Havoc Posted January 7, 2016 Share Posted January 7, 2016 Morning gentle folk. I have suddenly developed a whine that rises and falls with the revs so in front of the gear box in the drive chain. Sounds a bit like my Pan when I first got it new, a bit sewing machiney. The motor is being pulled for a rebuild shortly but I need the old girl for transport for the next couple of months. Has anyone experienced such a noise before a catastrophic engine failure? Quite high mileage 60+K miles, sounds like it's coming from the top end to me.... Ideas? Quote Link to comment
vizman Posted January 7, 2016 Share Posted January 7, 2016 the dudettes slabby did that tom, sounded like she was running glimmer belts on a supercharger...... I think it was the output shaft bearing....I took it to loopies [after several months of ignoring impending doom] Quote Link to comment
vizman Posted January 7, 2016 Share Posted January 7, 2016 or you could check to see if your renthal bar pad is fitted correctly 2 Quote Link to comment
Havoc Posted January 7, 2016 Author Share Posted January 7, 2016 12 minutes ago, vizman said: the dudettes slabby did that tom, sounded like she was running glimmer belts on a supercharger...... I think it was the output shaft bearing....I took it to loopies [after several months of ignoring impending doom] Definitely sounds like a bearing, goes with engine speed though not m'cycle speed so before gear box, what do these cranks run on? Shells, balls or roller? 1 Quote Link to comment
vizman Posted January 7, 2016 Share Posted January 7, 2016 yeah you'll notice it more with engine speed as apposed to road speed as the bearing will be under load...that's what threw me at first, I'm not saying it's defiantly your output shaft bearing......but that's what it sounds like 2 Quote Link to comment
Jonboy Posted January 7, 2016 Share Posted January 7, 2016 1 hour ago, Havoc said: Definitely sounds like a bearing, goes with engine speed though not m'cycle speed so before gear box, what do these cranks run on? Shells, balls or roller? Its a roller crank, big burly bearings they are too.......I is with Vizman on this output shaft bearing is the usual suspect Quote Link to comment
Mr farty Posted January 7, 2016 Share Posted January 7, 2016 59 minutes ago, Jonboy said: Its a roller crank, big burly bearings they are too.......I is with Vizman on this output shaft bearing is the usual suspect Plus 1 for the output shaft bearing. GSX crank roller bearings are pretty tough. Do you know the origin and age of your engine internals? Quote Link to comment
Havoc Posted January 7, 2016 Author Share Posted January 7, 2016 Yeah OK, but this whine rises in volume and pitch when the revs rise, in neutral, at a stand still, with me stood on the other side of the road and somebody else working the twisty thing. We all call the shaft out the gear box the front sprocket is on, the output shaft yeah? Quote Link to comment
Havoc Posted January 7, 2016 Author Share Posted January 7, 2016 But that's not moving? How can it be making a noise? Quote Link to comment
vizman Posted January 7, 2016 Share Posted January 7, 2016 maybe its your van wheel bearings trying to throw you off...... 1 Quote Link to comment
Havoc Posted January 7, 2016 Author Share Posted January 7, 2016 I wouldn't put it past it, sneaky german wobbly wheeled emissions cheat. I'm trying to imagine what would make this kind of sewing machine noise, cam chain running over metal (if the rubber's really worn on the tensioner blade? It did do 60 ish miles with a slightly over tensioned cam chain. I'll whip the rocker off tonight see if anything jumps out and smacks me in the face........ 1 Quote Link to comment
gsx Posted January 7, 2016 Share Posted January 7, 2016 My money's on the cam chain tensioner sticking . . . Quote Link to comment
vizman Posted January 7, 2016 Share Posted January 7, 2016 ....could be that, especially on toms bike..... Quote Link to comment
gsx Posted January 7, 2016 Share Posted January 7, 2016 . . . . Old and tired . . Us and the bikes . . . . . . Quote Link to comment
Jonboy Posted January 8, 2016 Share Posted January 8, 2016 17 hours ago, Havoc said: I wouldn't put it past it, sneaky german wobbly wheeled emissions cheat. I'm trying to imagine what would make this kind of sewing machine noise, cam chain running over metal (if the rubber's really worn on the tensioner blade? It did do 60 ish miles with a slightly over tensioned cam chain. I'll whip the rocker off tonight see if anything jumps out and smacks me in the face........ tis sounding more like cam chain related, didnt realise you had a 60 miler with a tight chain, good place to start......... Quote Link to comment
Havoc Posted January 8, 2016 Author Share Posted January 8, 2016 Had the rocker off last night but didn't have enough time to really get into it. On first inspection cam chain/cams etc look to be fine, but I need to measure between the inlet and exhaust cams to see if they're out of tolerance now. And pop the cam caps to see if there's any damage to the bearing surfaces. It almost sounds like the starter clutch isn't disengaging although after stopping the motor it starts again fine on the button. I think if the motor had been spinning the starter for what is now 200 miles the thing would have given up pretty quickly. I'll drop the oil and look behind the covers this evening. Thanks for your input folks Quote Link to comment
Havoc Posted January 8, 2016 Author Share Posted January 8, 2016 2 minutes ago, Havoc said: Had the rocker off last night but didn't have enough time to really get into it. On first inspection cam chain/cams etc look to be fine, but I need to measure between the inlet and exhaust cams to see if they're out of tolerance now. And pop the cam caps to see if there's any damage to the bearing surfaces. It almost sounds like the starter clutch isn't disengaging although after stopping the motor it starts again fine on the button. I think if the motor had been spinning the starter for what is now 200 miles the thing would have given up pretty quickly. I'll drop the oil and look behind the covers this evening. Thanks for your input folks I also backed the tensioner off a 1/4 turn before the last 140 miles and to be honest I don't think it was too bad to start with, adjusting the tensioner was just the last thing I'd done. I did it the same way I always do, finger tighten until you feel a little resistance then back it of 1/4 turn. Again now the rockers off I can assess whether I had over tightened it. Quote Link to comment
Havoc Posted January 8, 2016 Author Share Posted January 8, 2016 Think I've found it but it's a wierd one. Dropped sump to check for nasties, clean as a whistle All good up top, cam chain hadn't been over tightened All good down bottom behind the generator cover. Only damage I could find was on the tacho drive screw, would explain the whirr, can't find why it might have happened Who'd have thunk it... Quote Link to comment
kitkatman Posted January 9, 2016 Share Posted January 9, 2016 Had a whine on my ET when I bought it 12 yrs ago. Only got it in 4th and 5th gear, hard surface on the 2 gears was breaking up.So new gears(lots of dosh) problem solved. Quote Link to comment
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.