Non starting G2 - New owner seeks help.

Information relating to the Matchless G2 or AJS Model 14 250cc Lightweight
mn757
Posts: 30
Joined: Sun Mar 22, 2009 10:24 am
Location: WEST MIDLANDS UK

Non starting G2 - New owner seeks help.

Post by mn757 »

Hi,

I've just bought my first classic bike and its ground to a halt after two days of trouble free riding. It miss-fired a couple of times and then refused to start. I pushed it home and noticed that the bolt the goes through the points cam had come loose. I wondered if this was stopping the points opening / closing but they seemed ok. I have a nice spark at the plugs after checking the points gap, I have fuel getting to cylinder but still it refuses to go.

The two screws that secure / adjust the timing seems to be tight so I dont think the timings out, I did wonder if the points cam had moved out of position (I notice it can fit two ways round) but it seems ok. I'm running out of ideas now and wondered if anyone could offer suggestions.

I have a nice 6 volts at the lead which connects to the points, and the points look healthy (no pitting) and I have swapped the condensor to no avail.

It's a great bike and I cant wait to get out on it again.

Any help greatly appreciated,

thanks

Martin.
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chris kelly
Posts: 288
Joined: Mon Jan 01, 1996 12:00 am
Location: OSTERGOTLAND SWEDEN

Non starting G2 - New owner seeks help.

Post by chris kelly »


Hi Martin,
Welcome. What year is your G2 please?

Also what spark plug are you using....I know that you are getting a good spark...I am just thinking of a situation I had on my AJS14, 1966 Model.

Best wishes,
Chris.
'My cat can beat up your cat!'
itma
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Joined: Tue Nov 22, 2005 6:01 pm
Location: UK

Non starting G2 - New owner seeks help.

Post by itma »

If the centre bolt has come out I think you can take it as read that the timing has also gone up the swannee.
re time it and try again
mn757
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Joined: Sun Mar 22, 2009 10:24 am
Location: WEST MIDLANDS UK

Non starting G2 - New owner seeks help.

Post by mn757 »

Hi, thanks for replies. It's a 1960 model. I'm using a BP7S spark plug from memory. I was hoping the timing wasn't going to need resetting, it looks a bit awkward. Does the central bolt do anything other than hold the points cam ?

many thanks

Martin.
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davehutch
Posts: 192
Joined: Sat Jul 19, 2008 4:05 pm
Location: LEICESTERSHIRE UK

Non starting G2 - New owner seeks help.

Post by davehutch »

quote:
Hi, thanks for replies. It's a 1960 model. I'm using a BP7S spark plug from memory. I was hoping the timing wasn't going to need resetting, it looks a bit awkward. Does the central bolt do anything other than hold the points cam ?

many thanks

Martin.

It just holds the point cam
----Only a biker knows why a dog sticks his head out of a car window.
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chris kelly
Posts: 288
Joined: Mon Jan 01, 1996 12:00 am
Location: OSTERGOTLAND SWEDEN

Non starting G2 - New owner seeks help.

Post by chris kelly »


Hi,

Okay, I had just thought your bike might have been a later CSR.


Presume you have access to manual....and withdrawal bolt part number 042247 if you intend to remove the unit to reset ignition timing.

Just noticed a ''note '', in my literature, ''The contact breaker cam is detachable and if it is inadvertently removed, the timing should be rechecked after refitting the cam, before attempting to start the engine''

So, it looks like Ken was correct first time !

Chris.
'My cat can beat up your cat!'
Wavy
Posts: 76
Joined: Mon Jan 01, 2001 12:00 am
Location: GERMANY

Non starting G2 - New owner seeks help.

Post by Wavy »

It may be a coincidence but have you cleaned the point contacts thoroughly?
Branston
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Location: STAFFORDSHIRE UK

Non starting G2 - New owner seeks help.

Post by Branston »

Assuming ignition side is OK, have you checked the carb jets? maybe a foreign body has blocked one of them, (usually the pilot jet). Also its worth draining the carb carefully into a cup and checking for water. Sometimes a small globule of water will be enough to block the jets.(But if you find any water in there you will need to drain the tank and dry it out.)
Good luck
RJG
mn757
Posts: 30
Joined: Sun Mar 22, 2009 10:24 am
Location: WEST MIDLANDS UK

Non starting G2 - New owner seeks help.

Post by mn757 »

Thanks for the suggestions. I'm have ordered a workshop manual and also a new set of points, plug, coil, condenser.

I suspect it's a timing issue, or fueling issue. The plug is getting very wet with fuel so I wonder if its too rich for some reason. Had the float chamber apart and the fuel looks ok.

What I havent worked out yet (in the absence of the manual) is how to set the timing. I can see that the base plate is adjustable on the screws at the side, but the handbook mentions you have to insert a screwdriver into the 5/16th hole to seperate the bob weights.

It also says you need to remove the 'assembly' using a separate tool/bolt - but I cant see why this is needed. I'll have a good read of the book when it arrives and hopefully that will reveal all.

many thanks

Martin.

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davehutch
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Location: LEICESTERSHIRE UK

Non starting G2 - New owner seeks help.

Post by davehutch »

Hi mn757,
I also have a 1960 g2, You need to set the timing 1/4 in B.T.D.C Put a wire through the spark plug hole then turn the engine to find T.D.C., Then make a mark on the wire then take it out make a mark 1/4 in above that mark. Put it back in and turn the engine backwards untill 1/4 in mark. If you put a small screwdriver through the hole in the bottom right of the base plate and open the 2 bob weights the poins should just open. If they don't move the back plate untill they do . Hope this is of help cheers Dave
----Only a biker knows why a dog sticks his head out of a car window.
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