question on jetting

[K-Dog]

Thinking of using a cobra exhaust will I have to rejet the carbs you do on other scooters???

[mmurffy03]

don't have to but most Valkyries seem to start and don't need as much choke to warm up after going up 1 size in slow jets from #35 to a #38 jet others might agree I have a set of cobras with no fast/main jet changes  seems to run fine they very loud even with baffles and ran better with stock exhaust on it just my opinion

[9Ball]

I had my bike dyno tuned at the dealer and gained back 7 hp by rejetting the mains to 105s and needle clips on the third notch.

Do you have to, not really but you may want to.

[salty1]

I have Cobras on my 97 Std and it runs just fine with stock jets and a K&N air filter. You may need to turn your pilots up about a 1/2 a turn depending on if you have any decel pop.

[mirion]

Running stock jets on my 97 with Cobras and all is fine, its starts great with no choke except really cold days unlike my 2000 IS with glass packs. The IS always needs the choke and some warm-up time. I am pretty certain that the IS would take the 97 in the 1/4 though but these bikes have horsepower to spare so I elected not to mess with the carbs.