Hi there! at the moment i have a TNT air filter and i want to put it on my original Dell'Orto PHVA 12DD carb. i take it the carb will need to be upjetted? is it the main jet i change? my haynes manual says the main jet is 66. i was thinking 0.80mm jet? Help please?
It should need that much I believe, I've read somewhere it needs a 10% jet increase(not sure thou) if your engine hasnt got any other mods give it a try without upjetting it, let it warm up, up and down the street at WOT stop, let it cool down and check the plug colour. Bit if you have an aftermarket exhaust you better upjet, it will seize otherwise. never good... Good luck
Or just don't do it. Complete useless mod on an otherwise standard bike. It will generally increase the noise, reduce the performance and use up more fuel. So pretty much don't do it as it is a no gains mod that if you get the jetting wrong will seize your bike up pretty quickly.
