Rattle at Startup....What's Wrong?
 

When I fire up the bike, hot or cold, I get a sharp rattling sound on the left side when it fires up...it sounds like it's coming from the primary, but I can't tell for sure. It fires up first try, and runs fine when I'm riding around, but this rattling sound is disconcerting...this began yesterday. About 700 miles on the bike so far. Any ideas what it'd be?

I'd get it back to the dealer ASAP for warranty service.

Check that everything on that side is tight (peg, shifter, linkage etc.). Something could just be loose and rattling. If not take it to the dealer.

Well, that wasn't quite what I'd expected. The stealer is only about a 10 minute ride for me, so I shot on down to the service center, and had one of the mechanics take a look at it.

I told him it had just crossed 650 miles on the way over, and that I was getting a nasty sounding rattle from what sounded like was in the primary. He fired it up 4 or 5 times (and of course it didn't really do it that badly any of those times :mad:) and said it was still breaking in and that I'd be getting "all kindsa weird noises during that period". I said I figured that period was pretty much past about 150 miles back and that it hadn't done this until yesterday. He said to keep an eye on it, and that was about it.

So I guess I'm gonna keep an eye on it for a bit.:mad: Like I said in my first post, it runs perfectly on the road, just this weird rattle at startup. I'm kinda irritated.

Not sayin this is your problem, but mine did that sometimes when I fired it. I finally found that the spring washer on the left side foot peg wasn't enough resistance so it rattled a little, so I added another washer & it tightened it up & no more rattle! Hopefully it's somethin like that, just check all that simple crap! Good luck man.

By the way 650 miles :eek: Get out and ride lol JK with ya. :D

Check your horn - That stupid thing loosens up on me every few hundred miles. With a new bike loctite is your best friend.

Like it was previously mentioned, check for loose hardware. Check your jiffystand and make sure it is hitting the rubber bumper on the frame under the primary, if not, adjust the bumper. A major problem would be the primary chain adjuster not taking up the slack in the chain and the chain is slapping things around in the case, not a good thing. When the chains get hot they tend to get tighter and the slack tends to go away.

Just went out and did my own check...oil level is perfect, nothing is loose anywhere around the chaincase, pegs, etc.

My next step will be removing the derby cover (and entire primary if necessary) and seeing what's going on...I should be able to tell right away if the tightener isn't taking up enough slack, right? I don't think that's the problem.....at least I hope not.

Thanks for the suggestions so far guys.

I've got 260 kms on my fatbob and my left rear fender strut is rattling. I'll probably fix it myself when I install the detachable backrest and easy brackets.