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decompression valve any experience ??

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Old Mar 30, 2025 | 12:07 PM
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Default decompression valve any experience ??

Hello to everyone. I have 66 ironhead. Kick start only and the problem is that I am small and old so starting that became a challenge.

In order to solve that I found out there exist something called decompression valve but there is not much information about that. How that works how to use that.
My problem to start that motorcycle is the compression so .... will that solve that problem ??
I knows nothing about those valves so any help is welcomed.

 
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Old Mar 30, 2025 | 01:20 PM
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They should help in theory. It’s basically a 10mm hole drilled into the head and threaded. The release is screwed in and when pushed down allows air to escape on the up stroke. When the bike fires the pressure closes them although sometimes it takes a throttle rap.

I don’t need them on my iron head yet but I have a set on my fat boy with the 95”.
 
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Old Mar 30, 2025 | 02:32 PM
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To find them its called compression release valve
 
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Old Mar 30, 2025 | 03:16 PM
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Originally Posted by 03fattyaz
They should help in theory. It’s basically a 10mm hole drilled into the head and threaded. The release is screwed in and when pushed down allows air to escape on the up stroke. When the bike fires the pressure closes them although sometimes it takes a throttle rap.

I don’t need them on my iron head yet but I have a set on my fat boy with the 95”.

Thanks
sounds like the solution I need.
I can kick several times till the engine fires. That is great.
Just one more question.
If the valve does not close can I pull it back to close that ?

 
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Old Mar 30, 2025 | 05:09 PM
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We can fix small and old a little bit. I'm 75 with a 77 XLH 1000, kick & electric start. I've been relying on the Magic Start button for few years now. Recently I found a STROKER KICKARM. 1 1/2 inches longer than OEM. Wisco 10:1 forged pistons, Andrews R5 cams, not good for a kicker.

Well, after 2 mini-strokes, Afib and a triple bypass I can kick it again!
 
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Old Mar 30, 2025 | 07:02 PM
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That is another good idea
where did you find the longer kick arm ? mine does not have electric start so I have to solve this.
yours also have a oil pressure gauge on the rear cylinder head. Where did you find that ?
 
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Old Mar 30, 2025 | 10:11 PM
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Originally Posted by sivi8272
Thanks
sounds like the solution I need.
I can kick several times till the engine fires. That is great.
Just one more question.
If the valve does not close can I pull it back to close that ?

Yes but it’s easier to just blip the throttle.
 
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Old Mar 31, 2025 | 07:16 AM
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Stroker Kickerarm that I am using is from Drag Specialties, forged steel. The oil pressure gauge is a V-Twin item. Might wanna take a look on ebay and see what pops up.
 
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Old Mar 31, 2025 | 04:59 PM
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Yes
I found the longer arm. Thanks
I also found at eBay the oil gauge.... the gauge goes from 0 to 60 psi ..... looks to much for my motorcycle.
Reading more carefully it is for models from 71 to 84

my 66 model may not have that level of pressure I think
 
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Old Apr 1, 2025 | 03:27 AM
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0-60 is fine for your `66
 
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