so i had a family friend clean my carbs out and my bike runs good once i put them back on. however, the family friend told me that my bike was running lean after he did a test ride on it (he is many years my senior and knows exponentially more than me about bikes). dunno how you can tell by just hearing it run, but i also dont know what to listen for. i know running lean refers to the gas/air mixture and that it means there is not enough gas compared to air (feel free to correct me if i am indeed wrong).

so my question is how do i go about correcting this? if i even can. my friend recently had an exhaust installed on his 300z and the mechanic who installed it told him he's gonna be running lean now and to get it changed cause its bad for the engine. my bike does have a yoshimura slip-on that came with the bike when i bought it. i do not have the stock exhaust for it, but could that be why its running lean?

any help here would be great! heres some pics and stuff of my bike https://cbrforum.com/m_114965/tm.htm

thanks!

 

Any time you change something in the intake/exhaust setup you should have your carbs jetted. I can't give you the technical details as to why other than your changing the air/fuel ratio and the carbs should be setup for how you're running it. I was told by a friend that used to race that even changing to a K&N from a stock air filter was enough change to have the carbs re-jetted. FWIW, that is what I have been told. As far as being able to tell it's running lean just by the sound, does your bike backfire when you're downshifting? Running lean isn't necessarily a bad thing. It just depends on how lean.

 

no it doesnt backfire when downshifting. it runs great and starts up in the morning with no choke needed. as far as i can tell everything runs great and there have been no problems thus far i was just worried about the comment that it was running lean. ive been very happy with the bike so far other than that

 

he probably noticed it with higher rpm and speed

 

backfiring could be really lean or nice and rich too! lean will have small lean pops and rich will have loud actually fire out the pipe back fires!

 

haha funny you should say that. i was having petcock troubles (have since been resolved once i took it apart) and while trying to get the bike to run one day i had full choke on and it once it eventually started (on reserve mind you) i revved it up a bit and my friend said he saw some fire come out of the pipe! haha it scared the crap outta him. but like i said, starts up fine now with no choke and theres no backfiring at all. guess i'll just need to look into a jet kit....

btw, how big of a project does putting a jet kit in entail? doable by myself with standard tools etc? thanks guys!