Piston slap or valves?

[gt900uk]

Bikes mileage is about 66K, yes the rear cam chain is much tighter than the front so I think it's not how it should be and the rattle is definitely the chain being too loose. I guess the best course of action is to just strip the head right off and check the tensioner slider blade and replace the cam chain. Pushing on the tensioner blade manually with the CCT removed seems to sufficiently tension the chain.

[gt900uk]

Ok, new chain fitted, just need to get a cylinder head gasket to finish putting the bike back together. Chain guides looked ok however the old chain was a bit worn compared to the new. Hopefully that will account for the slack/rattle. It's a bit of a dismantling epic doing this.

20190808_163602 by Graeme Taylor, on Flickr
20190808_170439 by Graeme Taylor, on Flickr
20190808_170428 by Graeme Taylor, on Flickr

[gt900uk]

Bikes back together and seems to be running fine, replaced both cam chains, set timing and checked valve clearances, which were all fine, and the rattling noise is gone. Both chains were written in comparison to the new ones.

[R1ffR4ff]

Originally Posted by gt900uk

Bikes back together and seems to be running fine, replaced both cam chains, set timing and checked valve clearances, which were all fine, and the rattling noise is gone. Both chains were written in comparison to the new ones.

Nice one.Hope it all runs good for you

[gt900uk]

Thanks, I'll post a video of it running and it will let people hear what's normal and what's not. I should have taken one of it before, but the OP's link is the exact issue I was having.

Everyone seems to think that it's generally the tensioners that cause the issue but I don't think there is much to go wrong with the pointy tensioners, I wonder how many folk are running around with worn chains.
I actually managed to do the rear chain without taking the cylinder head off as there is just enough wiggle room/flex with the guide if your gentle. A bit of thought from Suzuki bolting the bottom of the guide in place instead of it slotting into a section of the engine could make this job so much easier.

[gt900uk]

Here is a video of the engine running nice and quiet compared to the rattle it previously had. I wish I had got a video of it before but it was exactly the same as the OP's in the video they posted.


https://youtu.be/j0U_ef8BAPY

Hopefully helpful for folk in the future and if you have the rattle get the rocker covers off and check those chains for tension.

Originally Posted by isutty5

Here's a clip I recorded of the sound of cold startup.

https://youtu.be/_FvQY8O7JdU

Proper rattle. But as I say, completely disappears when warm and sounds happy.

[R1ffR4ff]

Originally Posted by gt900uk

Here is a video of the engine running nice and quiet compared to the rattle it previously had. I wish I had got a video of it before but it was exactly the same as the OP's in the video they posted.


https://youtu.be/j0U_ef8BAPY

Hopefully helpful for folk in the future and if you have the rattle get the rocker covers off and check those chains for tension.

Sounds really smooth.Nice job