Hello users, I've got an RS125 and what a bad decision i made to get one... I've rebuilt the engine, new crank, con rod, crank case and new 1st gear cog... and ive rebuilt the bike and everything i thought was fine... until i started it up. My bike isnt mixing its fuel properly, it cuts out on idle (a pain in the arse in traffic lights) poor performance untill 7k revs then the power band kicks in.... however, it finds it difficult to climb to faster speeds and loses power... i know its the carb settings but that was then, now the badger won't even start i turn the ignition and you can hear it wanting to work... the exhaust is popping unburnt fuel but it won't quite start.... i need to know the mixture settings for my carb... how many turns from the right because it needs sorting... i need the bike asap because i've just lost my job due to credit crunch :s thank you very much.... p.s i heared about this forum because some of you was at mc donalds in southport when it broke... and you was nice guys
What size carb is it? the 28mm or the 34mm? also, what performance mods have you done? It makes a difference to the jet sizes you may need.
i'm not sure... i've not had any modifications and its completely standard.. im goin to assume its 38
What year is the RS if its stock, it should have a stock exhaust, stock air filter and stock carb (28mm) let me know this info and ill find out what the jetting setup should be.
Standard settings for the RS125 of your year should be. Main jet - 120 Starter jet - 70 Needle - 25/3a Mixture screw - 2 turns I would suggest resetting the mixture screw back to standard setting, see if it runs well. Do a plug chop and see what the state of the plug is. If it's white then its lean, turn out the mixture screw to richen up the bike, try with half turns.. eg 2.5 turns out. If its black and sooty, turn the mixture screw inwards by quater turns at a time.. eg 1.75 turns Remember, the RS can be prone to hot seizures.. fuel cools down the engine while its running so if you find the plug is a tiny bit darker than brown but it appears to be running fine all the way through the rev range, I would leave it well alone! My full power 98 RS was running tiny bit rich and it ran 17000km's on the same piston with no engine troubles. I ragged the living tits off it. Another tip, dont set off on the bike until you have a temperature over 40degrees.. cold siezures aren't fun!
thanks for all your help Main jet - 120 Starter jet - 70 Needle - 25/3a how do I know if its 120 70 25/3? i dont know what they mean :s
Hey, i think i helped you put it in the back of the van??? lol I was on the white Hyosung. if all else fails...and you can get it to southport... go and see "Dennis Thomlinson". He's a LEG END!!! He only deals with 2 pokes and scooters and has been on the scene 30odd years, Not much he cant do with an RS125 Good luck fixing her... im so glad i went for a 4stroke
its only a carb problem and if you know what your doing its piss had loads of issues with my tzr carb,but sorted it in end
