2004 soft-tail with 103 CI upgrade. Hard starting due to engine upgrade. Shop recommends a compression release or some kind of ignition module. I am not a bike mechanic nor pretend to be. When I try to start bike, it seems like the battery just isnt strong enough to start strong. It does start, but sounds weak. What do you recommend for a high output Battery? CCA?

 

compression releases will do the trick. Without them on mine it will stall the starter

 

The Big Crank (Deka, made in USA) is a good choice. When I relaced my stock batt, the BC replacement had 40 more cca than the original. Batterymart.com. Lots of good reviews.

 

Yes, it sounds like compression releases might fix your problem. The engine upgrade might have included new pistons or heads which raised the compression ratio. That's great for performance, but makes it hard for a stock starting system to turn the engine over. Cam choices can play a part in this as well. High compression engines will often use a cam with a lot of valve overlap. That usually helps turn the engine over, but a stock cam with a high compression engine will have a very difficult time getting started.

Jake

Jake

 

same exact issue with my big bore 103. battery checked out fine so i have installed ACRs to solve the problem.

 

I have MCRs on mine...stock battery lasted about 2 years then started to die on me...upgraded from battery mart to the Oddyssey (http://www.batterymart.com/p-odyssey...softail-1690cc) Starts like butter everytime now!

 

did a 107" with heads and compression releases, dropped in a deka big crank since my stock battery wouldn't hold a charge anymore (it was only 2 years old,too), combined they turn the engine over with ease