| Author | Message | ||
     Cabrainerd |
So I've tried adjusting my primary a couple different ways (noise method and via inspection cover), several different times and its making me feel like something is wrong internally. I have an 06' 12X w/ 29k mikes, 4k of which are mine. It all started after I dropped the oil pump to check the teeth on the drive gear (thankfully a clean bill of health). when I finished up I decided to adjust the primary chain and found a really tight spot with the loosest spot at around 1/2 inch. I decided to loosen it up a little and relieve some stress. When I fired it up I got a quick rattle (like on the inside of the case) followed by normal operation. Ever since then I cant get the rattle at start-up to go away completely. I've tightened the chain till it makes no audible noise, then to when it sounds normal when idling, but has a slight whirring noise on engine decel when you blip the throttle. It does seem to go away or be less audible when the chain is tighter, but a whirring sound makes me think to tight even if I only hear it when the engine is decelerating. Anyone have any suggestions? When checking slack along areas on the chain I would put it in 5th and push is to rotate the engine, and a few times I pulled back to rotate backwards; could I have backed the nut off the crankshaft? Keep in mind shifting and noise other then start-up is normal, its only rattling like the chain is hitting the inside of the case for a quick second at start-up... | ||
| Argentcorvid |
Broken tensioner? Pain in the butt to check, but it sounds like you'll be going in there for one reason or another anyway. | ||
| Fast1075 |
"Could" be a loose crank nut causing the noise. | ||
| Reepicheep |
That makes no sense... If it was a loose crank nut (which you would never be able to cause by moving a rear wheel no matter how you moved it) it would be a light "gonging" sound, and it would go away if you lightly load the clutch (enough for idle to drop but not enough to move bike). I'm pretty sure it's not that. The rattle and whir can be caused by chain tension, but it shouldn't change after a short warm up. Here is a thought (but not a good one)... what if it is the 5th gear drive assembly? Try taking a cold bike, and lean it as far over to the right side as you can (pre-oiling that 5th gear drive assembly), then start the bike. If that keeps the problem from occurring, that isn't good. You could then further check by removing the belt and putting it in neutral and turning the output pully by hand. It should be smooth, not crunchy. Otherwise, pulling off the primary isn't that bad, and if you are careful you might even be able to reuse the gasket fine. That lets you check the primary tensioner. I'd start with a milk crate and a clear head, and redo the primary chain adjustment from first principals from the manual, ignoring everything you "think you know". Measure in a lot of places. Then see if the problem persists. It would be unusual to break one of the new tensioner shoes, but it could be done if somebody just went nuts with the adjustment. | ||
| Cabrainerd |
Thats what I was thinking... Its not exactly that it changes after a short warm up, more of its a quick knock on startup and then it operated normally. Its over by the time my finger get off the starter button.. Today I went to start it up 3 different times throughout my day and it didn't make the sound. It is tight enough that I hear a slight whirr on deceleration, but I have to have my head by the primary while reving on the stand to catch it. at idle there's no audible whiring sound. I don't think its a trans problem Reep, but if I have to pull the cover off and its not the primary I'll have to dig into it. 5th is smooth in testing and riding. I'm thinking a really slack spot in the chain? Would explain why it does it sometimes because it stops on a tight portion or a slack portion on the rotation and the next time I would fire it up the slack would slap.. Anyone hear of anyone getting that much variation in different locations on a primary chain? If I tighten it any more I get a smidge less then 1/2 play in some areas and a guitar string at others. Probably wont know till I to pop the cover off.. Thanks for the replies guys. | ||
| Natexlh1000 |
Remember that the chain tightens as the case warms up. Aluminum expands more than steel. A little loose is better than too tight. | ||
| Reepicheep |
Yup, adjust warm for appropriate slack at tightest spot, and don't worry about the slackest spot. Unless it is stupidly slack, the worst case is it will just grove unimportant inside parts of the primary cover. |
