vance and hines query
Posted: Fri May 08, 2009 7:20 pm
Any of you chaps know if any jetting changes are needed when fitting a Vance and Hines 4-1 onto an otherwise standard 1000A1?
Cheers in anticipation
Cheers in anticipation
I haven't jetted mine yet, however......When I first got the bike the previous owner had removed the stock snorkel/silencer under the seat which connects to the box that houses the air filter. A month or so after getting the bike I put the V&H on and all was good. Over the winter of '07-08 I re-did the ignition system, dyna coils and electronic ignition as well as the relay mod as the coils weren't getting 12V (they were somewhere around 8.6).
When riding season began I was still running the bike w/o the snorkel and a major flat spot showed up right around 5000 RPM and it just wouldn't pull much beyond that. Plug check revealed lean condition on all four. Just to try a theory I put the snorkel back in and the flat spot disappeared and it pulled strong again all the way to red line. Plug checks afterwards revealed a fairly tan colour but on the still a bit on the lean side imo. My guess is that with the weak ignition this lean problem didn't show up. By putting the snorkel back in I've restricted the air intake and balanced it back out again.
TBO, I think one size up on the jets would do the trick just fine, but as (knock on wood) it is working just fine as is, I'm going to leave it until I have to pull the carbs again.
Hope this helps.
