My '05 has a cam chain?

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James Burleigh

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When I had a big service done in November at my local dealer, there was a little note on the service receipt that said: NOTE.....CAM CHAIN TEN. STARTING TO GET LOSE. NEEDS TEN. SOON.

This is followed by a hand-written note saying parts and labor cost as follows:

5JW-12210-01-00 ($97)

5JW-12213-00-00 ($5)

Labor $80

---------------------------------------------

Is this something I can do myself and save some moolah? What does it even mean? :blink:

JB

Mr. Goodwrench :rolleyes:

Edit: It's an '05 ABS.

 
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That estimate probably only covers replacing the tensioner, not the chain. The chain is inexpensive but requires a lot more labor because they'll have to pull off the valve cover. The time to replace the chain would be during a valve clearance check when the valve cover is already off.

The cam chain tensioner should be good for at least 100k miles, but some people have had problems with them and it could be catastrophic if it fails.

 
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A loose cam chain will affect valve timing enough that it will cost you some horsepower and a little engine efficiency. If it continues to develop slack and the cam chain tensioner doesn't ratchet enough to re-tension it again bad things can happen.

I know someone that had a loose cam chain that actually skipped some teeth on the cam chain drive sprocket. When this happened the pistons struck all eight exhaust valves, followed by striking four intake valves. It bent both cams, destroyed the cam holders and split the cylinder head. Then, before the top of the engine could be repaired the whole crank/piston/rod bottom end assembly had to come out and be inspected for damage. Expect this kind of repair to run in the $5k range. This unfortunate schmuck had this happen last fall and still doesn't have his bike back on the road today :dribble: After seeing this catastrophe I’ve become an advocate of cam chain and chain tensioner maintenance.

I'm with Ashe, change the chain, it is cheap (and inexpensive too) and wears. If you can find some way to do this in conjunction with a valve check, do it, because it chain involves the same work as an adjustment.

The cam chain is driven by a gear on the end of the crankshaft. It makes a very long run up the right side of the engine to the cylinder head. Along this long run up to the cams it passes over the cam chain tensioner and slipper which removes any slack. It loops over the intake and exhaust cam gears to drive them. This is the fundamental mechanical timing of your engine. This is what keeps the pistons and valves doing a synchronous dance. This mechanical timing allows the breath-in/breath-out; compress/power cycles to occur only at the appropriate times. It also makes sure the valves are safely pulled up into the cylinder head before the piston comes all the way up, and makes sure that the valves don’t try to open when the pistons are at top-dead-center.

 
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I know someone that had a loose cam chain that actually skipped some teeth on the cam chain drive sprocket. When this happened the pistons struck all eight exhaust valves, followed by striking four intake valves. It bent both cams, destroyed the cam holders and split the cylinder head. Then, before the top of the engine could be repaired the whole crank/piston/rod bottom end assembly had to come out and be inspected for damage. Expect this kind of repair to run in the $5k range. This unfortunate schmuck had this happen last fall and still doesn't have his bike back on the road today :dribble: After seeing this catastrophe I’ve become an advocate of cam chain and chain tensioner maintenance.
If this happened to me, the bike would turn up missing and my insurance agent would be giving me a claim #. Unlikely the motor will ever be the same again.

 
I know someone that had a loose cam chain that actually skipped some teeth on the cam chain drive sprocket. When this happened the pistons struck all eight exhaust valves, followed by striking four intake valves. It bent both cams, destroyed the cam holders and split the cylinder head. Then, before the top of the engine could be repaired the whole crank/piston/rod bottom end assembly had to come out and be inspected for damage. Expect this kind of repair to run in the $5k range. This unfortunate schmuck had this happen last fall and still doesn't have his bike back on the road today :dribble: After seeing this catastrophe I’ve become an advocate of cam chain and chain tensioner maintenance.
:(

Note to self: Add new item on my list of things to check...

 
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A loose cam chain will affect valve timing enough that it will cost you some horsepower and a little engine efficiency. If it continues to develop slack and the cam chain tensioner doesn't ratchet enough to re-tension it again bad things can happen.
I know someone that had a loose cam chain that actually skipped some teeth on the cam chain drive sprocket. When this happened the pistons struck all eight exhaust valves, followed by striking four intake valves. It bent both cams, destroyed the cam holders and split the cylinder head. Then, before the top of the engine could be repaired the whole crank/piston/rod bottom end assembly had to come out and be inspected for damage. Expect this kind of repair to run in the $5k range. This unfortunate schmuck had this happen last fall and still doesn't have his bike back on the road today :dribble: After seeing this catastrophe I’ve become an advocate of cam chain and chain tensioner maintenance.

I'm with Ashe, change the chain, it is cheap (and inexpensive too) and wears. If you can find some way to do this in conjunction with a valve check, do it, because it chain involves the same work as an adjustment.

