Rear cylinder shutdown........Only if you set it to do that. The default setting is to leave both cylinders on at all times. Which is the way I have mine set. If I get stuck in traffic during the summer, I'll switch it on. Takes 2 seconds.

 

My thoughts exactly!

Mine starts immediately, stock pipes have the low throaty rumble (without waking the neighbors when it starts up), but hit the hammer and the exhaust really roars.

Love it!

 

So is there just a switch you flip or what?

 

My 2011 RGU starts just fine and sounds good when starting.

Besides who cares what your bike sounds like when it starts...as long as it starts every time...LOL

 

Haven't noticed it on my 2001, guess I need to listen a lil better

 

You rotate the throttle forward and hold it for a couple seconds when in neutral idle, it'll activate it and you'll feel the rear cylinder stop firing.

My 11 with the 103 cranks over kinda slow too, I understand the complaint. It always starts fine but it cranks slower than I expected, especially compared to the other non-Harleys I've owned.

I'm sure some of it is related to the starter spinning the primary chain over instead of just the engine itself. That's a lot of mass for the electric motor to turn.

 

You will also get a light on the tach,

Also 1 of 3 conditions must be met for the rear cylinder to stay off

Clutch lever pulled in

Trans in neutral

Throttle less than x %

Any of those 3 prevent you from taking off on one hole

 

Mine sounds great! A lot better than my 2007 which sounded like the engine/starter was falling apart.

 

I hurd dat! My 2007 groaned over so slow I was sure it was gonna strand me. Always caught on the second rotation, but dang!

I actually used the rear cyl cutoff and it is very transparent. Plus it makes it lope like it's 69 Chevelle, GRIN!

 

This is what Harley says...

Automatic Compression Release:
Automatic Compression Release (ACR) valves reduce the strain of starting your high performance motor by reducing cylinder compression - automatically! The engine is easier to turn over resulting in less wear on your starter and battery. After start, the ACR valves close to restore full compression. ACR give you peace of mind and protects your investment. ACR can be installed on stock or Screamin' EagleŽ Performance cylinder heads for all '07-later Twin Cam equipped models. Install requires machining to be performed by a competent machinisht using the Screamin' EagleŽ Automatic Compression Release Fixture Kit P/N 94648-08 (sold separately). Installation requires separate purchase of model specific ACR Wiring Harness P/N 70623-06 or 70623-08.

28861-07A


Fits '07-later Twin Cam equipped models. Can be used with Original Equipment or Screamin' EagleŽ Cylinder Heads. (each)