Rough through first gear

[hatrick32]

Just bought an 09' XB12R and have put about 90 miles on it. Today I was taking my girl around the town and noticed that the bike is extremely jerky throughout first gear (more than usual). Once she got off of the bike the problem remained, any thoughts??

 

[onelogue]

Through what Rpm range?

 

[anrkizm95]

primary chain adjustment

 

[RuiP]

do the breather mod, this is a must with this bike. you will notice an immediate improvement.

 

[hatrick32]

It gets jerky around 6000rpm. Where would I find the breather mod?

 

[RuiP]

ok at 6k rpm the engine is running near full power so you have to be pretty smooth with the throttle, i felt teh breather reroute mod helped with stumbling in the lower revs. If you want to do the mod there is a ton of how-two information in the diy section

 

[anrkizm95]

jerky or surging my 09 surges some times in the higher rpms. the first thing i would do is a tps reset it takes about 30 sec.i usally reset my tps a couple of times a week.

 

[onelogue]

do the breather mod,  this is a must with this bike.  you will notice an immediate improvement.

NOT TRUE!!! My bike does not have the breather reroute and my xb12 isn't rough at all. The bikes were designed to run good without the reroute.
Think of the re-route as a healthy thing for a bike but not a cure for problems.

Describe the jerk, does the bike sound deifferent? Is it the jerky feeling you get when you are at low RPM's? Cause jerking problems ONLY in 1st gear has to be transmission, especially at 6k.

 

[anrkizm95]

^ i dont recomend the breather mod it did nothing at all for my bike except lean it out more than it was.

 

[RuiP]

sorry but i have to disagree, i noticed an immediate improvement at idle and lower rev smoothness. You can have just fresh air being sucked into the combustion process or the stock fresh air mixed with crankcase gases instead, your choice.

not sure how it would lean out your mixture ir you're just eliminating crankcase gases.

 

[anrkizm95]

breather mod will also let crankcase pressure increase since vaccum isnt drawing it out.hcs increased on my bike,hc increase = more air,more air = leaner.

 

[onelogue]

sorry but i have to disagree, i noticed an immediate improvement at idle and lower rev smoothness.  You can have just fresh air being sucked into the combustion process or the stock fresh air mixed with crankcase gases instead, your choice. 

Than explain why my bike can run at 1200rpm with little to no jerk sucking in lots of crankcase oil and gas.
A high rev jerk in 1st gear. is way more than crankcase gases going through the intake.
Lets try to solve his problem before you recommend DIY mods to the guy.


Hatrick32, also besides the questions i asked earlier, how many niles does your bike have? Plugs may need to be replaced if you bought the bike used.

 

[RuiP]

well if you read my posts you'll notice that i wasn't aware that it was occurring at 6k rpm.. not that big of a deal there. I'm sure its the transmission like you diagnosed there o great mechanico. lol

 

[onelogue]

lol

Laughing at yourself for not reading his first post properly?

 

[RuiP]

anyway aside from captain mechanico's online diagnoses and witty quips, I would advise bringing it to the dealer since it should still be under warranty

 

[anrkizm95]

check your primary chain mine was loose from the factory.do a tps reset.those two things will take about 5 mins tops.it would take you longer to warm up your bike and get your gear on.and there free.