i bought a cbr 125r and it seems to have quite a bit of power and i'm only a lerner (cbt) so if this bike is not restricted i won't be able to ride it legally, so can you please let me know how i'd tell if it's restricted, many thanks

tony, December 2006

you dont need to rejet it , i have an aftermarket micron with baffles removed , theres not that much restriction on the standard system anyway , the bikes not really restricted in any way , just a small 125 4 stroke thats all

darren, August 2008

last answer was total rubbish,paul there is no restrictor in the front of the pipe the baffles slow the bike down a little bit so an aftermarket pipe would make it breathe a bit better but you would also need to change the jetting in the carb to compensate for the extra air flow,also there is no reeds on a 4 stroke engine PAUL only a TWO stroke engine has reed petals or a rotary valve,the sprockets could be changed but they will not necessarily give you anymore speed in fact its likely to lose top end if you gear it too high these machines do not pull well in top gear from standard

adam the bike dcotor, December 2006

the exhaust at the engine will prob have a reducing pipe iside it, if you undoo the exhaust you should be able to see it, also the drive sprocket and rear wheel sprocket are changed along with the reeds in the carb, its not really worth messing about with, but the exhaust one gives the best improvement

paul, December 2006