What the heck is causing that noise?!

[kenny b]

When I hit bumps or dips, even small ones, I hear kind of knock. I tried to replicate by holding front brake and pump the front end, but does not happen. It seems to be front end somewhere. Thought it might be fuel tank float bumping tank, but doubt it. I know potentially it could be many possibilities. Any suggestions I can look in to?

Thanks,
Mike 86 in San Dimas

I have a 92 fj i doubt the mirrors are the same but i had the clunking problem after tinkering around with the bike during the winter.I noticrd there was something loose inside both of the mirrors i definitely believe this is where the noise is coming from. May noy not help the 86 fj but if anyone has a newer 1 positively check your mirrors the original stock mirrors that is

[andyoutandabout]

The standard Fj mirrors on an 86 certainly have big chunks of metal in them, that clunk around. I had to drill the plastic surrounds and drop them out - they were enormous.

[junkyardroad]

My oversprung inverted fork made a knock on small bumps.  I finally figured out that the too weak rebound dampening combined with too stiff springs was causing the fork to top out. I could not make it happen in the garage.  What weight fork oil do you have?

[Klavdy]

The standard Fj mirrors on an 86 certainly have big chunks of metal in them, that clunk around. I had to drill the plastic surrounds and drop them out - they were enormous.

Fuck me dead Andy,drilling them?
You've been with the Seppos too long.
Next time use a credit card and a hair dryer, soften the plastic with the hair dryer and pop the mirror out by sliding the credit card underneath it.

[andyoutandabout]

Now that's a clever idea. However I've standard mirrors no more. Cheap EMGO replacements now grace the 86. They lend a most modern look. Spiffing.

[ren-dog]

When I hit bumps or dips, even small ones, I hear kind of knock. I tried to replicate by holding front brake and pump the front end, but does not happen. It seems to be front end somewhere. Thought it might be fuel tank float bumping tank, but doubt it. I know potentially it could be many possibilities. Any suggestions I can look in to?

Hey Mike,
Is it a clunk, bang, clatter or 
If you have a little too much run out, or warp, in your front discs
it could simply be the disc pads rattling around.
Does it still make the noise if you hold your front brakes on lightly?

[elbows]

Mike,

my 86 does make a  clunk when I take it off the centerstand and sometimes when riding over bumps. I traced it to the spacers in the forks moving around. do you have aftermarket springs in your fj?

mark you are right this is the second set of forks i have rebuilt and the shims to and bottom worn out and when rebuilt the noise has gone and the forks feel fantastic like new again but remember to change the plastic washer as well