Must I jet
#2
Well, buy some new spark plugs,do the mods you listed, install the new plugs. Now take it out and run it W-O-T then shut it down and do a plug check. That should tell you what you want to know. You might want to go to your dealer first and buy some bigger jets and have them on hand. the v-force is very easy to rejet. I think stock jets on the v are 135 f and 138 r. The plugs should look tan to light brown, hope that helps.
#4
Whenever you modify an engine to take in more air/fuel you will make more power. I don't know how much of a power increase you will get, but the jets are abuot 5 bucks apiece and you don't have to take the carbs off to re-jet. Just look at the bottom of the carbs take the 4 screws out of the bottom of each carb now take the bottom of the carb off, the main jets are now visible. ( note: there is one hex key screw in the very bottom of each carb, this is to drain the carbs so you don't get a face full of gas when you take the bottom off.) Takes about 10 or 15 minutes. You should change your primary sping to the EPI pink or its equivalent, that is one of the bests and cheapest mods you can do to a stock V-force. EPI pink spring 19.95 + shipping.
#6
The primary spring is a component in the cvt clutch of the V-force. It controls RPM stall and shift out rate. The stock spring really doesn't do a very good job over 40 MPH. The EPI pink spring has about the same stall as stock, but dose a much better in the mid and top in.


