This is a weird kind of issue but an issue none the less. My liner will not start unless I put it in gear and push it forward to cycle a cylinder. If I don't do that it will try to start but won't. When I cycle the cylinder it starts right up? Has this happened to anyone else?
Liner engines have a decompression system consisting of spring loaded pins on the camshaft. You are likely moving the motor to a better starting point between compression strokes when you move the motor. Get it checked out after making sure you have a good charge on you battery. Your decompression system may have a problem.
The compression release is a spring-loaded pin on the cam shaft that will kick open the exhaust valve a little early to release compression and allow the "small" starter motor to get the cranckshaft rolling.% As the camshaft begins to spin the centrifugal force withdraws the pin and allows the compression to occur so the engine can fire.%
If it is the original battery, ~6 years old, it's probably due for a change....OR.....
If you have added lights, it might not be kept at full charge anymore.
I think we've had several riders who needed their decompression "adjusted" though.
I don't believe it is a battery issue because it still attempts to turn over with no effort it just won't fire up. I will explore the decompression though...thanks
Both those things will cause it not to be able to overcome the compression........that is, it actually won't turn the engine over; it goes UMPH and stops.
Both things can also cause it to not turn over fast enough to fire.
Because of the fact that forcing the engine to move a bit seems to fix it, I'd lean toward the decomp valve too.......but it still could be a weak battery, or low on charge.
How old IS the battery ??
Would be a good time to have it tested, even if it is NOT the immediate problem.
Did you every figure out what the problem was? I have a brand new liner / trike with the same issue. You have to move the bike just a little before the starter will engage. I thought it might be something with the Ignition circuit cut-off. It's not the battery. The starter doesn't engage at all unless you give the bike a small push either forward or backswards. I never notice the problem till I happen to be sitting on a completely flat surface when starting up at a gas station!