When should the timing chain be replaced

[mrclubike]

Trying to avoid the situation Bob Roller got into.
My R65 has 45000 miles on it.
I guess I should replace the timing chain on it.
Only 80.00$ US delivered from Motobins and 115.00US from Dealer  is cheap insurance.
Is the quality good from Motbins. I have had good luck with non OEM parts for my Landrover out of England.
Thanks

[Bob_Roller]

The timing chain does not appear to be a part that fails regularly .
My '84 LS, has 93,000 miles on the original chain .
The chain in my '81 R65, had an odd failure, a pin on the master link sheared in the groove for the retainer clip, first time I've ever heard of a failure like that .

[Tony Smith]

Although Bob's failure is a new one on me my understanding is that timing chains should be replaced at 50,000km or about 30,000 miles.  This is not something I am all that familiar with as the older duplex chain fitted to everything prior to 1981 (but never to the R65) is pretty much a "life of engine" part unless something fails.
 
The giveaway that your chain is worn past the wear limit is a "ghosted" timing mark when you are setting timing. The reason you should replace the timing chain regularly is that it is a cheap and easy job, replacing crank and cam sprockets is expensive, and in the case of the crank, a bear of a job requiring tools not found in most home mechanic's kit. Also, if you have to replace the crank sprocket you also have to replace the "outrigger" crank ball bearing. It is admittedly only a $20 part, but it all adds up.
 
I am in the situation with my wife's bike where the chain has been let go far too long and the only thing that brought my attention to it was the double image of the timing mark when setting the timing with a strobe. My research tells me that a chain worn to that extent will have also worn out the crank sprocket and probably the cam sprocket.

Putting a new chain on worn sprockets is a waste of time as all you do is accelerate the wear on the sprockets and ruin a new chain. anyone who has ever had anything to do with chain drive bikes, even bicycles, knows this all too well.

The timing chain kit is on special  at motobins presently GBP42.00
 
The camshaft  sprocket is GBP 34.00
Camshaft woodruff key GBP 1.15
Crankshaft Sprocket GBP25.50
Crankshaft outrigger bearing GBP8.50

So, instead of GBP42.00 and a couple of hours to change the chain I am going to be spending GBP111.15 to replace parts I have needlessly allowed to wear out.

Bob in particular is probably not going to like me saying this, but replacing the chain only on a high-mileage installation is both false economy and a waste of time if you are keeping the bike because you get to do the job properly pretty soon anyway.

I am dreading the crank sprocket because I have actually changed one a long time ago (Duplex) and they are a bear to get off requiring a lot of heat and a very good puller, and you get to sacrifice the outrigger bearing on the way in as you cannot pull it off without damaging it.

Putting the crank sprocket on you cannot use more than very gentle "persuasion" so you need to heat the spocket to just short of red heat in order to fit it.

As I said, neither a pleasant or indeed "risk free" job.


i will post photos of my progress/success/failure on the R80 this weekend.

[clonmore1]

Why is it you guys always quote Motobins?

Are Motorworks not competitive against Motobins or is it just habit?

I have no association in any way with Motorworks other than I live about three miles away and see the guys riding to work on their airheads.

They are a group of bikers as well as a business, not sure if Motobins are the same

Just curious...

[Barry]

Why is it you guys always quote Motobins?

Are Motorworks not competitive against Motobins or is it just habit?

I have no association in any way with Motorworks other than I live about three miles away and see the guys riding to work on their airheads.

They are a group of bikers as well as a business, not sure if Motobins are the same
 

The main reason will be because Motorworks didn't export to the US until relatively recently. The other reason might be every time I've checked part prices Motorworks have been more expensive.

I think at least some of the Motobins staff are bikers too.  

The 3rd UK supplier worth checking out is James Sherlock and I believe they also deliver overseas. https://www.james-sherlock.co.uk/

[steve hawkins]

I have used them all.  I have found that Motorworks has been my favourite for some years, often for price.  Followed by motobins.  Then JS.  But often it is parts availability the forces the issues.

JS can be quite short with people if you ask a stupid question, which always raises a smile......

Rev Light

[Lucky_Lou]

Chatting to some "Airheads" at Squires last weekend one of the guys told me that Motorworks had been stopped from buying OEM parts direct from BMW, don't know if it is true but if it is it may force their prices up.
I have never had a timing chain go on any bike car or van I have owned so never bothered changing them, some of my Fords have had space ship miles on them, My last Transit which I bought new did 180,000 miles before I replaced it, I did change the timing belt (fabric) on my Honda when it hit 100,000 but only because I expect to get another 100,000 out of it.
Lou (Tight Yorkshire man)

[marcmax]

When I bought my LS you could hear the rattle of the timing chain through the cover. Bought all the parts and when I opened it up found the chain guide/tensioner worn away to almost nothing. It was allowing the timing chain to flop around but still had enough left to keep the chain in place. The chain itself still looked good. I suspect someone in the past had replaced it and botched the replacement of the guide/tensioner. Since I already had the parts I just replaced everything and haven't heard it since then.

