ok i hope im not being stupid but ive just read the airbox guide and it seems obvious that they are better than race air filters. so my question is why does any1 use air filters? and if u up-jet with an airbox will it make any difference? just wondering cheers imp:
you can drill holes on ur standard air box and upjet lol if u upjet with out driling wholes in it will be running too rich
dont just drill random holes in the side. xan mod the airbox. but need to make the inlet of the box the same size as the carb venturi and remove any restrctions inside the box and just make it as smoth as possible for the air to flow with.
When I bought a Malossi (OK Dellorto) carb for my Aerox, it came with modification instructions for most airboxes with diagrams. I should think that most people buy those K&N filters because they look good. Like those "race" fans which do nothing at all. Dealers will say anything to get your money.
its about understanding how an airbox works, and improving it it starts at the intake pipe and ends at the carb... The reason people fit open filters is simple, open filters allow more air into the engine, which allows a 70cc to breathe better!!! its the open filters that are flawed, not the concept
yeh your probably right px, i just wondered as so many people seem to be getting race air filters. will these race air filters with jetting actually be any faster than a standard air box? cheers
true , only have mine because i got it for free and it looks cool , also it makes a sweet sort of induction noise , but performance wise its uselsess
If the reason they have to up jet after fittin an open air filter or race air filter is to compencate for fuel lost, surely its better to keep the standard air box and keep the fuel u wud be wasting and that will do the same performance as a race filter and jetting? i dnt get it ha ha its all so confusing
An open filter allows the engine to suck in more air than a std airbox, The carburettor is calibrated to the airbox, change the airbox for an open filter and the carburettor is now out of calibration now a bigger main jet is needed to calibrate the carburettor to the open filter, and possibly the mixture screw adjusted...or a bigger pilot jet none of this means extra power though on its own, its a matter of calibration
If you need to upjet when you replace the airbox then its quite clear that the restriction in the intake is the airbox this will cause less presure drop across the jet so they flow less So there for you have to increase the jet size to compensate If you find that the this is the case then there will be a performance gain as the engine was capable of using more air than it was getting other wise you would not of had to upjet
i have a e5airfilter i upjetted and fiddled with the carb it is much faster with the open airfilteron my bike
