103" big bore without compression release?
Tourer
Joined: Aug 2008
Posts: 474
Likes: 3
From: Los Angeles, CA
I did not put MCRs in my bike when I recently went to a 103; but I did add a bigger starter. I was trying to have my bike look like the motor was stock, so I could surprise some folks...I have upgraded the compensator to the SE version, so I'm hoping that will help. I may put in the ACRs later if I experience too many issues.
Ultimate HDF Member
Joined: Aug 2008
Posts: 5,413
Likes: 17
From: eastern oklahoma
when the weather is hot during summer, and the humidity is high is when i've found the need for compression releases. also when you go to the gas station and fill up, get back on your bike with a hot motor along with the aforementioned weather, and if you have high compression it's really going to bang when you try starting it if you don't have the compression releases of some sort, either mcr's or acr's. this was a good thread to start.
Tourer
Joined: Apr 2009
Posts: 336
Likes: 0
From: Kansas City
when the weather is hot during summer, and the humidity is high is when i've found the need for compression releases. also when you go to the gas station and fill up, get back on your bike with a hot motor along with the aforementioned weather, and if you have high compression it's really going to bang when you try starting it if you don't have the compression releases of some sort, either mcr's or acr's. this was a good thread to start.
Cruiser
Joined: Dec 2010
Posts: 102
Likes: 1
From: Canada
I installed MCR's after the first year on my 103 w/255's..Hot starts were an issue..cold I never used them..I had a few problems after the MCR's and ate a starter. Had the bike re-tuned and still had some issues...The cheapest and easiest fix is S&S travel limiters..$20 for the limiters and $40 for gaskets, and the bike never kicks back or grinds the starter down..ever
Ultimate HDF Member
Joined: Jan 2011
Posts: 9,850
Likes: 220
From: Sacramento, CA.
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Road Master
Joined: Aug 2008
Posts: 928
Likes: 0
From: Redmond, WA
Don't have them on my 103" but I didn't touch the heads and didn't have any problems when starting hot during the summer. If I have the heads cleaned up I will put in CR's at that time to handle the increased compression.
Outstanding HDF Member
Joined: Dec 2008
Posts: 2,182
Likes: 0
From: Phoenix
I don't have compression releases. I am considering getting a good Spyke starter though.