Author Topic: compression release in RM465/500 head  (Read 2577 times)

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Offline Ktm181

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compression release in RM465/500 head
« on: December 03, 2013, 01:12:03 pm »

Hi Guys,

currently rebuilding an engine, RM465Z, wondering if anyone has fitted a decomp valve to one of these heads and your opinion of how it turned out?
I have just spoken to a guy who advertises on Epay who has done this mod, uses a generic valve of some brand, Universal Engineering Concepts in Healesville name of Deon, anyone used his service and how did it turn out????? RM465 does not have a second plug hole and is limited for space so needs a fin directly behind the spark plug removing and then machined from there, ANY ADVICE MEN???

Cheers, and Merry Christmas to you and yours,
Kt

Offline Gday

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Re: compression release in RM465/500 head
« Reply #1 on: December 03, 2013, 02:06:18 pm »
I got him to do one on my it490 earlier this year- first 490 he had done. Nice job and it works well. Glenn

Offline asasin

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Re: compression release in RM465/500 head
« Reply #2 on: December 03, 2013, 03:59:39 pm »
I know this is going to sound rough but it worked really well. I put a victa lawnmower auto decomp (maybe thats what he uses) into a 85 cr500 head . it worked really well could even restart on the bump if stalled in the forrest on trails etc. They are very cheap to buy from your local lawnmower shop .It has a vacume hose you connect into the inlet manifold. Could kick it over like a 250  ;D
« Last Edit: December 03, 2013, 04:01:59 pm by asasin »
If in doubt ,WIND IT OUT

Offline rtb

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Re: compression release in RM465/500 head
« Reply #3 on: December 03, 2013, 06:41:34 pm »
I have a RM 465 and a RM 500 and neither one needs a decompressor. Get the kickstarter just over top dead and starts every time.
Also have a CR500 1984 and it is a different beast. You definitely have to have it spot on or you can just kick and kick and it wont start. Thinking of fitting an electric start to it!!!
The 1983 YZ 490 we have is really easy to start as the kick starter is nice and long.

Get your ass off the seat and give it a big healthy kick.

Cheers.

Offline Ted

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Re: compression release in RM465/500 head
« Reply #4 on: December 03, 2013, 07:15:25 pm »
I have two big bores. Were hard to start till I was told to rotate the kickstarter one spline forward.
Piece of piss now.
81 YZ 465 H   77 RM 125 B

Offline Ktm181

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Re: compression release in RM465/500 head
« Reply #5 on: December 03, 2013, 07:20:28 pm »


Thanks guys, I agree, not hard to kick over, more concerned with a crook knee AND damaging the actual  kick start!

Kt.

Offline Ted

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Re: compression release in RM465/500 head
« Reply #6 on: December 03, 2013, 08:12:25 pm »
Buy a mate some beers and get him to push start you all day ;D
81 YZ 465 H   77 RM 125 B

Offline Mike52

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Re: compression release in RM465/500 head
« Reply #7 on: December 09, 2013, 09:11:02 pm »
There is an up side to fitting a deco as it takes a lot of load of the complete starting train including the kickerie.
85/400WR,86/240WR,72/DKW125,Pe250c,TC90,TS100,XT250,86/SRX250,XR400r
Friend  struggling up a hill on a old bike at MTMee .http://www.youtube.com/watch?v=cjj6E2MP9xU.