Hey everyone, I'm new here and am having a problem with my bike. Whenever it hits 4,000 rpm it jerks real bad for a second and then seems to be alright.

I just bought it from a friend of a friend and he said he changed the oil before he brought it here and put synthetic in, could that be an issue?

I've been searching forums and have found a bunch of different answers but not the exactly what I need. I'm trying to see if there is something obvious to check before taking it in for diagnostics. Any help would be greatly appreciated!

Thanks ahead of time!

 

Do you have any mods like a powercommander?

 

ask your friend if he used auto oil because if he did then you need to change it again because auto oil has additives in it that cause wet clutches to slip(which is what you have). this may be your problem or like my man is trying to figure out above it may be a fuel problem.