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Post Info TOPIC: timing chain


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cam chain - timing chain - problems and checking
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Good day, cant find information how to check lenght of cam chain, if anybody know , please help ! Thank you !



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RE: Cam chain checking
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The Yamaha service manual does not give a cam chain length service limit.  It states that if the clearance between a sprocket tooth and a chain roller is equal to more than 25% of the roller diameter, the chain and sprockets should be replaced. 



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timing chain
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any body know a good supplier for a timing chain for a 4gy.

thanks

keith.

 



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Super Guru

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I am not aware of anyone doing after-market cam chains so its a Yamaha OEM one you will probably need - part number 94591-43122-00

MotoWard or Fowlers of Bristol are good for mail order - should be about £20 plus carriage.

Brian



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wow thanks dont suppose you have any phone numbers do you .

keith



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Google is your friend.

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Moto Ward

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Fowlers of Bristol

If you need to contact a member of our Sales Team please give them a ring

Tel: 0117 977 0466
Out of Hours: 07973 252 435
Fax: 0117 972 5528

Opening times for all departments are available here.

For Spares Dept click here
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Bristol
BS4 3DR



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East Budleigh. Devon



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Cam chain problem???(i think)
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Raid 4GY 10000 mls. On the road at last, pulls cleanly BUT lot of what i think is cam chain  whoosh!! not rattle,apparent on acceleration,stops on deceleration. Bike has had periods of standing, could it be cam chain tensioner stuck. Im i being paranoid, do i stop riding till its correctly diagnosed. All comments most welcome. Alan



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If a cam chain is very worn then the horizontal lines on the cam gears won't line up as they should do. I have only got a photo of the gears with a good chain - sorry!

Removing_TTR_head4.jpg

If the adjuster is fully out and not taking up the cam chain slack then you would be able to feel this by pressing on the chain between the cam gears. It should be really tight - any looseness here would be bad news.

Cam chains are cheap enough but a fiddle to fit as they don't have an owner-friendly split link cry

Brian



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i have a photo from worn cam chain!!!

http://imageshack.us/photo/my-images/830/087yf.jpg/ 
scaled.php?server=830&filename=087yf.jpg&res=medium
But still the bike works Good!

Can you explain me what you mean? "not rattle,apparent on acceleration,stops on deceleration"



-- Edited by fwtian on Thursday 1st of March 2012 12:40:29 PM



-- Edited by Cubber on Thursday 1st of March 2012 01:16:48 PM

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alan wrote:

Thanks for your reply. Hard to explain, as you accelerate what i can only describe as a chain noise is very noticeable, if you feather the thorttle the noise stutters, when you close the throttle the noise stops. regards Alan


It has been known for the drive chain noise to sound like it is coming from the engine.

Check your chain is adjusted and lubed properly and that the upper roller bearing is OK and not falling apart coz that can make a racket. Also check the sprockets are aligned - usually it is sufficient that the snail cams on the rear axle are on the same spot each side.

Also check your chain slider isn't worn through which would allow the chain to make metal-to-metal contact with the swing arm bearing cap. Just an idea...

Brian 



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Thanks for your reply. Hard to explain, as you accelerate what i can only describe as a chain noise is very noticeable, if you feather the thorttle the noise stutters, when you close the throttle the noise stops. regards Alan

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Thanks Brian Checked cam chain, perfect, not a mark on the cams themselves. Will follow your suggestions and have a good look at drive chain setup. Alan S.

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timing chain
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fwtian wrote:

i have a photo from worn cam chain!!!

http://imageshack.us/photo/my-images/830/087yf.jpg/ 
scaled.php?server=830&filename=087yf.jpg&res=medium
But still the bike works Good!

