I understand the benefits of the auto compression releases, just a bit confused on when they're needed.

When I upgraded my Fat Bob to the 103 Stage II, I asked about adding them, and the tech told me they weren't necessary on the 103 Stage II. Got the bike back, never had an issue.

Now I see they're coming on the 2010 103's (w/o cams) with them already installed. Is that really necessary? Is it just peace of mind? I'm getting ready to upgrade my 2012 to 103 Stage II and I want to make sure I'm not tempting fate by not adding them.

 

Wouldn't say there a must have but you'll probably notice on a hot day with a hot motor 103 and upwards have occasional difficulty turning over with ease. Compression releases help that process. In bigger motors perhaps 110 and up I can see them being a must have item.

If your going to do cams anyway take a look at S&S easy start cams. In short they allow a valve to stay partially open on crank up allowing compression to be reduced for the moment until she fires up.

 

When cranking compression gets up north of 190psi, compression releases are nice to have and will extend battery and starter life. The closer CCR gets to 200psi, the more important the releases become and anything above 200psi should definitely have compression releases. I have seen a crank shift as the result of a nasty heat soaked kick back on a hot summer afternoon. If the guy had CRs, no problem.

As an example, if you upgrade to 103 Stage II with SE255 cams, your cranking compression will be about 198psi, definitely CR territory. However, if you install say the Woods 555, static compression will stay at 9.8 but CCR will drop to 185psi and you could get by without CRs.

 

Doesnt your bike already have them being a '12?

 

I would just get manual cpr's machined in. The ACR's you need a wire harness (60.00) and if you don't have the SERT you will have to have the dealer turn it on in the ECM for you. same price as a stage 1 download. 100.00 min
I'm working on a timer and a wiring harness that will work off the starter relay for the ACR's on my bike. "FTF"

 

 

His sig lists his bike as a 2010 but posts he has a 2012.......hmmmm

 

I fixed the year, mine's a 2010.

 

I look at it as cheap insurance personally. Easier to do it when you have it all apart anyways, and if you ever change your cam down the road it's one less thing to do. That's just my opinion.

 

the problem is that a new a clean engine wont' need them....but...after some carbon build up...the compression goes up and now you need them. Also, the first start of the day is pretty easy on the engine since there is no pressure and the motor spins pretty freely.....but if you pull in for gas and start the bike up again...hot tight bike plus prelaod listers and compression in the engine from stopping just before top dead center...and now you need ACRs or MCRs.

If you pull your heads for anything, might as well send the head sout for MCRs. got mine done for $125 with free shipping back to me.