Kawasaki Brute Forum banner
1 - 8 of 8 Posts

·
Registered
Joined
·
5 Posts
Discussion Starter · #1 ·
Got a 2006 brute force 650i I think it is.
All stock besides HMF slip on and dyna tech cdi new battery and air filter. Starts and rides but Back fires threw exhaust on deceleration shoots flames out exhaust. Cleaned carbs and while they were off decided to check valve clearance all was good But the rear cylinder on intake side the rocker arm moves with cam lobe but you can back the adjustment all the way off and it’s tight tight has no play what so ever and it seems to be holding the intake valves down just enough for it to do what it’s doing. Tuck the valve cover off and checked everything it’s nice and clean no wear and the rocker moves free until it’s torqued down!. Any input on this would be freaking awesome!. I traded for it guy said needed carbs cleaned well that’s not the problem. Sorta speak the rocker arm is not going up far enough for the valves to completely close and I don’t know what it is!. Really need to get it fixed thanks. Sorry for long post just need help ASAP
 

·
Registered
Joined
·
5 Posts
Discussion Starter · #2 ·
By the way. Before I pulled it apart it has been apart before kinda looked like fresh silicone on the valve cover couldn’t be a couple months old if that helps. I thought just maybe they put the wrong valve cover on the wrong cylinder? It can not be much the quad ran and drove no smoke no noise nothing just the backfire the hard start
 

·
Super Moderator
Joined
·
14,011 Posts
Most often its because you are on the wrong TDC. The front and rear must be done separately and have different timing marks. You want TDC on the Compression stroke, not TDC on the exhaust stroke. Take both valve caps off on the rear cylinder and the clutch cover. By hand rotate the engine with the primary clutch on the normal direction until you see the intake valves go down. Then slowly continue until they come back up again and stop. From there it's 1/2 a revolution to TDC of the compression stroke so make a mark on the bottom of the clutch if you have to and continue rotating until that mark it at the top. That is close enough to adjust all valves on THAT cylinder as you have about 30 degrees either side of TDC to do so. Then do the same operation to the other cylinder if you with. Also know valves are set dead cold...that is the engine can not have been run at all in at least 6 hours. As for popping through the exhaust, that usually means a lean condition, low back pressure condition, a blown exhaust gasket or leak somewhere close to a head or burned exhaust valve.
 

·
Registered
Joined
·
5 Posts
Discussion Starter · #5 ·
Alright I think we figured it out I got them adjusted .15mn on intake and .25 on exhaust. Also cleaned carbs and replaced jets etc. the front carb seems to be working properly the rear carb on the inside I guess u can call it the slide we’re the needle is it does not slide up and down when u hit the throttle?. The diagram gasket looks okay caps on tight. It’s one issue after another it may have been the rear carb all along I’m not sure it’s like it don’t have vacuum to it. What is the correct setting in the carbs air screw wise 2 1/4 turn or 3 1/4 I’m not 100% sure
 

·
Super Moderator
Joined
·
14,011 Posts
Alright I think we figured it out I got them adjusted .15mn on intake and .25 on exhaust. Also cleaned carbs and replaced jets etc. the front carb seems to be working properly the rear carb on the inside I guess u can call it the slide we’re the needle is it does not slide up and down when u hit the throttle?. The diagram gasket looks okay caps on tight. It’s one issue after another it may have been the rear carb all along I’m not sure it’s like it don’t have vacuum to it. What is the correct setting in the carbs air screw wise 2 1/4 turn or 3 1/4 I’m not 100% sure
Those are the AFs or idle mixture controls. They will be anywhere between 2.25 and 2.75 turns out from the stop or shut position. More then that may indicate a problem and over 3 turns is pointless. CV slides get their vacuum from a hole under the slide as the air rushing between it and the body causes a low pressure area and thus pulls up against the spring. If it doesn't move, then there is a problem either with the diaphragm, the air bleed orifice is missing or the slide is stick or binding in the track...or the seal surface isn't sealing for some reason.
 

·
Registered
Joined
·
5 Posts
Discussion Starter · #7 ·
What exactly is the air bleed orifice ?. I broke the plastic cap that goes on it last night trying to find a new one of those
 
1 - 8 of 8 Posts
Top