can bind if one side has moved more than the other, so tap them back in and start over. You got one to move, so tap it back in and tap on the other side.
These dual crossover headers are a super pain to install and remove. I don't care if they produce more hp, I think I'll get rid of both crossovers and make it loads easier!
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These dual crossover headers are a super pain to install and remove. I don't care if they produce more hp, I think I'll get rid of both crossovers and make it loads easier!
Gotta agree with you there, 'Spokes. The dual X-overs on my '81s headers are permanently married; ain't no divorce in their future. Should I ever get a wild hair and buy new header tubes, they will be minus the cross-overs; even if those stubs have to be capped off.
When I did the timing chain refurb, I removed the headers and cross-overs as a single unit. The center stand had to be up, then down, then up, then... sorta like a BMW Rubics Cube, but it's doable. PITA, but doable.
Monte
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When I did the timing chain refurb, I removed the headers and cross-overs as a single unit. The center stand had to be up, then down, then up, then... sorta like a BMW Rubics Cube, but it's doable. PITA, but doable.
LOL ;D
My same exact feelings! Ditch the damn things, they're not worth the trouble!
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2 hours of hammering away [smiley=smash.gif] and nada, Right side header aint budging.
The left header is loose, how exactly does the darn thing get so tight ?
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Anyone have an objection to and/or other thoughts on the application of some heat?
Use a propane torch to caress the area of the cylinder head around the exhaust port? Heat the cylinder head enough to get some aluminum expansion...
This issue gets stranger and strangerer :-/
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Hi Monte,
I am taking the Bike to someone to get the pipes off and open the timing chest. This is taking way to much time for what should be a fairly straight forward repair.
I will update as soon as the pipes have been separated from the head.
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Sounds like a plan. [smiley=thumbsup.gif]
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The first time I removed the header pipes to replace the timing chain, I had a difficult time getting the pipes out of the head .
When they finally did come out, the pipes 'sprang' outwards and if you got one pipe lined up with the hole in the head, the other pipe was about .50 inches (13mm) from being lined up with the other head .
I had to take the crossover pipes apart to get the exhaust system back on the bike .
If and or when you get the pipes apart, a liberal coating of anti-seize compound on the mating joints, will make it easier to get them apart again if needed .
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:D do we really need those cross over pipes ?
I see the cross over pipe at the back is cracked and the left hand side where it goes into the muffler is starting to rust through. Might have to see if I can get that one replaced. So far spending more time working on the bike then riding it :(
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There are conflicting ideas on those crossovers. One camp says they help low-end power, the other says they're only there for noise reduction. I tend to agree with the latter, and have never seen a dyno graph proving the former. I had an R1100S with the crossover removed and noticed no difference in low end power, and that bike is geared fairly tall so you think I'd notice.
I have noticed a more definite and emphatic exhaust note when crossovers are removed. I have an 84 R100 that came with the dual crossover headers and hated it so much I cut off the rear and welded them smooth. Even if those crossovers aren't rusty and sealed tight together, they can be a bitch to separate. So usually, once they're together, they stay together and eventually the only way to separate the headers is to sever the crossovers.
I've been wanting to perform a xoverectomy on the LS for some time now. But the headers are in good enough shape I hate to hack them up (am I sounding goofy or what???) so am waiting for either a set of early headers or cheap dual xovers to modify.
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There are conflicting ideas on those crossovers.
Hi guys - this is very interesting cos I'm also sick of fiddling with the total system to get it on and off. Although mine come apart easy enough once off - I still hate the faffing around to get the whole system back on. So, if I understand the posts, I could find a wat to seal of the tubes where the crossovers go - probably a plug that I can clamp on maybe - and the bike will run okay. I'm in the niddle of a restoration so I going to have to re tune the carbs and wotnot. My pipes are the StainTune system for the R65 - mines a 1984 twin rear shock.
Thanks for any comments and further help - Adrian .....................
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Just plugging the crossover (in front anyway) would look wonky, but you could experiment by doing just that. Then if you decide to go with it, you've got perfect pipes to modify. A good welder can cut off the stubs and use the bits to weld up the holes. A good job, once smoothed and polished would be invisible.
