Do I need compression releases?
Thread Starter
|
Road Warrior
Joined: May 2009
Posts: 1,760
Likes: 211
From: Manila, Philippines
Do I need compression releases?
I installed the FM 107" kit. When I ordered, I asked if I should have them install the CR. They said no need with the 10.125 compression. The bike tends to not want to turn over, but once it does, usually starts right up. Most often when its hot.
I have a new battery and the heavy duty starter. So wondering if its a good idea to go ahead and put in the CRs. I would have to order the jig (Jims) and have my independent install them as he doesnt have the jig, would probably sell it back to him. (I live in the Philippines and get a break on customs duty so cheaper for me to order parts direct.)
Also, if I have to take the heads off, should I go ahead and use the 0.030 head gaskets instead of the 0.045 as I hear it increases the compression a little. Current is supposed to be 10.125 with the FM kit. Anything else I should consider if they have to take the top end off?
I have a new battery and the heavy duty starter. So wondering if its a good idea to go ahead and put in the CRs. I would have to order the jig (Jims) and have my independent install them as he doesnt have the jig, would probably sell it back to him. (I live in the Philippines and get a break on customs duty so cheaper for me to order parts direct.)
Also, if I have to take the heads off, should I go ahead and use the 0.030 head gaskets instead of the 0.045 as I hear it increases the compression a little. Current is supposed to be 10.125 with the FM kit. Anything else I should consider if they have to take the top end off?
Cams make a difference. I would have had them installed just in case. My 103" with .030 gaskets and Wood 555 cams will start without the releases, but it doesn't like it. Glad I have them.
Extreme HDF Member
Joined: Sep 2006
Posts: 10,114
Likes: 29
From: Vancouver B.C. Canada
Why not? I just built a 107 /10.25:1 pistons last week. I try starting the bike with and without compression release, big difference. With the release valves close, crank the motor and voltage drops to 8.5 volts, draw a lot of amperage for sure. With the release valves open, less than 2 revs and it starts. Trust me, you are stupid not to install MCR while the heads are off the motor. Totally worth it!
Thread Starter
|
Road Warrior
Joined: May 2009
Posts: 1,760
Likes: 211
From: Manila, Philippines
Cams are TW555. I asked if I needed CRs and FM said not needed, wish I would have paid the extra few dollars. Now will have to take the heads off.
Since I will have to take em off, anything else I should consider doing?
I have the following:
FM 107
TW 555 cams
Tmax
Bassani 2-1
Since I will have to take em off, anything else I should consider doing?
I have the following:
FM 107
TW 555 cams
Tmax
Bassani 2-1
Stellar HDF Member
Joined: Jan 2013
Posts: 2,464
Likes: 50
From: Rouses Point, N.Y.
you could drop in a set of s&s 570 easy start cams and use your stock push rods and sell the 555's and adjustable push rods. less down time.
Trending Topics
Extreme HDF Member
Joined: Sep 2006
Posts: 10,114
Likes: 29
From: Vancouver B.C. Canada
Don't you know you can drill the compression release on bike? I have seen people doing it with Jim tool. The stepped drilling doesn't go through the heads, at the end they use a tiny drill bit with a bit of grease. It works!
Cams are TW555. I asked if I needed CRs and FM said not needed, wish I would have paid the extra few dollars. Now will have to take the heads off.
Since I will have to take em off, anything else I should consider doing?
I have the following:
FM 107
TW 555 cams
Tmax
Bassani 2-1
Since I will have to take em off, anything else I should consider doing?
I have the following:
FM 107
TW 555 cams
Tmax
Bassani 2-1
HD Forum Stories
The Best of Harley-Davidson for Lifelong Riders
7 Surprising Harley-Davidson Products that Are Not Motorcycles
Verdad Gallardo
8 Best Harley-Davidson Motorcycles Ever
Pouria Savadkouei
10 Worst Harley-Davidson Motorcycles Ever
Pouria Savadkouei
Killer Custom's Jail Break Is The Breakout That Refused to Blend In
Verdad Gallardo
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Verdad Gallardo
Harley-Davidson Reveals Super Cool Cafe Racer Concept
Verdad Gallardo
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Verdad Gallardo
10 Motorcycles You Should Never Buy
Joe Kucinski
10 Things Harley-Davidson Needs to Fix in 2026
Verdad Gallardo
Elite HDF Member
Joined: Jul 2007
Posts: 4,749
Likes: 16
From: sand mountain Alabama
I have the ss585 quick start cams and the work great. I also have CR's on a 113 they also work well. They can be aggravating at times. I like the quick start cams better.
Both are the SS585 cams. One is chain the other is gear.
Both are the SS585 cams. One is chain the other is gear.
Last edited by dirtdobber; Oct 11, 2013 at 01:03 PM.
