Triumphrat

kiwiraca · 03-20-2008

i`ve put pipes and jet kit on my bonneville i guess next step is airbox ,lots of information here but no one says how much difference to power ,noise ,mpg it makes to an otherwise stock motor.

Sheepdog · 03-20-2008

I have a stock 790 motor with BellaCorse Teardrop mufflers, N-H Bellmouth (snorkle removed), Uni Filter, #125 mains, #42 pilots, Thruxton needles (no shims), and idle mixture about 2.5 turns out. I got modest power gains with much better throttle response and better starting. Popping on decelleration is eliminated (AI removed). I suspect that I am a tad rich, but the bike runs very cool and I have decent color on the plugs with no carbon build-up. This combination produced some noticeable gains, but certainly no more than 4-5 ponies. My approach was aimed at improving refinement more than peak horsepower...

Oh, and it is a bit loud. The Teardrops allow more sound than TORs, but not as harsh as D&Ds or Bubs.

chedd · 03-20-2008

Mine is a 790.
K&N filter, bafflectomy, thrux needles, one shim, snorkel removed, 115 mains.
I'm currently running the standard 40 pilot jets but as I'm 3 1/4 turns out on the pilot screws I've ordered some 42s.
I enlarged the intake area of my air box and found that it really made a noticeable difference.
I'm yet to replace my pipes. The increase in power is not huge but noticeable and response feels better.

RedBird · 03-23-2008

Mine dynoed at 67.5 RWHP a little over 18000 miles ago. I can't tell that it has lost much in those miles. My mpg is the same as it was stock (after a couple thousand miles of break-in)...50+ mpg. IMHO, the 790 really responds to airbox removal and less restrictive silencers. I do recommend getting the carbs set up on a dyno.