@ 1st and 2nd i have good acceleration buy recing it hard but in 3rd,4th,5gh,6th no good in accelaration it remain on 60kph but it is reving high i run with out air box and when i put air box it doesn't rev high and it die..
It won't run properly without the airbox If it won't idle with the airbox in place you need to deal with that situation
Is the EXUP working properly ? Have you tried running it with the airbox and using the choke? If so does it rev any better or worse ? Have you checked the fuel filter, and the 2x filter's on the pick up inside the fuel tank, there is also another fuel filter where the hose from the pump goes into the plastic t-piece on the fuel rail on the carby's are not blocked up, and also how much fuel the fuel pump put's out ? Fuel tap could have a blockage ? Have you checked the fuel level's in the carby's ? How many rev's is 'high' when it's doing 60 km/h ? My FZR250 3LN3 can do close to 80 km/h in 1st gear @ 18,000rpm, and about 110 km/h in 2nd gear at same rpm They are quite hard to tune without an airbox, it will respond well in some of the rev range, but it's very hard to get the mixture's right in other rev range's I have only seen 1 FZR250 that's ran and revved well through all rpm with foam pod filter's, but it was in a video (which i have tried searching for and am struggling to find again), so i don't know if it performed as well under load with someone riding it
First thing, do you know what model of FZR you have? Look here: http://2fiftycc.com/index.php?threa...0-3ln-bodywork-frame-engine-carburetors.3469/ The carbs on the FZR250 only work properly with the airbox and air filter installed. Running without both of them means the engine is running really lean, and the air is unfilitered. This will lead to engine damage. Put the airbox back on (make sure the rubber boots seal properly and are done up tight) and adjust the main idle on the carbs. If the bike bogs down at low revs and uses a lot of fuel, the needles and tubes are likely worn out.
We can't really. I wouldn't attempt it unless you're prepared to make things very difficult for yourself.