General repair and servicing

Information relating to the Matchless G2 or AJS Model 14 250cc Lightweight
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General repair and servicing

Postby Janet » Sat May 07, 2011 6:22 am

Richard, using a TDC tool worked for me as it holds itself in place, so I need one less hand, and it lines itself up the same way every time so any recorded movement will also be the same.
Mine will sometimes spit back through the carb. This is usually after it hasn't been run for a while and becomes reluctant to start for some reason. My guess is that frequent kicking over results in an excess of fuel in the cylinder which finally ignites with a big bang. Since it comes through the carb I assume that the inlet valve isn't sealing properly at the time. Since this happens rarely, I'm not taking the engine apart to have a look.
I take this positively. When my dead engine finally coughs or bangs, even in a way it shouldn't, at least it shows an improvement and a position from where I can gauge the result of further adjustments.
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General repair and servicing

Postby uncle rod » Sat May 07, 2011 9:29 am

Hi Richard, me again when I first tried to start my G2 I was pressing on the kickstart to get the engine on comp stroke ready for the big stomp, now unless I gave it a confident stomp it would fire just as I touched the kick start and nearly take my foot off. so now I wear my boots and just give it a big poke wherever it is and it usually starts first or second prod, hope this helps we are all rooting for you.
Regards Rod

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General repair and servicing

Postby 1923richard » Sat May 07, 2011 9:47 am

Someone told me that it should only ignite every 2nd time it is on TDC? Pushrods are free on top stroke. I am now thinking that it might not get enough fuel as it does not have a choke?
Richard

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General repair and servicing

Postby SPRIDDLER » Sat May 07, 2011 11:34 am

quote:
--------------------------------------------------------------------------------

Someone told me that it should only ignite every 2nd time it is on TDC? Pushrods are free on top stroke.
--------------------------------------------------------------------------------


Correct.
The 4 cycles are:
1)Suck -Piston going down from 1st TDC. Inlet valve open, zorst shut.
2)Squeeze -Piston going up from BDC. Both valves closed. Pushrods free to turn.
3)Bang -Piston driven down from 2nd TDC. Both valves still closed. Pushrods free to turn.
4)Blow -Piston going up to 1st TDC(above) from BDC. Zorst valve open.

Voila!
(You can slow the animation down using the bar under the graphic)

http://www.animatedengines.com/otto.shtml




Edited by - SPRIDDLER on 07 May 2011 11:35:41 AM
I poke badgers with spoons.....from 2 metres.

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General repair and servicing

Postby Janet » Sat May 07, 2011 11:44 am

quote:

Hi Richard, me again when I first tried to start my G2 I was pressing on the kickstart to get the engine on comp stroke ready for the big stomp, now unless I gave it a confident stomp it would fire just as I touched the kick start and nearly take my foot off. so now I wear my boots and just give it a big poke wherever it is and it usually starts first or second prod, hope this helps we are all rooting for you.
Regards Rod

Mine will start without a huge boot. In fact, It's the only bike I have that I'll happily start whilst wearing sandals*. Because I have short legs and it has a long kick-start lever I can't kick it properly from the top of its stroke, so have to move it down to almost level before giving it a prod. Sometimes it will start as I'm getting it into this position, so I think I must have something set up right. Or maybe it's wrong and I should have to give it a big boot.

*I lie. It's the only kick-start bike I'll start whilst wearing sandals.


quote:
I am now thinking that it might not get enough fuel as it does not have a choke?
Mine doesn't have a choke but flooding the carb will usually do the trick on first start of the day.
quote:
Correct.
The 4 cycles are:
1)Suck -Piston going down from 1st TDC. Inlet valve open, zorst shut.
2)Squeeze -Piston going up from BDC. Both valves closed.
3)Bang -Piston at 2nd TDC. Both valves still closed.
4)Blow -Piston going up to TDC from BDC. Zorst valve open.


Then there's
1)Suck
2)Squeeze
3)Bang
4)B****r


Richard,

Keep trying and you'll get there.
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General repair and servicing

Postby spindle » Sun May 08, 2011 7:29 am

spark 1/4 BEFORE TDC
Check your Valve clearance You must warm the engine first to obatain the correct Measurement the push rods are made of alloy and expand when warm, making adjustment when cold incorrect

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