The cam chain is driven by a gear on the end of the crankshaft. It makes a very long run up the right side of the engine to the cylinder head. Along this long run up to the cams it passes over the cam chain tensioner and slipper which removes any slack. It loops over the intake and exhaust cam gears to drive them. This is the fundamental mechanical timing of your engine. This is what keeps the pistons and valves doing a synchronous dance. This mechanical timing allows the breath-in/breath-out; compress/power cycles to occur only at the appropriate times. It also makes sure the valves are safely pulled up into the cylinder head before the piston comes all the way up, and makes sure that the valves don’t try to open when the pistons are at top-dead-center.
Gulp! :eek:

I'm guessing a fellow may need more than a screwdriver and crescent wrench for this job, so it sounds like (1) it's a job for a professional, and (2) get a move on this repair!

Thanks, all!

Jb

 
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If this happened to me, the bike would turn up missing and my insurance agent would be giving me a claim #. Unlikely the motor will ever be the same again.
I understand that this motorcycle may inexplicably stall on some Acela railroad tracks pretty soon.

 
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I know someone that had a loose cam chain that actually skipped some teeth on the cam chain drive sprocket. When this happened the pistons struck all eight exhaust valves, followed by striking four intake valves. It bent both cams, destroyed the cam holders and split the cylinder head. Then, before the top of the engine could be repaired the whole crank/piston/rod bottom end assembly had to come out and be inspected for damage. Expect this kind of repair to run in the $5k range. This unfortunate schmuck had this happen last fall and still doesn't have his bike back on the road today :dribble: After seeing this catastrophe I’ve become an advocate of cam chain and chain tensioner maintenance.
The other-side: chain-driven camshafts (especially Morse Hy-Vo type) are currently the cam-drive-mechanism of choice in America. Gone (pretty-much) are the rubber toothed-belts -- Americans can't stand the thought (and expense) of having them periodically replaced. Now, if they're aware at all of how the cams are driven?, they choose chain drive -- that, they perceive, never needs replacing.

Another option is: the much loved push-rod, rocker-arm (preferably w/hydraulic lifter) set-up -- and "You-Know-Who" promotes those.... :eek: :blink:

 
If JB is a YES man it should be covered.

If you are the schmuck without YES, Yamaha's rep told the dealer that Yamaha isn't responsible for the chain/chain tensioner on a 40k mile bike because they didn't think that failure at this mileage indicates a premature failure :censored: :argue: :angry03: The rep had even more to say but all he did was dig the hole deeper, no help at all.

 
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Mine broke but got me home(the tensioner that is)....about 2 miles, sounded terrible but I nursed it and suffered no damage. Mine was covered under YES and is quiet and reliable again. Get 'er fixed Jim !

Bobby

 
My cam chain was replaced under Y.E.S. when I thought my tensioner might have been going out. The dealer looked at everything & said the tensioner was fine but the chain was stretched. About 30,000 miles when it happened. The only cost to me was to fix the flat on the V-Star they loaned me while the work was being done.

 
JB,

Zac at Roseville Yamaha said he saw a bunch of bikes with this issue at about 42 - 45K miles. On the first couple, he did thorough inspections to make sure the sag wasn't allowing the chain to cause excess wear elsewhere, so when it was my turn, he said it was okay to ride with the issue for a little while, at least until the parts came in. IIRC, the acid test for whether it was the tensioner was to adjust the idle down to 850 - 900 RPM and just listen for the rattle. What I first noticed was my '05 was making a little more noise than usual right after cold starts, but it quieted down pretty quickly.

Fortunately, mine held on until 52K or 53K miles (bit rattly for 4 or 500 miles)- He did the cam chain under YES warranty and did the 2nd valve adjust while everything was already apart. :yahoo: Saved me some $$$. Are you close to a valve adjust interval?

RsvlFeej

 
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Is there a specified deflection range for checking cam chain wear?

I'm interested in knowing more...maybe contact a dealer about some information?

 
Is there a specified deflection range for checking cam chain wear?I'm interested in knowing more...maybe contact a dealer about some information?
Chain wear (often mis-stated as "stretch") is an accumulated wear between the pins and plates. Info may be found in shop manuals' specs. Or, the chain manufacturer may supply them (specs) -- often listed as the total length or length between a certain number of pins. If you know the size of the chain you can figure it out and go from there -- 428 chain = 1/2" pitch = 100 pitches = 50 inches. If yours measures, say, 52 inches -- probably beyond spec.?

Multiplate chains (like the FJR, and many others, use/s for timing chains) are/have been considered particularly resistant to accumulated wear as they're normally used in a clean, well lubed, environment and they're a robust chain design. Maybe MamaYama got some bad chains from a supplier?

Often, when/if a chain is worn-out (accumulated wear beyond spec) the associated parts (sprockets) need replacing too because of wear patterns caused from 'wrong length' chain.

Most people don't worry about this kind of thing anymore, ime. But, from what's been posted here on the forum -- it may be an FJR 'thing'? :unsure: :(

 
I just got the news from the service manager at the dealership; Cam Chain is loose on an 04 with 26K. Tensor to the limit. He's checking to see if my Y.E.S. warranty will cover it. I'm a little surprised that a "TOURING" Bike isn't more reliable. But at least this was discovered at an opportune moment.
 
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