Timing Chain

[Rubi76]

Hi Guys ,

How do you know when the timing chain / tensioner needs attention ?

Is this part of a set service interval ?

Thanks

Dirk

[steve hawkins]

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.

[Bob_Roller]

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 .

[Rubi76]

I have 63000km on the bike, it gets real noisy when warm.

any special tools required to do the job ?

[Bob_Roller]

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 .

[montmil]

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.

[Adrian]

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 ..............................  

[montmil]

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

[raypond]

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

[Rubi76]

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

[Bob_Roller]

A block of soft wood (pine) and a hammer, are your tools of choice now .

[Rubi76]

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

[montmil]

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.

[Rubi76]

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.......

[montmil]

...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]