Can you explain me what you mean? "not rattle,apparent on acceleration,stops on deceleration"



-- Edited by fwtian on Thursday 1st of March 2012 12:40:29 PM



-- Edited by Cubber on Thursday 1st of March 2012 01:16:48 PM


 

If the cam chain is worn it will not rattle on acceleration unless it is so worn that it is wearing the inside of the barrel....It will rattle on idle or when you let off the acceleration.

If the cam chain is rattling on acceleration your about to have some BIG problems no

Just thought i'd set that straight.








-- Edited by barra8 on Tuesday 22nd of January 2013 03:35:40 PM

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I stripped the clutch out on my 325 whilst the engine is out and it was only a few extra bolts to undo to get the timing chain off to check so I did so!

It is difficult to gauge chain wear but a simple check is to hang the old chain alongside a new one and compare their length. You can see from the pic below that the old chain at the back has stretched and is hanging lower. So I am putting in a new chain!

Not very scientific I know wink

Brian

Timing chain comparison 001.jpg



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Hi

I am new to the forum, so hello to you all.

Anyway I have been checking my valve clearances and while doing so noticed that the inside of the  cam cover had a little bit of wear, just above the cam chain. This made me have a look at the cam chain, I can move it up and down a good 15mm, between the cam gears. I had a look on this forum to get some advice and show you my picture of my cam gear alignment. My question is this, how do I know if it is the tensioner or the cam chain? or will I need to replace both?

Cheers for advice. The pictures are a bit out of focus, need a new camera as wellcrycry

Stevettr 001.JPGttr 003.JPG



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ttr steve wrote:

Hi

I am new to the forum, so hello to you all.

Anyway I have been checking my valve clearances and while doing so noticed that the inside of the  cam cover had a little bit of wear, just above the cam chain. This made me have a look at the cam chain, I can move it up and down a good 15mm, between the cam gears. I had a look on this forum to get some advice and show you my picture of my cam gear alignment. My question is this, how do I know if it is the tensioner or the cam chain? or will I need to replace both?

Cheers for advice. The pictures are a bit out of focus, need a new camera as wellcrycry

Steve


Hi Steve

If the crankshaft was definitely at TDC when you took those pics then my initial observation was that your cam chain is toast mate! Not seen one that worn before - unless the chain has jumped a tooth on the sprocket confuse  

It's not clear from the pics so can you advise - is the LH sprocket line tilted over more than the RH sprocket (indicating a worn chain) or are they exactly parallel (more likely the chain has jumped a tooth)?

Brian



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ttr steve wrote:

Hi

I am new to the forum, so hello to you all.

Anyway I have been checking my valve clearances and while doing so noticed that the inside of the  cam cover had a little bit of wear, just above the cam chain. This made me have a look at the cam chain, I can move it up and down a good 15mm, between the cam gears. I had a look on this forum to get some advice and show you my picture of my cam gear alignment. My question is this, how do I know if it is the tensioner or the cam chain? or will I need to replace both?

Cheers for advice. The pictures are a bit out of focus, need a new camera as wellcrycry

Steve


If you can push the chain down 15mm, that is way too far! Replacing the cam chain will be required.

There is no bulletproof way to check tensioners, other than making sure it winds up and releases smoothly. If in doubt, replace.

While you are there I would suggest to check the chain guides, paying attention to the sides as well as the wear limit. The cam sprockets/cogs should be replaced if too worn also.

Jarrah

 

 



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Hi Jarrah and Brian

Thanks for the advice.. Yes the tdc is correct, I checked it 3 times, it has not jumped a tooth, as if you put it back a tooth it is out the other way. The left hand one is slightly more out of line.

So I agree with both of you, a new chain is needed and I will check the tensioner.

Will the clearances on the valves change when I do this???

Or is it ok to carry on with this part of the work.

Many thanks

Steve



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Hi Steve

Replacing the timing chain won't alter the valve clearances.

Email me if you need a new chain - see http://www.totallyttrs.com/NOS/index#cam_chain

Brian



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Cheers Brian

Will send you an email, when I know what size shims I need as well.

Steve



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