F650 GS wired engine noise going uphill
Got a slowly growing problem that I'd like to fix prior to riding through Kazakhstan....
It's been slowly getting worse over the past 2000 miles or so.... you know that noise old cars make when tryig to pull off in too high a gear? A sort of metallic ratteling or pinging.
My bike started doing this when I am goig uphill. First only in the high gears, when it was quite low rps for the speed I was going and the gradient of hill I was going up. So just selecting a lower gear did the trick.
But now it seems to get worse and its as if the bike just doesn't have the power to go up normal hills at normal speeds. It always makes that horrid noise when it struggles and sometines even 1st gear isn't low enough!
(I know it should go up those hills at those speeds just fine, because it used to, and because Aidan's exact same bike is doing it fine, without nises.)
So at first we thought valve clearaces? No, just checked, they are fine.
The chain tensiones also seems to be working fine and pushes in ess than 9mm (the allowed limit), so as far as I know the camchain is tight enough. It also looks undamaged.
I thought maybe the clutch plates were gone, hence the loss of power. But I am told that wouldn't cause any noises, the bike just struggles to pull. Is that true?
I am at a loss as to what the problem could be ad what to check. Any ideas would be much appreciated!