my friend was try to pull a motorcycle out of some mud with his 2000 z400 and he was poppin the clutch, then it would catch in low rpms but when u rev higher it doesn't accelrate i think it slips any solutions?

 

Maybe need new clutch plates, 2000 Z 400 or typo?

 

sounds like you need a new clutch to me, easy to install

 

It's very possible you might just need to adjust the free play in the clutch....I had a
similar problem a few months ago with my Z...Took it to my mechanic and I felt like an idiot..
He showed me how to adjust free play and the clutch worked great and has for months...
I did end up replacing my clutch plates just as a precautionary measure about a month ago, but the free play
adjustment fixed the problem you described...