Cam chain replacement

[Ken Talbot]

Yukonman was up to Revelstoke this past weekend so we could replace the cam chain on his '78 E. With somthing in excess of 134,000 kms (83,750 miles) on the clock, it had got to the stage that the slack adjuster could no longer keep the chain tight. In fact, with the cover removed, you could feel slack in the chain where it runs across the guide (part number 7 here) between the cams. With the new and old chains placed side-by-side, and carefully aligned at one end, here is how much stretch there was:


Once the new chain was installed and the slack adjuster 'adjusted', the effect was immediate - there was no slack across the guide.

And, just in case anybody was wondering, if the rear nut from the #3 camshaft cap on the exhaust cam happens to slip out of your fingers and it falls down inside the crankcase along the chain damper assembly, you will probably find it by removing the exhaust system and the oilpan and reaching up and in with your right hand from the left side of the bike, on the forward side of the opening just to the left of the centreline of the motor. DAHIKIJD

[uk1.1s]

Camshaft nuts

Ken,

Slippery little suckers aren't they!

Bet the air was blue for a couple of minutes

I rebuilt an engine from the crank up and did this on my (makeshift) bench. As the engine was out two of us picked it up, turned it over and shook for all we were worth......... a happy result too thank goodness.

[Dennyz]

Tip:

Placing a round frig magnet inside the socket will hold on to the nut.

[Ken Talbot]

Yup, and Peter and I discussed that stuffing a shop rag over the cavity would have prevented anything falling in too. Did we put a rag over the cavity when we got around to re-assembly - you bet we didn't..

[snakedriver]

I just dropped the exact same nut down the exact same hole last night. You better believe the air was blue out in the shop. It wrecked a perfectly good night of wrenching

[IanDMacDonald]

Lmfaooo. I wonder if that nut is still in my engine. Never did find it when I pulled my pan. However, I never looked in the engine.

My question is this: has anbody replaced the camchain just to do it and never worry about it again? I'll be pulling the engine soon, and while pulled, I'll check lash and replace the cam caps, etc. Just wondering . . .

[MaximPhil]

Hi Ian,
We replaced the cam chain in Addie at 90,000 Km as the head had to come off to fix bent valves. I was advised to do so. We judge the old chain to be about 2/3 of it's useful life so 134000 Km sounds about right.
Phil

[IanDMacDonald]

Wow, my bike only has around 33k on it. I guess it's good for now.

[trbig]

Let's see.. The bike is averaging @ a thousand miles a year. Your chain will probably be fine until the year 2080 or so.. lol.

Keep fresh oil in them and they'll go a long way. I've got well over 100k miles on this one and they're rougher miles than most do, though sitting a while and starting may be rougher on them than riding lots of miles.

With the valve cover off, put your timing on the "T", then look where the cam dots line up next to the arrows on the cam caps. As the chain stretches, the chain length between the cams increases, and you'' start seeing that when the timing mark is on the "T", the cam dot on the exhaust will be forward of the cap's arrow towards the front of the motor and the intake cam dot will be past the arrow towards the back of the motor.

And yes, Ken. Anything dropped within 3 feet of the cam chain galley, it will be sucked down in.

[Ken Talbot]

Deja vue! I can't believe this thread has come back to the top! I wonder how many nuts, washers, and master links have been dropped down the cam chain gallery since 2003?

[trbig]

LOL.. Never even bothered to look at the dates. POOF!! You're now 10+ years older Ken, in the blink of an eye!

[IanDMacDonald]

I don't have to be the author of every thread when I have a question, lol. I saw this thread as relevant, and posted my question here.

[jetmechmarty]

I don't have to be the author of every thread when I have a question, lol. I saw this thread as relevant, and posted my question here.

That's what I do, too!

[James England]

Wow, my bike only has around 33k on it. I guess it's good for now.

Definitely. You have no worries on that score. Just make sure it's tensioned correctly. Have you read the auto tensioner threads? I did mine and thought it was great. Ironically, the XJR has an auto tensioner but an after-market manual tightener is available!! No ta.