Been asked a number of times on this issue, so here's the scoop of what and where and all that jazz.
on bike for 6yrs
I gathered tons of info over the yrs on this, from reading as many as 300 or so posts on VOES
, discussions with a tech at Dyna
(who so happens to ride a Roadie)
I've run the 42 with no mod, Voes mod, and finally TPS
Stock ignition module and 42 carb will give the error flashes without a TPS
Dyna3k and 42 carb no flashes without TPS
By default with either module and no TPS by default unit goes into WOT
timing, it is ridable.
After much reading on VOES, decided to try it, recommended VOES was a 3hg for stock pistons 5Hg for HC
pistons. The idea is to force CT (close throttle)timeing and when vacuum decreases goes into WOT timing. Voes works as an on/off switch, and that it. With the voes closed it provides 0 volts, open there is 5 volts to module.
Purpose of the TPS is to send a voltage signal to the ignition module. Usually at idle the voltage is approx .8v at approx 4 volts it goes into WOT timing. Once at that voltage, WOT timing does not change, so no matter what you do twisting the throttle, 5v, timing is still the same.
The big difference is in CT timing, info I gathered was at every .2 volts there is a timing change, so on avg there is approx 15 timing changes taking place in CT timing before it gets to the voltage threshold to swing into WOT timing. The voes does not allow for this, it's either 0 volts or 5 volts.
It will not add HP
it will not add TQ, so lets get that out of the way.
What I noticed with my bike, from VOES to TPS
Immediately I notice a exhaust tone change (for the better)
Leaned my pilot
jet by half size (25 to 22.5)
Better off the line acceleration (smoother)
Consistently 2 to 3mpg increase in city riding.
I know a few have said it is not needed, but yet they have not done it on a Roadie, have heard they tried it on a different bike and felt no difference. Sorry, but I won't compare an apple and an orange. Other than that, only heard 1 other person say they did not see a difference.
Take what ya need...toss the rest