OK, so for the last couple of commutes, I noticed that when I go over a big bump there's a kind of rattly/tap sound. To me it sounded like a loose bolt in the headlight unit or maybe under the airbox cover.

Poked about - can't find anything.

So tonight I get to my bike and start it up to head home. It's on it's side-stand and I'm standing next to it.

As it coughed a bit when it started up I gave a little throttle and heard this God-awful rattle...



It seemed to be coming from the area I indicate, but could be lower... was hard to pinpoint really.

What the hell is it???

Weird thing is, as soon as I put the bike upright (ie, off the sidestand) or sit on it, the rattle goes away.

Could it be my new isolator? Do they do rattle like that?

What the hell else could it be??

Am starting to remember why half of Buell ownership is a 'hate' relationship.

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"Because it's awesome" is always a good enough excuse

http://www.eugenereisch.com

You sure it isn't the horn bracket broken ...i seem to remember lots of folk having their horns rattling behind the flyscreens on Xb's ............... and sound does tend to travel sometimes

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2001 X1 2009 1125CR 2006 Uly X3 2010 Uly a fully Maz'd S1 and a 1991 RS1200 Westwind.

I'll check it tomorrow but I don't think so.

It's weird that it goes once sitting on the bike or taking it off it's side-stand

and also hear it when I go over a bump, thus unloading weight on the bike??

_________________
"Because it's awesome" is always a good enough excuse

http://www.eugenereisch.com

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If your dreams don't scare you, they are not big enough.

G Bennett, Esq

Sounds like the rattle only happens as the revs pass through ~1500rpm...?
If an Uly is like an M2, that part of the rev range is when you feel the most engine vibration. Could your new isolator somehow be allowing part of the engine or bits attached to the engine to hit the frame or airbox cover etc?

Or I've read on here that early Ulys (not sure what year yours is) can have problems with the throttle butterfly shaft breaking or coming loose... No idea if that would cause that sort of sound tho?

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2001 M2
2001 XLH 883
2016 MT-03 660cc single

Sorry chaps, what am I missing?

Or was that just a general, "shit, that sounds bad" comment?

Eek.

_________________
"Because it's awesome" is always a good enough excuse

http://www.eugenereisch.com

Doesnt sound too much like engine noise just something rattling outside the engine. The above sounds plausible or are you sure that something isnt rattling around under the tank cover?

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Buell S1
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Buell XB12S
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BSA B441VS
FJR1300

it does sound metallic - though if you think its coming from that area may be worth checking in the airbox or take it off and have a good look see.

It actually sounds 'hard' if that makes sense and seems to correspond directly with how much the engine is vibrating, so perhaps something is loose and knocking against the frame?

I'll pull the airbox assembly apart later and check that out.

_________________
"Because it's awesome" is always a good enough excuse

http://www.eugenereisch.com

Solved!

The front osolator bolt was a bit loose - just needed torquing up a bit.

Rattle gone. Me happy. Loving Buells again... until next time

_________________
"Because it's awesome" is always a good enough excuse

http://www.eugenereisch.com

Good to hear it,in mine the bolts holding on the ignition coil snapped and I found it to be bouncing on the bracket! Happy days for you