I own a custom built motorbike (from tyres up) with a Harley Davidson 1340 Evo stock unit engine. It is kick start and I want to convert it to electric start. I have been told that I would require a 5 speed gear box (currently a Rev Tech 4 speed) and a primary drive < 3" (currently 3"). Is this true?

Question edited for full year make model.
Question moved from Cars and Trucks

What causes oil to come out of the breather on a Harley?
Top breathing engines breath, or vent, through the top breather bolts which are threaded into the heads of a Harley Davidson motor. The air inside a motor is saturated with oil. When oil drips out of an air cleaner assembly, it is usually an indication that the air cleaner element is due to be cleaned, or changed.Oct 22, 2019

What causes oil to come out of the breather on a Harley Davidson?

Videos as well

https://www.google.com/search?q=1993+Harley-Davidson+1340+Softail+Custom.+Oil+all+over+underside+of+motor

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make sure you are running the correct plug and wires for your engine and that it is properly gapped. if your piston rings are worn, excess oil burning can foul the plugs. make sure the carb is properly jetted and/or the fuel injection system is properly mapped.

MY 1995 1340 evo roadking oil light stays on at idle when the engine is hot, I've chenged the oil and filter using genuine harley davidson, changed the oil pressure switch and even done a full engine flush with 4 litres of flush oil which as made the oil light stay on until 1200 RPM's, before i flushed the system the light would go off at a round 1000/1100 rmp's.

0.9mm and possibly about 3.5-4.0L w/ filter change

stock bore on a 1340 evo is 3.498" the stroke is 4.250" remove cyclinder head,with piston at TDC (top dead center) turn motor over till piston is at BTC(bottom dead center) and measure that is your stroke

Pull the spark plugs out and hit the starter. This will make sure that the engine is not locked up. If the starter does not turn the engine, put the bike in first gear and have someone push you, making sure the engine is free. If the engine is OK, your starter is probably jammed and needs replaced. That wire getting hot is a dead giveaway something is locked up tight...starter or engine. If ya have a large hi-performance engine in the bike, chances are your stock starter won't do the job.