Spark plug barely clears top rod..?


New Member
Jan 6, 2018
Bought this exact kit (with bike) here:

I'm mounting the engine, and am finding that the spark plug (without the wire attached) barely clears the rod across the top of the mountain bike. I feel I will have to mount it slightly leaning to the left or right to have clearance to put the spark plug wire on, which I know will not be good for the chain. OR I could lean it forward or back a bit but then the air intake manifold will not be parallel with the ground as the instructions indicate.

I wish that the spark plug leaned forward more, like in the picture of the kit.. then it'd definitely not nearly touch the rod across the top of the bike. (seems this might have been an issue before and has since been corrected, but apparently not on my engine)...

If I remove the spacer between the engine and the seat rod, the engine goes too low on the bike and might interfere with pedaling. Any suggestions? Just a picture of this motor installed on this bike would be helpful but even the site doesn't have one.. :-/

Thanks very much! First installation but DEFINITELY not my last!!

Larry Trotter

Active Member
Nov 26, 2017
You can cut some off the spacer to lower the engine. You can also go to a lawn mower shop and buy a very short sparkplug that is about 3/4 inch shorter than a standard plug that may solve your problem Larry


Active Member
Jan 8, 2016
Mpls Mn
You could also flip the head so the spark plug is at the opposite angle. That helped me on a columbia bike build once. Doesn't matter to the engine. Maybe the head can be flipped sideways?


Well-Known Member
Sep 30, 2012
a pic would help - if head has slanted plug, try turning it around (sideways is not an option) - otherwise, there is a very stubby plug that works in these, but sometimes even then one can not get a plug tool on it to tighten it