Author Topic: decompression valve. where from?  (Read 23482 times)

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Offline Mike52

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Re: decompression valve. where from?
« Reply #30 on: June 17, 2013, 09:03:00 PM »
The one shown on my Husky is a Harley aftermarket part.

Over the hill , Push these and they stay open until the engine fires then they slam shut and stay shut until you push them again.
Nothing like the old cable types.
« Last Edit: June 17, 2013, 09:05:52 PM by Mike52 »
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Offline OverTheHill

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Re: decompression valve. where from?
« Reply #31 on: June 17, 2013, 09:36:02 PM »
Thanks for that [Mike52 & others], i'm learning all the time. Triumph 650 twingle's got me thinking, she'd be a beastie to kick over alright. Did an RD350 as a 'twingle' years ago [with dirt in mind] but sold it before i got it running damn it, was close too running too, just too tight to spend money on new piston kits at the time. Your type of de-comp in the head would have been ideal. Thanks.

Offline Tim754

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Re: decompression valve. where from?
« Reply #32 on: June 18, 2013, 11:58:37 AM »
Got 4 x 246cc four stroke pots at 12.4/1 comp all in a line, stuff decompresses. I just refitted the electric starter motor with a couple of extra electrical relays :D

Sorry ::)   Seriously, Have fitted "Vulcan" brand decomps over the years ,never had any complaints, worth the dollars.
« Last Edit: June 21, 2013, 07:09:00 PM by Tim754 »
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Offline Freakshow

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Re: decompression valve. where from?
« Reply #33 on: June 18, 2013, 01:27:48 PM »
I got some on cable and bar levers if any one wants to buy some
74 Yamaha YZ's - 75 Yamaha YZ's
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70  Jawa 2 valve speedway's

For sale -  PRE 75 Yamaha MX stuff, frame, motors and parts also some YAM DT1,2,A and Suzi TS bikes and stuff


Offline Ballterror

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Re: decompression valve. where from?
« Reply #35 on: June 14, 2018, 03:06:53 PM »
Hello, Just wanted to revive an old thread, does anyone know where to purchase the compression valve from these days?

Looking to fit it to a 87 Cr500, there seems to be a lot on Ebay but just wanted to purchase something that is a proven product and the correct size?

Thanks.


Offline Momus

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Re: decompression valve. where from?
« Reply #37 on: June 14, 2018, 09:59:20 PM »
https://secure.vulcanworks.net/store/Compression-Release-Set-14mm-Long-Reach.html

I've fitted a few and have used chainsaw units- Stihl/Husky push button type with the 10 x 1.0 thread; $150 US sounds a bit exxy. Stihl genuine are about $20 or you can get a 3 for $12 with free postage Chinese deal from Ebay.


Getting the unit is easy, the install in a water cooled bike needs a bit of thought. Most I've seen involve a welded boss that the decomp screws into. I make an adaptor using a M6 thread that requires only drilling and tapping and can go through the water jacket.
« Last Edit: June 14, 2018, 10:02:09 PM by Momus »
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Offline Ballterror

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Re: decompression valve. where from?
« Reply #38 on: June 15, 2018, 11:37:15 AM »
Thanks for your help people, much appreciated.