2007 v-star 1100 spark knock? (detonation)?

Question

well, i've got about 480 miles on my 2007 v-star 1100 now. i've added a set of full pipes, and nothing else. i just bought a half helmet to wear, and took the bike for a ride yesterday to get a feel for the helmet over my full face helmet. i noticed a noise, similar to a spark knock. i never noticed this before (maybe because of the full helmet muffled the noise?) or did this just start? i have not jetted the carbs because the bike seems to run good, and the spark plugs look great. could this possibly be a spark knock? or is this a typical sound from the yamaha's? anybody else have a similar question or complaint from their yamaha? thank you.

Answer 1

Depending on what type of pipe you put on, you could have to rejet if it's not fuel injected.

Answer 2

You almost always need to re-jet when adding different pipes.  You may be running too lean and this can cause spark knock

The spark knock must be fixed.  Detonation can cause burned valves and pistons.  You better get it sorted out soon before you do some serious internal damage to your engine.

I personally wear a full face helmet on my cruiser.  I had a friend take out a speed limit sign on a 4X4 post by hitting it face first.  The only injury he had was he broke both knee caps when he went over the handlebars.  He was wearing a full face helmet.  A half helmet wouldn't do much good in a wreck like this.

You never know how your next crash could happen.  It is better to be wearing the correct helmet and not need it than to need the correct helmet and not have it.

Answer 3

What grade fuel are you using? Run a tank of the high octane and see if the noise stops. If it does not stop, it might be possible that you have an exhaust leak from the installation of the pipes.