Hey guys I picked up a dyna with a built 124" s&s setup...great bike but whenever the motor is cold (weather below 50 degrees)I just can't get it started even with a new battery. I have compression releases but once it cranks for about 10 seconds its dead. Any ideas on high output battery or starter options? The bike functions perfectly but I feel like there just isn't enough strength to those pistons in the cold.

 

It's carbed, right? What about starting fluid, nothing like an ether kick.

 

What size starter is it ?

 

Why is it cranking for 10 seconds?

What kinda of carb?

Give a twist of the throttle, and pull the enrichener, and crank it. Sometimes 2 twists if it's REALLY cold.

Chase

 

Starter is stock now...problem is that it doesn't have enough power to move the pistons.

 

So, it's cranking slow when cold, and better when hot?

A cold engine is physically easier to crank than one that is at operating temp. Once hot, everything is nice and tight. The oil will be thicker when cold, however, these are dry sump engines.

If it's hard to start after it's all cooled down, and cold out, I would look into the battery first, especially if it's dead after 10 seconds of cranking. I would also suggest looking into the charging system, just to be sure it is up to snuff.

The other thing, a good running, well tuned engine shouldn't crank more than a couple seconds before firing. Turning that big engine over for that long, is certainly not doing you any favors. It'll make your battery and starter worse.

Chase

Edit, try pulling the clutch when starting, and see if that makes any difference.

 

Thanks chase...I think I misspoke. It doesn't take 10 seconds to start the bike. In warm weather it fires right up. I'll look into a stronger battery then stock.

 

I have a 124 in a FXDWG. I'm assuming you have the twin cam engine. Those motors need to be turned over faster. I changed the 10/102 starter/flywheel gearing to 10/84. Also you cant use the Compufire 6 to one starter. It has plenty of power but wont turn over fast enough. I used to have the start problems you talk about. I have a Lightning Start battery, an All ***** 1.6 starter (bigger is not always better), and the 10/84 gear set.
Since I put all that in if starts like a stock bike. I put a switch in where when I activate the decompressors, it kills the lights and all my power goes to the starter. Once it starts I just flip the switch the other way. The way S&S wires the decompressors thru the start relay you can actually feel the decompressors moving up and down as the motor turns over. With the switch that goes away. I spent 3 grand on this problem trying different starters, batteries and what not. What I listed here is the best set up to date.