So, once again, my bike is making unusual noises, and it's disturbing me again.
About three months ago, Bob Broussard was a total hero and came up and helped me replace my GS's engine with a spare he gave me for a *very* generous price. Awesome. The old motor had a counterbalancer bearing go bad for no apparent reason, in the space of about 20 minutes of riding, it just ate itself (I didnt hear the problem until the engine was toast, noisy helmet and I was going to fast).
So, end of february, I got a new motor. Started a new job, which lasted all of a week before I got axed. Yay. Needless to say, I was kinda down, and didnt ride too much for a while. From mid-march until mid-may I rode maybe 400 miles, if that.
Either way, I got a new job as a courier, on my GS. I *love* it. Pays great, and I get to be out, in the summer sun, on my bike, all day, riding around. I'm totally psyched.
Of course, I'm also doing 1000 miles week, or more.
Last wednesday, I started hearing a strange clack-clack noise coming from the engine. It was intermittent, and not very loud. I figured it was just general GS500 rattle-i-ness, and got on with my deliveries.
It was still there the next day (thursday), so I had a look see at the motor, and found out that she was quite low on oil, so I did a refill (I'd had a few long-distance high-speed runs in the past day or two, so I figure the stress had burned off some oil).
I topped her off, but the noise persists. Here are the symptoms:
1) Engine makes metallic clacky noise between 4500 and 6500 RPM.
2) Engine idles normally, makes normal power, doesnt really clack above 6500.
3) Clacking doesnt seem to be getting worse (it built up and then levelled off at its current state), but its quite loud and noticable.
4) Generally only clacks under load, I cant really replicate the problem when the bike is sitting still. It makes a *little* noise, but nowhere near as bad as when the motor is loaded and moving the bike.
5) Noise is totally dependant on engine speed, not road speed.
6) May not be related, but the engine is backfiring a bit.
Since it started, it hasnt really gotten worse... but I cant tell. It might be getting slowly worse, and I'd not be able to tell. Either way, I've done almost 600 miles since it started, and the engine is still going strong. Last time I had a bearing go out, the engine chunked within 30 miles (on full, fresh oil)... so I dont think its the same problem.
My questions are these:
1) Do the more experienced GS'rs out there think my engine is likley to die on me soon? I absolutely need it for work... I cant afford a new bike yet (Late july... hopefully, I'll be getting a VFR).
2) How exactly do I check the cam chain tensioner properly? I've been running the bike pretty hard for a few weeks, it might just be that thing sticking after some abuse.
3) Could I have toasted something by being low on oil, and its holding off now that the engine is properly lubed again? If I did damage a bearing, would it have already failed after 6 hours of continuous 8000rpm operation?
4) If its not that... any other ideas?
Bleh.
I get that same noise only if I am in too high of a gear when going uphill. I'm overloading the engine.
6) Valves. It's time for a valve adjustment (and me too).
All I can think is to check your valve clearances. Did you happen to measure them when you put the new engine in?
If you've seen my Valve Adjustment video, there's a part at the end where I start the bike up after accidentally leaving the 2.15mm test shim in one of the exhaust valve buckets (instead of the 2.55 it needed). You can hear the LOUD tick briefly until I shut the bike off. I'm just wondering if this is the sound you're hearing. :dunno:
On your second set -
2) Best thing to do is to see how far it is out. You may need a second set of hands to do this, but here goes: before loosening the bolts to remove the tensioner (after you've set the motor to TDC on the #1 piston), use a screwdriver to hold the spring so it does not relax and fully extend on you, because then you will not know how far it has extended in the motor (and the farther it has extended, the more worn the camchain is, but if it still has tension the chain is still good for a little while more (I don't know how much :roll: )).
3) Probably. Keep checking your oil every week.
And how do I find TDC on number one, again? *sigh* :-p