Compression Release - Is this normal?
Seasoned HDF Member
Joined: Jan 2006
Posts: 11,471
Likes: 2,998
From: Charleston, SC
The older 2010 comp had a tendency to start-clack meaning when the engine started it would fully wind up the comp to one end stop and once the engine started, would rotate the comp back to it's opposite end stop and produce a huge clack/slap noise. That was normal.
What really made the system weak was the starter. Even with the SE comp installed (like the rushmore bikes) the system could exhibited the same minor delay (struggle) while the engine was turning over during starting.
That said, Heat degrades the battery's output and the torque output of the starter significantly. If your battery is getting old it's best to have it checked or replaced.
A worn comp usually makes a bunch of noise and may at times cause the starter to struggle, but if the starter comes to a full stop... check the condition of your battery. That starter needs all the help it can get.
What really made the system weak was the starter. Even with the SE comp installed (like the rushmore bikes) the system could exhibited the same minor delay (struggle) while the engine was turning over during starting.
That said, Heat degrades the battery's output and the torque output of the starter significantly. If your battery is getting old it's best to have it checked or replaced.
A worn comp usually makes a bunch of noise and may at times cause the starter to struggle, but if the starter comes to a full stop... check the condition of your battery. That starter needs all the help it can get.
Last edited by lp; Jun 22, 2018 at 05:35 AM.
Advanced
Joined: Oct 2010
Posts: 94
Likes: 2
From: New Orleans, LA
[QUOTE=criyi Is there any easy fix?[/QUOTE]
The easy things are check, clean, tighten the battery and starter connections. If the battery is over 3 years old, you'll likely need a new one soon anyway.
Put the bike in first, hold the brakes and ease out the clutch. If the compensator is bad, it should let you know with the noise it makes.
Otherwise, start by changing the starter clutch. A bad one makes a racket for sure. The cure is some means of compression release, manual, ACR's, or ez start cams.
The easy things are check, clean, tighten the battery and starter connections. If the battery is over 3 years old, you'll likely need a new one soon anyway.
Put the bike in first, hold the brakes and ease out the clutch. If the compensator is bad, it should let you know with the noise it makes.
Otherwise, start by changing the starter clutch. A bad one makes a racket for sure. The cure is some means of compression release, manual, ACR's, or ez start cams.
Grand HDF Member
Joined: Jun 2008
Posts: 4,012
Likes: 298
From: Central Fl
Make sure your battery has a full charge, A lot of these issues are solved with a properly charged or new battery. As others have suggested it could also be the comp, but for me the battery check comes first. Cheap and easy.
Grand HDF Member
Joined: Jan 2012
Posts: 4,456
Likes: 2,858
From: Oklahoma
The clunk, most likely the compensator, especially if you still have the factory unit. The starter stall is a decrease in starting current caused by an aging battery or battery connections in need of attention. I have an 08 Road King and this starts at about 18 months after after a new battery is installed. No clunk because I have the updated compensator, and the various "tricks" to delay battery replacement work for awhile, but eventually, it is new battery time. Without compression releases, this is the way life is. Anticipate a new battery every couple of years OR spend the money on compression releases and get another season or two out of each battery. I have over 91,000 miles on my scooter and plan to do the starter solenoid rebuild this coming winter to be sure the solenoid is passing as much current as possible and clean the commutator and check brushes. Everything in the starter system wears and contributes to eventual decrease in performance.
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