Compression Release Confusion
Road Captain
Joined: Jun 2006
Posts: 580
Likes: 0
From: Colorado
As it's the OEM map, and you can't really change it at all, there is no value in looking at it. Once you start updating with maps from your SEPST, you'll then be able to see what values your map contains prior to downloading it into your ECM. You can monitor some engine operating parameters with the SEPST while running, but not all of the static parameters that make up the map.
I've never heard my ACR's open that I know of either as the fuel pump generates most of the noise - I'm just trusting that they are working as they should. Maybe I'll listen more closely next time.
Mark
I've never heard my ACR's open that I know of either as the fuel pump generates most of the noise - I'm just trusting that they are working as they should. Maybe I'll listen more closely next time.
Mark
Road Warrior
Joined: Jan 2008
Posts: 1,752
Likes: 0
From: Indianapolis, IN
Just to add some clarification, I talked to my tuner after he dyno tuned my bike. He said that he turns the ACR off when performing the tune and then turns the ACR back on when he is done with the tuning. So I guess there is a way to do that through the software he uses when he is doing the dyno tune.
Cruiser
Joined: Apr 2006
Posts: 170
Likes: 23
From: KC
It is real easy to see if they are working. Stop on an incline, kill the engine, leave the kill switch on and leave the ignition on. In first gear with the clutch pulled in, let the bike roll a foot or so and let out the clutch. You'll hear the release in each head reset.
Last edited by Spurrs; Oct 30, 2010 at 09:34 PM.
Just to add some clarification, I talked to my tuner after he dyno tuned my bike. He said that he turns the ACR off when performing the tune and then turns the ACR back on when he is done with the tuning. So I guess there is a way to do that through the software he uses when he is doing the dyno tune.
It would make NO sence to turn them off for dyno tuning. Are you sure he didn't mean he disables the knock control for tuning? That's normal but not shutting off the compression releases.
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Ultimate HDF Member
Joined: Feb 2007
Posts: 7,663
Likes: 7
From: Northeast Ohio
I am not aware of any HD that is stock from the factory with ACRs that does not have them enabled. If your bike was stock with them, they are working unless someone has played with the ECM or there is a defect.
