You need to cut the ignition at full throttle and full speed and not let it idle before coming into the pit.
How? Guy above explained how to do it in a shifter, but I don’t have a quick way to kill the engine on my kart. There is a red “kill” switch wired up next to my battery beside the green starter motor switch, but it has never worked since I bought the kart. Is that switch supposed to cut ignition?
If it’s a two stroke you could cover the holes in the airbox and it will die
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That would defeat the purpose as you’re choking it out with fuel.
Put a ziptie on the plug boot and yank it
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Ka100 is meant to have a kill switch isn’t it? Apparently by grounding the coil? I know here in NZ any electric onboard starting engine must have a kill switch fitted.
The KA does have a kill switch but is often defeated as a potential weak spot. To my knowledge, they aren’t required in the US.
Red button that isn’t the starter button. Grounds out the ignition. It doesn’t always work; the engine might diesel along for a little bit and pump some more fuel through, but it’ll often shut it down immediately.
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How should I troubleshoot it since mine doesnt seem to be working?
Just an observation, but right when the video starts, you can see the fuel line, it looks very clear for having oil mixed in, unless your oil is clear.
I have a hard time believing the 40:1 fuel-oil ratio claim. That just seems insane. Normally, 16:1 for break in & then 20:1 thereafter are typical 2-stroke high performance engine ratios, so I’m tending to think that’s your culprit. While there might also be carburetor issues, that seems far too lean a ratio to support a sufficient cylinder-piston oil film boundary layer.
I ditto the lean fuel/oil mix. I always run my mix slightly rich and only mix 1 gallon of fuel at a time. Elf or Motul. I have used the Motul 2T exclusively at 20:1 and only had one piston failure. That was likely due to a crank shaft seal failing on the clutch side. My clutch broke and the puller would not grab the clutch to remove the ring gear in order to replace it. I was forced to use a torch to heat the gear to get it to release from the crankshaft. In doing so I think I may have cooked the rubber seal a little causing it to fail prematurely. The air leak in the crankcase made it go way lean and roasted the piston. When the piston stuck, It broke the crankshaft. After I pulled the clutch cover, I found the seal was destroyed. This was on a Leopard MY09 that used a 3 bearing and the crank was turned down to a smaller diameter to accommodate the extra bearing.
It may just be the mic on the camera, but the engine note sounded a little off compared to other videos of the KA100s I have seen. I can only describe it as a dry pop versus a wet pop in the exhaust note. Could just be me or like I said, the mic.
I try to be cautious with using “rich” terminology when it comes to oil ratios because I see this catch people out. More oil is equivalent to jetting down/leaning out, however the additional oil can trick people into thinking they are (Jetting) rich because there is more oil present in the exhaust etc.
For that reason I avoid using the term rich or lean when it comes to oil ratios. I’ve seen to many people lock up a motor because they thought it was “rich” based on plug color.
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I can understand the confusion. On the leopard I would add 8 oz of oil to 1 gallon of fuel. On the RoK, manual says 5% which is 6.4 oz of oil to 1 gallon of fuel. 0.4 oz is difficult to measure without a graduated cylinder, so I usually eye the 6 oz on the side of the jug and add a pinch for good measure.
This is why I specified the type of ratio as fuel-oil, & not fuel-air. But I get what you’re getting at. It can be confusing to someone if they don’t understand the distinction. I like to think of it in terms of a fixed volume pie chart composed of 3 pie segment: fuel, oil, & air. Adjusting the fuel-oil ratio changes the size relation between just those 2 segments of the pie chart (by adjusting how much oil is premixed with the fuel). Jetting adjustment controls the volume of fuel, altering the combined size of those combined segments in the pie chart relative to the volume of air (by adjusting carburetor jetting).
The ratio didn’t matter in this case. They were running Red Line 2-stroke oil. I’d rather run Filippo Berio Extra Virgin Olive Oil than Red Line; at least there’d be some viscosity.
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Not enough oil. Use 20:1
Also, that change will lean the fuel mixture a little (more oil means less fuel) so you might have to jet a touch richer.