checkley8 Posted August 11, 2009 Share Posted August 11, 2009 Hi, ive just brought a new leo vince tt exhaust for my Yamaha Aerox YQ 50 and have removed the restrictor cone, however i have lost all of my acceleration and have heard that you need to do something with the jests to let more fuel through any ideas??? Cheers Link to comment Share on other sites More sharing options...
wild foamy Posted August 12, 2009 Share Posted August 12, 2009 hi there idealy you will need to change the main jet to a larger size to compensate for the higher airflow through the engine because of the new exhaust, you may also want to change your rollers to a lighter set and stiffer clutch springs for faster acceleration take the bike out for a spin and full-throttle it, then cut the engine and coast to a stop,remove the spark plug and check the colour of it on the end (should be a dark brown/chocolate colour or black), if it is white and chalky this indicates a lean running engine which will soon destroy itself Link to comment Share on other sites More sharing options...
checkley8 Posted August 12, 2009 Author Share Posted August 12, 2009 hi there idealy you will need to change the main jet to a larger size to compensate for the higher airflow through the engine because of the new exhaust, you may also want to change your rollers to a lighter set and stiffer clutch springs for faster acceleration take the bike out for a spin and full-throttle it, then cut the engine and coast to a stop,remove the spark plug and check the colour of it on the end (should be a dark brown/chocolate colour or black), if it is white and chalky this indicates a lean running engine which will soon destroy itself ok cheers, do you know what size the original main jet is and what size i will need to increase to?? Link to comment Share on other sites More sharing options...
leigh dt 125 Posted August 12, 2009 Share Posted August 12, 2009 ok cheers, do you know what size the original main jet is and what size i will need to increase to?? only way you'll find out is if you take the jet out, on my old moped i got a new exhaust for it and had to put a size 86 jet in but might be different for yours, if u can take the jet out and go to a motorbike shop and ask them what jet you would need and explain to them what the bike has got done to it then they should tell you the correct size thats wat i did with my old moped Link to comment Share on other sites More sharing options...
barwell1992 Posted August 12, 2009 Share Posted August 12, 2009 have you changed the rolers if not then there is no point in even starting to mess with the carbs untill you change them and you will need an impact wrench to do so Link to comment Share on other sites More sharing options...
checkley8 Posted August 13, 2009 Author Share Posted August 13, 2009 only way you'll find out is if you take the jet out, on my old moped i got a new exhaust for it and had to put a size 86 jet in but might be different for yours, if u can take the jet out and go to a motorbike shop and ask them what jet you would need and explain to them what the bike has got done to it then they should tell you the correct size thats wat i did with my old moped Have took the jet out and took it to my local motorbike shop and asked them but they told me they do not know and to experiment with different sizes, cheers anyway Link to comment Share on other sites More sharing options...
ReIcE Posted August 19, 2009 Share Posted August 19, 2009 When i replaced my standard exhaust with a sports pipe i up-jetted 10 sizes which didnt show no change. The most common modification you have to do when you change the exhaust is to change the rollers to a lighter size. I changed my rollers down to 4 grams. my bike ran sweet with very good acceleration. Link to comment Share on other sites More sharing options...
Ski-Dennis Posted August 19, 2009 Share Posted August 19, 2009 When i derestricted my aprillia sr 50 ? didnt touch the rollers or didnt change the carb, just thought what the hell wanna go out on it and race every one 2 weeks later it broke and had to sell it for spares and repairs loved that bike Link to comment Share on other sites More sharing options...
Recommended Posts