Author Topic: bandit 400 flat spot (Read 2771 times)

tonycox · « **on:** August 28, 2006, 06:39:15 AM »

I have a vvc 1994 400 bandit, when I first had the bike it sounded as though it was running on three cylinders--a trip to a local mechanic sorted it with a carb strip/clean and balance, the bad news is that after a short ride it now has a huge flat spot--2000 too 6000 which takes forever to get through, its okay above or below.
MCN reported this years ago and put it down to carb and cam incompatability, I cannot believe that they are all like this--any ideas??

PitterB4 · « **Reply #1 on:** August 28, 2006, 09:07:20 AM »

Hey Tony -

You may get more/better 400-specific answers (and be able to find them on you own) over in the 400 forum and 400 FAQ.

A mid-RPM flat spot like that is very common in the 400 (I assume it's so in the VV, too). You're sounds worse than usual, though. You'll have to play around with your jetting to fix it. I assume it gets at least a little better as the bike warms up, right? If so, you can get some relief by shimming your needles or moving them up a clip position (if equipped with adjustible needles).

wyntrblue · « **Reply #2 on:** August 28, 2006, 09:13:31 AM »

got no flat spots at all on my b4, on the dyno shes got a flat line all the way through the rev range in every gear :/

tonycox · « **Reply #3 on:** August 28, 2006, 11:38:24 AM »

many thanks pitterb4, I have moved the needle position and whilst there noticed one spring seat missing--this also holds down the needle, I fitted a make shift seat [ washer] and it now drives really well without any flatspot at all---thanks again

PitterB4 · « **Reply #4 on:** August 28, 2006, 05:02:37 PM »

Well.. that was quick!