Predator 212 hard to start + rip your arm off

Np02

New Member
#1
I posted on the diygokart forums here: http://www.diygokarts.com/vb/showthread.php?t=40716

I have a 212 with no governor which requires a lot of pulling force to start, while also every once in a while will fire and engage the recoil starter and pull it back with a lot of force, and I am all the while holding on to it tightly and pulling in the opposite direction trying to start it. (ow.) I don't have a lot of knowledge on engines and turn the forums for help. Could it be something with the timing or compression relase? I just would like to be able to start it sitting in the seat without tearing something in my arm. appreciate any help
 

chrisr

Active Member
#2
Some cams have the compression release which makes pulling over the engine easier and excessive advanced timing can cause kick back.
 
#5
I posted on the diygokart forums here: http://www.diygokarts.com/vb/showthread.php?t=40716

I have a 212 with no governor which requires a lot of pulling force to start, while also every once in a while will fire and engage the recoil starter and pull it back with a lot of force, and I am all the while holding on to it tightly and pulling in the opposite direction trying to start it. (ow.) I don't have a lot of knowledge on engines and turn the forums for help. Could it be something with the timing or compression relase? I just would like to be able to start it sitting in the seat without tearing something in my arm. appreciate any help
check the valves and timing, if its mis firing they could be off (i also have to give it a bit of throttle for it to start sometimes)
how much oil is there? you could have overfilled it and the crank is getting hit with the oil (could also be the cause of the kick back)
as far as making it a bit for comfortable to start, try rotating the pull start so its vertical, that should made it so you can start it sitting down (i cant do that as mine is rivited, but your should be a 8 or 10mm, 5 bolts removed and put back, not that hard)
hope this helps!
 
#7
Make sure when you set your valve lash that you did not set the exhaust valve on the compression release. Sometimes I set it when the engine is a few degrees past TDC, in the ignition stroke. This is so you know you aren't on the compression stroke, where the compression release lives.
 
#8
Have you added a billet rod and flywheel to the engine? It's a good idea to do so for safety when removing the governor.

I've personally watched a chunk of rod shoot about 30' away from a bike when it decided to let go. Left a nice hole in the case too.
 

jayJams

Active Member
#9
my tillotson 212 has insane kickback and it whines while running i removed the governor and put a mikuni on it,i put a screw in the governor arm hole and i think there may just be too much pressure but idk help would be appreciated
 
#10
Describe kickback? If it is pulling the rope out of your hand while pulling it first thing is to turn off the run switch then try pulling it like you do when you start it. If it still pulls the rope out of your hand then it is not kickback but too much compression. The only way that can happen is if your exhaust valve lash is not set correctly and is too loose. Then the compression release will not work.
 
#12
This is a very common problem on this forum. Do you understand how the compression release works? It works on centrifugal force and is engaged until engine rpm increases and a little arm swings out to disable it. When you are starting the engine it will keep the exhaust valve open until about 20 degrees before TDC. If you do not set your exhaust lash at TDC on the compression stroke (or to be safe a little after TDC) you will be adjusting the exhaust lash on the compression release and it will disable the compression release as when it gets to TDC the lash will be loose. It could also be the compression release is broken and if you rev your engine a lot over 8000 rpm then they will eventually break but I assume this is a stock motor.
 

jayJams

Active Member
#19
ok im back the valve lash was broken bought a new one now im having real kickback it doesnt kickback with killswitch in off position but it does kickback in on position plzz help
 
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