Bus Driver 0 Posted January 31, 2011 Hi guys & gals, this question has proberly been asked a thousand times but here goes, if I fit a K&N air filter to a 2003 1200s Bandit do I need to make any alteration to the fuel side or is it a case of suck it and see? I have read somewhere that they tend to run lean as there is more air getting forced in. Any help would be apprechiated, oh and one more thing does it make the bike go any better in terms of performance Thanks again, Andy..... Share this post Link to post Share on other sites
Bezzer 0 Posted January 31, 2011 If you've fitted an aftermarket can as well then you're going to need it rejetting as you will be running lean. If it's a K&N panel filter then it'll want a stage1/2, if K&N pods it's stage 3. Get a Stage3 kit and it's has the smaller stuff in it for a stage 1 then you can also use it for stage3 as and when you need to. Filter, can and jetting should see a nice increase in power. Share this post Link to post Share on other sites
darkember 0 Posted April 25, 2011 I have a further query to this thread. Agreed K&N pods will need at least stage 2 or 3 depending on your can. However, leaving the K&N out of the equation. If you fit a can then u may get away with doing nothing. Ok now you decide to stubby that fitted can would I be correct in thinking that one may now need to fit at least a stage 1 kit???? Share this post Link to post Share on other sites
Bus Driver 0 Posted April 25, 2011 The K & N filter I fitted did not need any adjustment whatsoever to the fuel.I checked the plugs and they told me the mixture was fine.But I have to say that as I only had it in for 3 weeks. Share this post Link to post Share on other sites
trebor4460 0 Posted April 26, 2011 Fitting a k&n panel filter and their is a very gud chance u will have flat spots in the rev range due to a weakened mixture, specially if u fit a free flowing zorst. You are gonna need to fit a stage 1 jet kit.Fit pods or cones and you are going to have to fit a stage 3 kit and get some rolling road time in to get her running right, pain in the arse and can get expensive but once jetted right you can see as much as 30% increase in Bhp on the 1200.If you stubie your zorst you might very well see a drop off in torque mid range due to the changes in back pressure, also mid range carburation tweak might be required, they do look and sound gud though. Share this post Link to post Share on other sites
Skelly 0 Posted April 26, 2011 I changed the can but kept the standard filter and had no problems with the standard jetting. Then a few months later fitted a K N filter and found that the engine wasn't as smooth especially at lower speeds, have now gone back to a standard filter and all is well again Share this post Link to post Share on other sites