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thanks Wirespokes - I'm so fed up with the awkward and diifcult process - I shall get this done when I have some other minor welding done - thanks again for such useful advice. Adrian ....................
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Finally the Exhaust if free - all it needed was a really,really big hammer and some choice words !
Looks like the exhaust had a little bit of a ding put in it that made it twist slightly.
Anyway managed to get it off with the xover pipes attached and intact as a whole and lowered it down to the ground and completed the twisty dance to get it past the center stand.
Now to pop open that timing chest....
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[smiley=clap.gif] Rubi76 rocks... or at least, hammers. [smiley=furious3.gif] works every time.
After all your trials n' tribulations with the exhaust, the timing chain ought to be cake. Luck to ya.
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1 x home made rotor puller. Made from a High tensile bolt then trimmed to fit , worked like a charm.
(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fwww.suraklyn.com%2Fr65_forum_gallery%2Falbums%2Fuserpics%2F13122%2FPuller.JPG&hash=ff935f65f5720651ae0c106b39cf8270505b0a19)
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Other than the double nut, it's the same as the OEM tool .
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Hi Guys ,
The Tensioners for timing chain.
The chain tensioner looks worn out but the slide rail still looks ok. Should I replace the slide rail ?
(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fwww.suraklyn.com%2Fr65_forum_gallery%2Falbums%2Fuserpics%2F13122%2Fnormal_tensioner1.jpg&hash=cf66c6ce95ee31b34e7ba5943f3c5a87d639100c)
(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fwww.suraklyn.com%2Fr65_forum_gallery%2Falbums%2Fuserpics%2F13122%2Fnormal_tensioner_2.jpg&hash=c8c3695bc3b990a8148b02ff08731a9d056e8b65)
(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fwww.suraklyn.com%2Fr65_forum_gallery%2Falbums%2Fuserpics%2F13122%2Fnormal_SDC11957.JPG&hash=85cb0c5eeb49459ea2430395bcf452d80869edf1)
Thank goodness there is a master link on the timing chain
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Replace both the slide rail and chain tensioner. They are not expensive. Also, be sure to replace the coil spring behind the tensioner piston. The spring can lose tension over the years, reducing the proper pressure exerted on the chain -as mine had done on the '81. Another low priced bit.
I see the dimple in the cam sprocket. Clean it off and dab some white paint in it. Pull the spark plugs and rotate the engine to TDC on the right-side cylinder. Confirm and double check. The dimple should now be at high noon, 12 o'clock.
You may be able to spot the tiny, scratch of an alignment mark on the crankshaft sprocket; maybe not. Small inspection mirror and flashlight. Clean and paint the tooth at the 6 o'clock position -directly opposite the dimple.
Now you can remove the chain with the confidence that you'll be able to set the cam timing correctly during reassembly.
Poke some shop towels in those crankcase openings.
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Will do !
Thanks Monte ;)
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Just did the timing rail, guide, and spring following Monte's directions to the "T"! [smiley=beerchug.gif]
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When you replace the fixed slide rail I was told that it should depress the chain 1mm. I couldn't find that written anywhere...
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When you replace the fixed slide rail I was told that it should depress the chain 1mm. I couldn't find that written anywhere...
Hmmm... Told by whom?
When you consider using the guide rail to depress the chain, this will only result in rapid wear of the guide and a greater dependency on the operation of the chain tensioning system. Under operation, the guide rail side of the chain is under load and being pulled in a straight line between the cam and crank gears. The guide is positioned parallel to the chain with perhaps a very slight 'kiss', no more, as no tensioning is required on this side of the chain; the running engine is doing it for you.
The "unloaded" portion of the chain will have a bit of slack taken out by the pressure exerted by the tensioner spring against the chain tensioner shoe.
I did substantial due diligence through multiple websites and Airhead gurus prior to replacing the timing chain. The chain guide should be positioned in a way that does not depress the chain's run as this will lead to rapid guide wear.
As seen in Rubi76's photos, there was practically zero wear on his guide rail as it was correctly aligned. His tension shoe was almost worn through to metal.
Also, please note that both the Clymer and Haynes manuals clearly state that the guide rail is to be installed parallel to the timing chain.