G2 - low compression and little power

Information relating to the Matchless G2 or AJS Model 14 250cc Lightweight
jonhal
Posts: 353
Joined: Sun Oct 15, 2006 5:12 pm
Location: UK

G2 - low compression and little power

Post by jonhal »

Sorry, senior moment, barrel- rich, was thinking about my Arrow. Could be a leak though.
John(very humble)
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crawsue
Posts: 1180
Joined: Tue Apr 19, 2005 1:00 am
Location: GLASGOW UK

G2 - low compression and little power

Post by crawsue »

Hard work never killed anyone.....but why take the risk?
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crawsue
Posts: 1180
Joined: Tue Apr 19, 2005 1:00 am
Location: GLASGOW UK

G2 - low compression and little power

Post by crawsue »

I found that adjusting the ignition while the engine was ticking over made a huge difference to my G5.Open the access plate and slacken off the back plate screw a little--just enough to allow some swivel on the plate then gradually advance the ignition,it should start to tick over a bit faster as you get to the correct setting.Worth a go before stripping off the head.
Hard work never killed anyone.....but why take the risk?
sej
Posts: 13
Joined: Tue Feb 26, 2002 12:00 am
Location: CHESHIRE UK

G2 - low compression and little power

Post by sej »

Hi Buscuit
The timing is set up ok thanks. The carb does fit onto the head via a stub your dead right, and I've made sure its really well sealed, so fingers crossed should be fine.

Hi jonhal
Thanks the the tip, I will keep an eye on the seal once the engine is warmed up.

Hi crawsue
I will try slight adjustment of the back plate as the throttle it not really crisp. It was set it up with a couple of wires and bulb, I will mark that position before I start and tweak it a bit.

Hi Paul
You were spot on with the air valve position, the engine is running much better now. I will try some other suggestions to see how crisp I can get it, I would say its sorted 95%. I will not be able to do any more until the weekend.

Thanks very much everyone, I really appreciate the help.
All the best
Steve
gerry wilson
Posts: 5
Joined: Thu Jun 14, 2007 1:23 pm
Location: UK

G2 - low compression and little power

Post by gerry wilson »

The 25psi compression reading must be wrong, the engine would never start,look through the carb intake to check the position of the choke slide in relation to the lever position. You should always check the compression with the choke off and the throttle wide open, otherwise very little air can get into the cylinder to be compressed.
lawrence
Posts: 2453
Joined: Mon Jan 01, 2001 12:00 am
Location: NORTHAMPTONSHIRE UK

G2 - low compression and little power

Post by lawrence »

Welcome to the site Gerry. Hope we hear more from you
sej
Posts: 13
Joined: Tue Feb 26, 2002 12:00 am
Location: CHESHIRE UK

G2 - low compression and little power

Post by sej »

Hi Gerry

Sorry for the delay in reply, I did not realise I had a message. Really good tip, I think the choke was on when I first checked the compression, I will give it another go.

Best Regards
Steve
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