[montmil]

My '81 R65 was making timing chain racket during off-throttle deceleration. A mechanic's stethoscope, or a long screwdriver, confirmed the racket was coming from the timing chain case. As the 65's odo was tango uniform when I acquired the bike, I ordered up the full timing chain replacement "kit" from Motobins. Check their site for a description and pic of everything included. I'm glad I did as I would have missed several needed items... as perhaps marcmax's PO did.

After getting into the timing chest, I discovered the racket was due to the chain wearing through the plastic tensioner shoe and rattling against the metal subsurface. But since I was in there...

The chain and sprockets were in fine fettle so I did not change out the sprockets, just the chain. Everything else was replaced with new. This chore was done a few years ago and it's been quiet ever since.

I have a timing chain replacement photo essay in the forum's Photo Gallery that you may find helpful. To access the gallery, you may likely need the double-secret password from an administrator as spamers once hit us. Send a PM to Justin for access.

As to shopping with Motobins, I am a multi-year satisfied customer. My orders arrive as fast or faster than those from US dealers such as Max BMW and Bob's BMW; although these guys also get some of my money.

Evidently the Motorworks bunch decided they wanted some of the USA trade but after so many years of saying, "No, we don't ship to the Colonies," I decided not to 'ship' any of my money to them. I think that's a fair trade off for their attitude and trade practices.

[Luca]

When should I replace the timing chain?

When your timing marks start to significantly separate.  Bob's chain was an extreme outlier.  They usually give plenty of warning before things go bad with ghosted timing marks or chain clatter.

Some chains live a short life, some last a long time.  Plenty of things can affect chain life:  oil quality and change intervals (remember, more frequently under extreme operating conditions), time spent idling, idle speed, average cruising rpm, average time spent accelerating/decelerating, and probably variations in the quality of the parts.

If I can possibly (and safely) get 100K+ miles out of my timing gear, I'll go for the chance.  By the time you've changed 3 or 4 chains you could have spent less time and money and just changed everything once when it was fully worn out.

[Barry]

At under 21,000 miles I have no timing chain problems so I've never been in there on this bike but I've read that the tensioner can be modified for better performance and longer life.

It's suggested that the tensioner blade doesn't bear on the centre of the slack part of the chain between the sprockets and as the tensioner blade wears the contact point moves even further upwards towards the crankshaft sprocket which limits it's travel even though the chain is not yet worn beyond service limits. That does sound like it might echo some of the experiences above.

Anyone who has replaced the tensioner care to comment on that ?

[Tony Smith]

Why is it you guys always quote Motobins?

Been using them since the early 80s - their delivered price to Australia has allways been consistently better than anyone else.

[mrclubike]

I have  found that small light parts for Landrover and British Bicycles    can be shipped out of England to the US at a very reasonable cost and save money  
But when it gets large and heavy it gets expensive.
Motobins web sight looks to be fairly well put together.  
I ordered some stuff earlier this week from them just to find out how fast it will come.

[Bob_Roller]

My  order took 8 days from when it was shipped by Moto-bins to Phoenix .
It arrived in Los Angeles on Monday took until today to go 400 miles to  Phoenix .

I took a better look at the blade chain tensioner that is pushed on by a spring loaded piston, it looks like it needed replacement, this is the original part with 88,000 miles on it .
It may last another 10,000 miles or so, but then it would be worn to the point that there would be metal contact with the chain, if the rubber didn't break away from being too thin to do it's job first .

So, to answer the question, I would say at 80,000 miles, if you are not having any timing  mark blurring beforehand, I would go in there and replace the two tensioners and the chain .
I'd also do a 'topend' seal replacement while you're at it, only 6 nuts and the cylinder / head comes off .
Do a compression check before as well, my '81 R65 has 131 and 135 psi compression on both cylinders, so I ordered two sets of piston rings and will replace those as well .

[clonmore1]

My engine was returned to a 'zero' hours unit earlier this year using parts from Motorworks.

Cheaper, faster, easier to ask questions (lots of stupid question too ).

I also find their website easier to navigate.

I have heard good reports from others for James Sherlock, haven't used them yet.