Hey guys, i was wondering whether someone can give me some advice on a problem im experiencing on my bruteforce... When i accelerate from take off it seems to have a flat spot, where it seems to me that it gets flooded, idle very low for a few seconds then it takes off.

im always losing drags i have with my mates due to this.. haha

Anyway, any help would be greatly appreciated, thanks [img]i/expressions/face-icon-small-smile.gif[/img]

 

Has it been sitting unused for a while? If so it may be the carbs are gummed up or old fuel. Have you done any maintainence on it (i.e. plugs, air filter an so on)? Any Mods?

 

Have you done any modifcations to this atv? Such as different exhaust? If so, and you didn't rejet it that might be causing your problem. I'd look at the spark plugs to see if its running to lean or to rich, that will tell you alot.

Spark Plug Color Chart

It's either dirty carbs, bad jetting, bad plugs, or something wrong with the ignition system.

Make sure the air filter is clean too... it it can't suck air it can't make power.

 

Not a tech or anything but you may be running a little on the rich side.
That would explain the low idle (stumbling on the fuel your dumping into it.)
Then it takes off once it get enough air in the mix. This will also cause plugs to foul.
Which also has some off the same characteristics as the problems that you are having. Worst of all you may have both issues.
I have got a couple of friends with V-twin bikes and they are bad at fouling plugs.
When you ride it you have to let the engine get up to temp before you shut it off.
this info came from a CAN-AM Mech. Not saying his word is gold but I trust him.
Good luck hope you get it running good, I hate loosing too. HA HA!

 

Is the flat spot at first initial take off or from a dead stop?

Mine was doing that and the clutch & belt adjustment was off.

Should stand right up on 2 wheels if it is working properly.

 

many thanks for getting back to me guys [img]i/expressions/face-icon-small-smile.gif[/img]

I havent done any mods to it, and it hasn't been sitting unused.. gets used every 2 weeks atleast.
But ill try looking at the above suggestions..

Ill let you know how i go, cheers!

 

Sorry i did forget to mention... that when the choke is on i hasnt got any flat spot, it takes off normally.

 

Try cleaning the carb first, cheap and might be the problem.

 

<div class="FTQUOTE"><begin quote>Originally posted by: kawasakiiii

Sorry i did forget to mention... that when the choke is on i hasnt got any flat spot, it takes off normally.</end quote></div>

That means the carburetion is lean. It's not really a choke on your 650 even though it's called a choke. Actually it is fuel enrichening system - small spring loaded plunger for each carb. To fix correctly (instead of riding with choke on), you need to adjust the carb to richer setting if this was like this from the beginning.