when my bike is nice and warm from riding a while i notice that the motor rattles a bit at certain rmp ranges. i'd tell which ones but nightsters, as most of you know, dont have tachs.

i did a search on this forum and everyone seems to beleive thats its just a noisy bike and that the rattling is normal....

it sounds to me like detonation...where the spark occurs before the fuel is injected. i had the problem on my mustang when i had an open exhaust with no tune...

could this be the problem in my nightser? or is it really just the lifters or something making a totally normal noise for the evolution motor?

 

Thanks for posting, same thing happening on my Nightster yesterday during a 100+ mile ride and it drove me nuts. I too have searched and apparently unless something blows up its normal.

To expand your question, which might help a lot of us out, has anyone actually had this noise BE AN ACTUAL PROBLEM that needed to be addressed? It's hard to tell on mine if its actually detonation or just valvetrain noise. About to take mine to the dealer as its still under warranty...

Sorry I'm no help but your description of the noise is great, hard to explain such things online

 

I thought I had just such a noise and it turned out to be the gas cap rattling.
On the other hand, have you tried running higher octane fuel? That is the advice for detonation as a rule.

 

91 octane is as high as we get here in CO and thats all I put in the bike

 

I use 93 I don't think its the gas cap because its only noisy when warm.

 

I get that noise on my 2008 EFI - I`m pretty sure it`s detonation as well - maybe running a bit lean.

 

AKA-pinging

 

A stock EFI bike should not have detonation, absolutely no reason for it.

 

Why not try a fuel additive to detirmine if that can remove the noise!

 

Have you checked your primary chain adjustment?