Matchless G3L - Fork Alignment Problems

Information relating to the Matchless G3 or AJS Model 16 350cc Heavyweight
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phenry
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Joined: Mon Jun 04, 2018 7:22 pm
Location: Tamil Nadu INDIA

Matchless G3L - Fork Alignment Problems

Post by phenry »

Hello,

Here is the problem that I have. I made the following washers, as the original ones were damaged beyond repair

1. Plate locating for top plate (Screwed)
2. Plate locating for bottom plate (Plain)

The concern here is that after fixing the new washers to the Top and Bottom cover tubes the alignment of the fork is not very straight.
They are just off limits by less than 2 mm or so but I have made them to the exact specifications.
Though not visible to the naked eye they do have some serious alignment problems.
Has anyone encountered a similar problem? Or is there a technique to check the alignment of forks before the front wheel is fixed.

PHenry
56G80S
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Re: Matchless G3L - Fork Alignment Problems

Post by 56G80S »

Not an expert on this but it might help others who are if you explain in what way they are out of alignment.

My memory may betray me here, but I think that one approach is to fit the wheel and ensure the cap bolts are fully tightened at the top of the fork crown. Loosen the long allen bolts at the bottom of the fork yoke, hold onto the front brake and work the forks pushing the G3L hard against the resistance of the brakes. This can line things up. Then retighten the long allen bolts, critical.

If that doesn't do it then there are other steps but also thers on this Forum with better advice! Mine is based on the 56G80S.

Johnny B
Mick D
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Re: Matchless G3L - Fork Alignment Problems

Post by Mick D »

Hi PHenry

Can you give the part numbers of the components you have made please - it will help with diagnosis.

When you say the alignment is not straight do you mean the forks are twisted, (the top and bottom yokes do not align)? If so try Johnny's fix or just slacken the bottom yoke pinch bolts, tap the yokes into alignment and re-tighten the bolts.

Regards Mick
phenry
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Joined: Mon Jun 04, 2018 7:22 pm
Location: Tamil Nadu INDIA

Re: Matchless G3L - Fork Alignment Problems

Post by phenry »

Hi Thank you so much for the suggestions.
The 2 parts that I made are

1. 40-G12M-FF128 - Plate Locating for, Top Plate (Screwed)
2. 40-G12M-FF127 - Plate Locating for, Bottom Plate (Plain)

The problems that I faced were the fork tubes were not sliding into the yoke smoothly like it should and then wheel doesn't seem to sit in a center line.
I am kind of sure it is the washers but just wanted to ensure that the forks are aligned 100%

PHenry
Mick D
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Location: Aberdeenshire

Re: Matchless G3L - Fork Alignment Problems

Post by Mick D »

Hi

Those two parts are not a tight fit on the stanchion so I can't see them being the problem.

When you pull the forks into the yoke you need to have the pinch bolts slackened off - try aligning the forks as above before getting too worried about your plates.

Regards Mick
Andy51
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Location: BERKS UK

Re: Matchless G3L - Fork Alignment Problems

Post by Andy51 »

Hi, have you checked fork stanchions are straight? I had this problem some years ago when assembling 1954 front forks after rebuilding a basket case. One stanchion was slightly bent, not enough to see. I assembled the forks, loosened axle clamp, held front brake on, and 'bounced' forks up and down. Everything worked smoothly. Tightened up clamps, forks went stiff. Did this several times before the penny dropped. Took stanchions out and took them to an engineer at work who checked them with a 2 foot straightedge, you could then see one stanchion was slightly bent. Straightened it in a press measuring against straightedge until you could not see light between straightedge and stanchion. Reassembled forks and they worked perfectly, and have been doing so for over 12 years. Hope this helps, Andy
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1608
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Re: Matchless G3L - Fork Alignment Problems

Post by 1608 »

If by not lined up do you mean both forks are not parallel with each other. Best way is to slacken the pinch bolts in the lower yoke and place two straight edges ) trammel bars)across the forks to determine when they are lined up. Re-tighten the pinch bolts to little more than hand tight and fit the front wheel. With the wheel in place tighten the wheel spindle nut on left fork and then with front brake applied bounce the forks a couple of times and then tighten right hand spindle clamp. Fully tighten pinch bolts.
phenry
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Joined: Mon Jun 04, 2018 7:22 pm
Location: Tamil Nadu INDIA

Re: Matchless G3L - Fork Alignment Problems

Post by phenry »

Thanks everyone. The forks seem to work good now. There was some oil seepage through the fork leg bolts which I arrested using some Teflon tape.
Many thanks again
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