Help with Go Kart and RPMs!

[Gumdroop]

Hey guys. I have a manco 1 seater go kart with a briggs and stratton 5hp. My gear ratio is 1:5 (12T clutch, 60T sprocket with 13" drive wheels) and my kart takes forever to engage the clutch.

I have a brand new clutch on it and it engages correctly if I start out rolling down a hill. I haven't thoroughly cleaned the carburetor yet but I did remove it and spray carb cleaner through it and then run it through the engine.

Is the reason my engine isn't reaching the RPM rated (about 2200RPM) to engage the clutch because my carburetor is dirty?

Im new to all this stuff...lol

 

[B man]

your engine should reach 3600rpm.

 

[Gumdroop]

right I know that. But it takes forever to even reach 2200 to even engage the clutch. Is it my carburetor?

 

[B man]

could be. depends on weight,gearing,and terrain. did you run it with out the clutch? did it rev up higher?

 

[Gumdroop]

I took the rear tire off, left the clutch on and checked if it had the same RPMs and it didn't rev up higher.

But I did notice the throttle isn't reaching full throttle. Seems as the butterfly? (governor?) isn't turning as much as it should. When I press the throttle to the floor it doesn't reach that high of RPMs but when I take my finger and press on the butterfly looking piece all the way it reaches full throttle. How do i fix this?

pics to show you what Im talking about.

(Green is what the throttle cable moves, blue is what the green piece moves, red (butterfly) is what the blue piece moves)

 

[MisterRoboto]

looks like red is the throttle butterfly and you just need to adjust your gas cable to pull it open farther. i think... but im relatively new to this as well heh

 

[Gumdroop]

i tried to do that and couldnt get it to adjust that way without the throttle cable being pulled the entire time, so then when i would start it up, the kart would start rolling lol

 

[CaptCanadia]

make sure your governor isn't messed up and you have proper fuel supply. Check your lines and tank.

 

[jeremybentham]

I'm not familiar with the standard governor set up, but here are some pics.

http://www.small-engines.com/5briggs.html

Maybe one of the rods is obstructed and not moving its full range? Rods may be bent? If the pedal/cable are moving properly (smoothly) problem would seem to be in the gov. linkage rods.

Does it idle smoothly?

You want approx 90 degrees of butterfly travel.

Attached are pics of mine showing full closed and full open for a point of reference. (I know we have different linkages just showing the 90°)

 

[Gumdroop]

make sure your governor isn't messed up and you have proper fuel supply. Check your lines and tank.

I'm not familiar with the standard governor set up, but here are some pics.

http://www.small-engines.com/5briggs.html

Maybe one of the rods is obstructed and not moving its full range? Rods may be bent? If the pedal/cable are moving properly (smoothly) problem would seem to be in the gov. linkage rods.

Does it idle smoothly?

You want approx 90 degrees of butterfly travel.

Attached are pics of mine showing full closed and full open for a point of reference. (I know we have different linkages just showing the 90°)

It doesn't idle very smooth. It seems like something in the governor linkage is sticking. I will take it apart tomorrow and check it out

 

[Gumdroop]

dumbass kid that sold to me had the linkage setup wrong....it WAS sticking. fixed the problem!!!

governor doesnt close all the way so the throttle response is insane, so I added a small spring to keep the governor (butterfly) closed unless the gas is pressed.

 

[CaptCanadia]

darn it I was thinking bad spring but you already figured it out lol.

 

[Gumdroop]

haha yep bad spring!
i fixed that, my father has a "spring drawer" lol loaded with random springs. Ghetto rigged it, but it works better than ever