Redrogueleader Posted February 14, 2016 Share Posted February 14, 2016 I have a cbr 125 and I need some help . It used to do around 60ish occasionally but now Well 6000 rpm and its struggling 40 - 45 mph the carb has been cleaned the air filter sorted and a new plug put in There must be someone who knows what's up Anyone??? Quote Link to comment Share on other sites More sharing options...
fullscreenaging Posted February 14, 2016 Share Posted February 14, 2016 You need to get some red power bands on it. Quote Link to comment Share on other sites More sharing options...
Classickid21 Posted February 14, 2016 Share Posted February 14, 2016 .... sell it buy a big bike problem solved ... go faster stripes ? Quote Link to comment Share on other sites More sharing options...
Classickid21 Posted February 14, 2016 Share Posted February 14, 2016 are you riding it with a K&N and you have a better sparky in there... do you have one of these noisy exhaust's to let the back pressure out ? Quote Link to comment Share on other sites More sharing options...
fq-craigus Posted February 14, 2016 Share Posted February 14, 2016 Ride with a tail wind not a head wind Quote Link to comment Share on other sites More sharing options...
Adam Posted February 15, 2016 Share Posted February 15, 2016 Could be the carb needs setting up. Also have you checked tyre pressures and chain sprocket wear? Quote Link to comment Share on other sites More sharing options...
Joeman Posted February 15, 2016 Share Posted February 15, 2016 I have a cbr 125 and I need some help . It used to do around 60ish occasionally but now Well 6000 rpm and its struggling 40 - 45 mph the carb has been cleaned the air filter sorted and a new plug put in There must be someone who knows what's up Anyone???Same revs in same gear but lower speed, probably the clutch slipping. Quote Link to comment Share on other sites More sharing options...
Redrogueleader Posted February 15, 2016 Author Share Posted February 15, 2016 Seriously no comediens please its not the clutch snd its not the plug Quote Link to comment Share on other sites More sharing options...
RantMachine Posted February 15, 2016 Share Posted February 15, 2016 It's probably just down to the cold, need more anti freeze in your oil. Quote Link to comment Share on other sites More sharing options...
cockercas Posted February 15, 2016 Share Posted February 15, 2016 Que the 'hes not come back/replyed' posts in321 Quote Link to comment Share on other sites More sharing options...
cockercas Posted February 15, 2016 Share Posted February 15, 2016 Cdi unit could be on its way out.Fuel blockage.Its hard to diagnose something with a vague discription. Quote Link to comment Share on other sites More sharing options...
Redrogueleader Posted February 15, 2016 Author Share Posted February 15, 2016 Ok the sound of the bike has changed also some suggested broken reed valve the bike is box standard original exhaustabove 4th gear when it approaches 6000 rpm it kind of chokes this pronlem developed over about 3 days in about 90 miles I know the description isnt good but its the only way to describe it Quote Link to comment Share on other sites More sharing options...
Fozzie Posted February 15, 2016 Share Posted February 15, 2016 What does putting the choke on do? Does it improve or worsen at that speed?Could be something as simple as an incorrect needle height. Running too rich would cause it to flood at higher throttle openings and it would splutter. Quote Link to comment Share on other sites More sharing options...
Redrogueleader Posted February 15, 2016 Author Share Posted February 15, 2016 Choke makes no difference Quote Link to comment Share on other sites More sharing options...
Tango Posted February 15, 2016 Share Posted February 15, 2016 Air intake into the airbox ok?......valve clearances?......any leaks on the exhaust/headers? Quote Link to comment Share on other sites More sharing options...
eastanglianbiker Posted February 16, 2016 Share Posted February 16, 2016 Ok the sound of the bike has changed also some suggested broken reed valve the bike is box standard original exhaustabove 4th gear when it approaches 6000 rpm it kind of chokes this pronlem developed over about 3 days in about 90 miles I know the description isnt good but its the only way to describe itits a 4stroke so will not have reed valve so you can ignore that but it does have inlet and exhaust valves Quote Link to comment Share on other sites More sharing options...
Classickid21 Posted February 16, 2016 Share Posted February 16, 2016 Ok the sound of the bike has changed also some suggested broken reed valve the bike is box standard original exhaustabove 4th gear when it approaches 6000 rpm it kind of chokes this pronlem developed over about 3 days in about 90 miles I know the description isnt good but its the only way to describe it If it was a 2t then maybe but its 4t Quote Link to comment Share on other sites More sharing options...
Classickid21 Posted February 16, 2016 Share Posted February 16, 2016 What does the oil smell like ? Any signs of smoke put your hand over the exhaust check see if it leaves your hand moist. For making your 125cc faster its pointless. The money you spend on making it go faster you loose reilabilty, plus you could be saving the money to do your a2... Buy your self a restricted big bike, i promise you, you will not show any more interest in these tonka toys, i am selling my collection to move up, i should of done it a long long time a go. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.