compression check
Outstanding HDF Member
Joined: May 2008
Posts: 2,543
Likes: 19
From: Ashland Ohio
slightly warm. Let it idle for like two minutes TOPS, then check. Squirt a couple drops of oil in the plug holes and spin it. Check it again.
If it is a newer bike, you must pull the fuse or disconnect the wiring for the ACRs. If it is a BAGGER, you must also hold the throttle plate open with your finger or a wooden dowel. Compression needs to be checked with WOT. DBW bikes will NOT open the throttle plate when checking compression.
If it is a newer bike, you must pull the fuse or disconnect the wiring for the ACRs. If it is a BAGGER, you must also hold the throttle plate open with your finger or a wooden dowel. Compression needs to be checked with WOT. DBW bikes will NOT open the throttle plate when checking compression.
Elite HDF Member
Joined: Nov 2010
Posts: 3,846
Likes: 173
From: Simi Valley, CA
The manual says to do it at operating temperature, but like soft02 says, removing the plugs from a hot aluminum head can cause problems. Personally, I would just do it at room temperature. If you're doing the compression check to troubleshoot some problem, chances are nearly 100% you'll find the problem hot or cold.
If you really want to do it hot, I'd remove the plugs first while it's cold, put some anti-seize on the plugs, reinstall and run up to temp. That would minimize any chances of damaging the threads in the head.
If you really want to do it hot, I'd remove the plugs first while it's cold, put some anti-seize on the plugs, reinstall and run up to temp. That would minimize any chances of damaging the threads in the head.
Last edited by 2black1s; Apr 13, 2013 at 08:44 PM.
Thread
Thread Starter
Forum
Replies
Last Post
purcell06
Ignition/Tuner/ECM/Fuel Injection
1
Jan 20, 2006 09:33 AM
