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Decompression Valve....do I have?

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Old Jun 15, 2008 | 12:23 AM
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Default Decompression Valve....do I have?

Hi
I am running a 113" S&amp\\;S motor that the previous owner installed. He showed me a switch that was for a decompression valve. This bike seems to have lots of compression and I cant tell if the bike runs diferent with this switch on or off. How do I tell?
I have a brand new battery in the bike too. If I dont start it all week I may have a hard time getting it to crank over!!
Is there such a thing as a decompression valve on a Harley? How does it work? How do you test it?
&nbsp\\;
Thanks
 
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Old Jun 15, 2008 | 05:32 AM
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Default RE: Decompression Valve....do I have?

Look in the center of your rocker boxes,if there is a 1" or so hole and you see a wire,yes you have electric decompressions.Check it, crank motor with switch in each position notice a difference.Most electrics are wired to starter switch.good luck
 
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Old Jun 18, 2008 | 09:32 PM
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Default RE: Decompression Valve....do I have?

Ok, so my fuse is blown to my decrompression valves. After tracing a perfect ground on the power wire I found that my front decompression valve is shorted and allowing the power to go straight to ground a blow the fuse.
How do I replace this valve? From the top there seems to be a rubber cover over it. Does that just pry out? The motor is a 113 cu in S&amp\\;S.
No wonder I cant get the bike cranking!!
Thanks for the help.
 
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Old Jun 19, 2008 | 12:20 PM
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Default RE: Decompression Valve....do I have?

If it is an S&amp\\;S Decompression valve you will need their special socket or make one that will let the wires come up through it.You will need enough clearance above the rocker box to lift it out.They are approx 3" tall.Good Luck
 
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Old Jun 20, 2008 | 11:23 PM
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Default RE: Decompression Valve....do I have?

Thanks.........new compression release valve on order.
Plus I am going to re-wire it to activate with the start button. It was wired on a switch.....must have burnt it by leaving it on for too long?
Any idea what size socket? id like to pick up a few cheapies next time Im at the hardware store so i can try and make one for the wires to pass thru.
&nbsp\\;
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Old Jun 21, 2008 | 10:00 AM
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Default RE: Decompression Valve....do I have?

1" thin wall 6 pt.Have seen sockets with a hex on the ratchet end that would do the trick for the wires.My releases are wired to the starter wire.No hassle, good luck.&nbsp\\;Mike&nbsp\\;
 
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Old Jun 29, 2008 | 09:21 PM
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Default RE: Decompression Valve....do I have?

I got the compression release valve changed no problem.
It was originally wired to an on/off switch. I thought maybe the switch was left on and the compression release valve burnt out.
Here is my problem....I tried to wire it into the starter circuit to activate with the start button. I have a solenoid starter similar to this. http://www.chopperscycle.com/page/VT...-180-113/30027
There is a connector on top of the solenoid that has power when the starter button is pushed, so i thought that would be an ideal place to wire in the cmpression release valves. When I wired it and activated the starter, it caused the start solenoid to stick. When I pulled the wire off and re-tried, it was fine. I tried it a few times and when the release valves are wired right from the solenoid, the solenoid sticks. I wonder if i can use that connector to activate a relay. Or, if I continue to use a switch to active the compression release valves, how long can power be continuosly applied to them before they burn out? It would suck if I forget to shut them off!!
 
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Old Jun 29, 2008 | 10:55 PM
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Default RE: Decompression Valve....do I have?

Ok, I even tried a relay. I tied into the top terminal on the starter (I only have a pushbutton and no relay) It seems that when I connect to this terminal and push in the button, it wont release the plunger!! I guess I will have to wire the on/off switch back for the release valves and hope i dont forget them on!
 
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Old Jun 30, 2008 | 06:02 AM
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Default RE: Decompression Valve....do I have?

Curious? Mine work great never had a problem.S&amp\\;S tells you to wire at the starter switch wire.You say you hit the button and you hear them open? If yes that is a good thing.The&nbsp\\;compression will slam them closed.
 
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Old Jun 30, 2008 | 06:24 AM
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Default RE: Decompression Valve....do I have?

Wire it to the input wire of the starter relay, not the starter solenoid.
 
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