I have a custom built that I built in 2007. It's got a 100" 4X4 Rev Tech engine in it. It has a brand new battery and starter that I just put in it. I also put a new 45mm Mikuni carb and ignition module in it recently. It's only got 8000 to 9000 miles on it. my problem is that it takes several (sometimes 4-5) hits on the stater button to start from a completely cold start, but once it's started and warmed up a bit it starts usually on the first attempt. does anybody know what could be causing this? I also did a voltage check on it in the off position, on position, start button depressed, and running at 2000 RPM. I was told by a mechanic that the readings were perfect. It doesn't have a fuel pump on it. It's just gravity flow from the tank to the carb. Do you think that could be the problem or something else entirely? BTW it runs absolutely fine while it's running.

 

Does the enrichener/choke work properly?

 

Does it have a compression relief? Might need to add that to help the starter spin it over, especially when cold.

 

The enrichener works as it's supposed to. No problem there. It's a brand new carb. and enrichener.
And the engine wasn't designed to have compression relief. Besides the starter turns it over with no problem. It just won't start on the first try. Like it's not getting something and/or enough of something. I might add that I haven't really been riding it for about ten months because I had to have back surgery. But I have been starting it on a regular basis.

 

Not good for the bike to start it & not ride it. That's a good way to build up condensation into the oil & the crankcase. Best just to let it sit on a battery tender if you don't take it for at least a 20 mile ride.

 

What ignition? Mechanical advance weights not operating freely?

 

^^^This^^^^
A good ignition module makes all the difference with cold starts!!!!!!!!!!!!!

 

It's an electronic ignition. Twin Tec 1005 EX, and it's brand new. I just put it in several months ago.

 

Try holding the throttle open a little while cranking?

 

Not sure about the Rev Tech engine set-up, but all the S&S engines have the ability to add compression releases when your engine is 96" or over in size. Might try a starter relay booster kit to help you out. Or if it's been sitting perhaps clean carb float and add some octane boost.

It likely just needs a good ride to clean it out. Modern gasoline sucks...