Bandits and cam chain rattles

[chrisw]

I've had my 600 for a couple of years now, although I haven't used it for year now and it's been up for sale since then (with next to no interest ).

I adjusted the valve clearences not long ago (~3k miles) and most were either in or very very slightly out of tollerance.

The reason I adjusted them was because it had developed a rattle on idle, and driving a Mini and Landrover at the time, took it as needing it's clearances checked.

Checked them, adjusted and there was little difference. I'm pretty sure the noise put off an (inexperianced) buyer who assumed it needed a new cam chain (the bike now has 12k on the clock, so shouldn't need one for long time yet).

Is there anything that can be done to either reduce or eliminate the noise? I'm just going through and checking the clearences again, just to make sure. I've heard a new tensioner spring often helps? Is there anything else I should look at?

As an 'off-the-wall' thought, does the 'pair' valve ever start to make noises on Bandits?

[Tim..]

Sometimes on the old suzuki oil burners they develop a cam chain rattle due to a 'stiff' auto tensioner. A few times I have also found the tensioner can be right on the edge of clicking onto the next ratchet and after a long 'enthusiastic' ride a noisy engine suddenly quietens up.

If you decide to remove the tensioner for inspection/rebuild remember that the cam chain could come off the crank gear and everything would need timing up again. I'm not trying to scare you off taking the tensioner out but I would advise you check the timing just incase the chain skips a tooth.

Tim
____________________
Project builds: My VFR400 nc30 build thread + Honda Britain Rep VFR + What? Another VFR +Project 'cos I want one' + V8 coffee table
www.marshallracing.co.uk
OCD - Helping to bring the standard of my bikes up and make me slowly go mad since 1999

[chrisw]

[0l0dom0l0]

I will explain this one to you:

The cam chain is under a massive amount of tension. As the tensioner moves further out, the spring is less compressed and often gets stuck (like yours has) between teeth.

There are a few things you can do.

Don't be scared of taking the tensioner out which you have already done. Don't however turn the engine over ATALL when the tensioner is out, as you might cause the timing chain to skip a tooth at either the top or the bottom end. When its out you need to reset it, by clicking the ratchet all the way in again. Then get a spanner and turn the engine over by the generator or w/e slowly. You will hear the ratchet click and re-adjust itself. It may take up the extra slack and stop the rattle, it might not. Start the bike after and you will know.

If it has worked, then its all sorted, job done. If not, there are a couple of other tricks to try. Put the bike in gear with the engine off, let the clutch out, and rock the bike. Sometimes this encourages the tensioner to take up the extra slack.

If that fails then the last resort is to manually adjust the automatic tensioner. To do this, leave the spring and nut that tensions the spring in place, but undo the two bolts that hold the tensioner in place. Very very slowly undo them until you hear it click once. After it has clicked once, do them straight back up again. That way you have taken the extra space up.

If you haven't got a haynes manual I would suggest you get one and read about the tensioner and that. They are very helpful!!

Hope that helps.

Oh btw, how much were you asking for the Bike?

[chrisw]

The Suzuki manual is as detailed as needed or so I found, using it I have never found wanting for any information. I have a fair collection of Haynes manuals and tend to only use them for torque figures and tightening patterns (head bolts etc..) these days.

When I put the ratchet back in I pushed it in to take the slack and span the engine (with a spanner) while keeping pressure on it, this is what made me feel like it was just a fraction off the next click.

Interesting idea, forcing the ratchet out a step with the housing loose. My only concern with this would be excess wear on the tensioner 'plate' (for want of a better word). Have you done this yourself?

We are asking £1500 for it at the moment (no MOT or tax), or ~£1900 with both (It's 2004 K4).

[Bezzer]

[0l0dom0l0]

You won't create excess wear on the tensioner because its just a ratchet system, there is nothing to wear. The other end of the ratchet pushes on a rubber guide plate for the cam chain.

I haven't tried the technique myself, but it was recommended to me by a Yamaha mechanic. When rebuilding the engine on my Fazer, I was worried about over tightening the cam chain. He basically said its almost impossible for the automatic tensionsers to over tighten one.

He then went on to say that any bikes they had that came in with rattly cam chains, they used the technique I described to just take up the slack.

The only time it becomes a problem is if it clicks twice. That would then be over tightening the chain.

The system works like this:

https://i1183.photobucket.com/albums/x474/0l0dom0l0/Camchain.jpg

Hope that helps.

Also can you PM me with more info on the bike? Maybe a could of pics too? I have been looking for a replacement bike since my Fazer got written off. Ideally I wanted another Fazer, but it seems like your asking a fair price judging by mileage and year!

[Bezzer]

[0l0dom0l0]

Alright calm down. You don't need to be so aggressive.

It won't create excess wear on the follower because the chain is now correctly tensioned. So that's irrelevant.

It won't over tighten the chain because the chain is loose in the first place. That's why its rattling. Its also not a 'bodge'. Its a known fact that the automatic tensioners get stuck between teeth, like in this case. As long as it isn't moved more than 1 click its just allowing it to select the next level and taking the chain to its correct tension.

Replacing the tensioner springs isn't a bad idea.

Also with your comment on the mechanics, that's a load of rubbish tbh. A bike that's done less than 80K miles shouldn't need the cam chain doing. I think I'd be questioning if I took a bike into the dealer and they told me it needed a new cam chain after 12K miles. So its not a way to make a quick profit. It will more than likely cure the problem. If it doesn't, then the next step is a new tensioner.

[Bezzer]

[temeluchus]

Camchains on these motors are generally fine until 60K or so, the tensioners can become problematic at half that. As mentioned the springs often need replacing. One can also fit a manual tensioner, which can also give a vagie indication of the wear in the camchain.
____________________
Some shite cruiser. Now with guns and FREEDOM!

[Suntan Sid]

AFAIK, Suzuki automatic cam chain tensioners’ are notoriously crap.
Fit a manual cam chain tensioner, and then forget about it.
They are relatively cheap and there are loads on Ebay.
Fitting is easy, have a look at this link, it’s not specifically for your bike but the principles are exactly the same:-

https://www.thumpertalk.com/forum/showthread.php?t=639008&garpg=1

I’ve fitted one on my DRZ it took ten minutes, never had any problems with it since!