motor pulses at 3000 rpm

redrocket

Supercharged
Joined
Apr 21, 2008
Messages
363
Location
Naples, FL
I'm riding along at 2800-3200 rpm in 3rd gear with part throttle (almost no throttle) and the bike feels like I'm hitting the brakes in a pulsing on and off. Any ideas? I'm out in the middle of nowhere
 
Had the same issue twice in the past two years. Turned out to be a torn vacuum line and a disconnected vacuum line.
 
It only does it in that rpm range and not in 5th gear. I don't think it's the coils, it would do it all the time. I put some sta-bil gas additive just in case it was bad gas, can't tell if it's any better. I will check it out when I'm riding one up next week.
 
 
I checked all the vacuum lines when I was having my problems, so I know this one!

If you lift the tank, you will see little black pipes running behind the throttle bodies, connected by tee pieces.

Start the bike up, and check every joint for leaks.
 
Red there is one coming from each throttle body like Owl said and there is one coming from the MAP sensor. make sure you did not loose any plugs (caps) as there is also one one each throttle body also.
 
You guys understand I still have an airbox :cry: I'll check and see if I can see it and even get to it without taking everything apart.
 
Lifted tank and saw as much as I could w/o taking airbox off. All the hoses as far as I can see are OK. When I slowly rev it up to around 3000 rpms it starts to miss a little, like a bad tune in that rpm range. Any ideas?
 
Ok thanks for all your help, all is well :lol: 12 minute tune did it again. You guys must think I'm off my rocker (no pun intended) :lol: