hi everyone,

trying to figure out strange vibrations developed over handlebars and foot pegs.

So long story short, bought the bike when it was 16k miles on it, bike was smooth and was running perfect! around 19k mark I have decided to do valve clearance, carb synch and plugs. Bike was still running perfect! nice and smooth engine and preformance!

now my baby have around 23-24k miles on the clock. Since few weeks I have noticed very anoying vibrations (most of them around 3.5k rpm - 6k rpm range). here is the list of stuff that I have checked out so far:

- first thing was the bolts holding engine (everything tight)
- again valve cover went up and clearance is in norm
- cct seems to be ok (possibly my next step to change it for manual APE one)

now I suspecting only one more thing, drive chain! I actually adjusted it maybe 3 times since I get the bike, I always lube it a lot! is it possible to get vibrations nearly over all bike when drive chain have tight spots or is stretched too much? I still have around 3 bars left on the swing arm adjustment...

so the main question is: should I drop the rear wheel and quickly check drive chain for tight spots? or maybe it is related to the carrier bearing on the front sprocket?

anyways the vibrations knocking my confidence, and make me feel bad

anyone here have more ideas? thanks in advance for any helpfull informations!

 

Yes. A badly worn chain can't properly be adjusted due to those tight/loose spots. You'll feel that in the ride. Get yourself a new chain & sprockets, & you'll get that nice smooth ride back (or you should).

 

cool, before chain I actually have to inspect one more thing... ignition coils and air filter. noticed in the mournings when engine is cold bike runs quite rough for a couple of seconds (working like on 3 cylinders only). then it kicks in, I just came up with that idea now! sure uneven ignition might make engine to run unevenly... then the pistons trying to level it out and thats when vibration might come from...

will post some more details after I inspect everything tomorrow.

 

ok, inspected everything what was possible.

- chain seems to be still ok (no tight spots,sprockets still look like they're ready for another 5k miles)
- airfilter was a bit dirty (gave it a proper clean also waiting for brand new filter)
- ignition coils (no sign of damage,no kinks,all connectors seems to be ok) sparkplugs where changed at last valve check

the only thing that might couse my problem is CCT... is not completly damaged, but as the engine warms up I can hear a bit of tapping noise, also can hear a bit of swoosh from cam chain it self.

 

also another Q, can I "experiment" on the actual tensioner? what I want to try is start turning it clockwise paying attencion how many clicks I have, and then go anticlockwise and add one extra click (if there is any)... what y's think?

 

before you a new chain and sprocket repeat the test in neutral with the bike standing still. still vibrating ? it's not the chain,nor any other ground related part like the wheel bearing etc.
stopped vibrating ? well, the engine is fine so is the clutch. still maybe the gear, wheels, chain etc.

 

ye engine still vibrating on nutreal around 4 - 6k rpm, will check cct tomorrow, actually engine started to develop click-clack noise over last 3 days (so far only when is cold) as I said valves are in norm, I'll see if I can put my hands and inspect clutch especially friction plates this week.

 

one other thought. I suppose you already took the fairings off.
put on each exhaust header a drop of water or oil, start the engine cold, and see if one of the header smokes less than the rest. this would indicate a cylinder not running properly.
causes for this is either ignition or fuel.

good luck!

 

Is it only at a certain rev amount/range or is it at a certain speed? Does it increase and decrease when speed does?

 

certain rev actually, puting APE manual cct tommorow or saturday... (depands on post) will provide info after I change it...