Help with minor running issue and noise

When riding I can hear a sort of circular rubbing noise that increases with engine speed. At first I thought it was the brakes rubbing as I hadn't been out for a couple of weeks and they initially binded on a bit. But now they don't seem to be binding at all and I think it is something else.

Also at low speed in first it feels like something is trying to hold the bike back, as if the brakes are being gently dabbed intermittently. Again though, I don't think it is the brakes.

Third, and lastly, when I pull away there is a kind of "clunk" noise after i've released the clutch, it almost sounds like the stand is flipping back up, but I know thats not it.

Any ideas would be appreciated.

[flymo]

Originally Posted by Jay1

I can hear a sort of circular rubbing noise .

What exactly is a circular rubbing noise?

[flymo]

Jay, when you are riding along find somewhere safe to do it and coast. Disengage the clutch and just let the bike freewheel along. If the bike still feels 'held back' or there is come kind of binding you can pretty much elliminate the engine and clutch from the problem.

Let us know how you get on.

LOl sorry maybe circular grinding noise isn't the best explination. it's kind of a pulsating sound, if that makes sense, not constant, but a constant rythm.

I like the coasting advice though, thanks for that, will give it a try later.

Any thoughts on the clunk as I pull away. Could any of these symptoms be to do with an old chain. I know my chain needs replacing and have the replacement, just got to get it fitted.

[flymo]

Yeah, chain adjustment and condition can make a big impact on noise but obviously difficult for me to say without hearing it.

You can check the chain in two ways, first get some gloves on if you wanna keep your hands clean and then work your way along the chain making sure that the links actually rotate around each other rather than being stuck or stiff.

Also, check the chain slack. Get sombody to sit on the bike whilst you move the chain up and down midway between the sprockets. Movement should be limited to about 25mm (1 inch) or so. If its much more than that you will certainly here noise, any tighter and you may well have damaged the chain by stressing it too much.

If it is really stiff it can be replaced but worth having a go at cleaning it. Get yourself some parafin from a local diy shop and a stiff toothbrush. A good pair of marigolds helps here too if nothing else it might get your pulse racing........moving on. Work your way along the chain and give it a good clean. Afterwards a good clean off to remove the parafin with soapy water and then lube it up with chain lube.

However, might be nothing to do with the chain!

Nice one. thanks for that mate. The chain is pretty clean. I only done it a week or 2 ago, and it is kept lubed. I know it's passed it's best though as it was flagged up as needing doing soon at the last service. Like I say I have already got the replacement.

Wasn't sure though if a chain can contribute to running noise. It would fit with the noises being made if it was a loose chain so fingers crossed thats it.

I've ran with a loose chain ... and I couldn't believe the racket! Thought the engine was about to blow up (again ) ... thankfully, I was able to gingerly ride into a local garage and ask to borrow some tools (as I was on my way home from work when I noticed it) - now I usually carry the required tools around with me