PO - front brake stay - wrong type?

Information relating to the Matchless G80 or AJS Model 18 500cc Heavyweight.
StephenG80
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Re: PO - front brake stay - wrong type?

Post by StephenG80 »

Ok - thanks for all the discussion and photos- that gave me confidence that it was not a case of the wrong stay having been fitted which was my main question. Having established that I took the existing stay of off and did a little fettling on the rear bolt/stud hole in the stay on the top side - just a mm plus was enough for it to swing forward and all line up perfectly :beer: . Something in the bikes history must have put this out of kilter, either repair work on the stay or new threads in the fork lower. Who knows. Anyhow as with all these things it also brought more insight into my bike - I now know I have later fork bottoms! : :geek: :ugeek:

One remaining Q: on some pictures it shows the brake lever arm at the rear coming from behind the fork lower as below
Capture.JPG


- someone suggested this is how mine should be set up on another group, but the geometry would not line up at all - so presumably this is a different design of backing plate on a later model? - be great is someone can confirm this.
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Mick D
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Re: PO - front brake stay - wrong type?

Post by Mick D »

Hi

Yes, that's a later modification, not sure when it was introduced but is as per my 1961 G3.

Regards Mick
Reynard24
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Re: PO - front brake stay - wrong type?

Post by Reynard24 »

Your photo is a little unclear due to the angle but it looks like you have a 1955 front wheel - the radial fins protrude slightly beyond the drum rather than being flush with it. If this the case then you have the correct curved brake lever which should be at the bottom. 1956 on bikes have a curved lever higher up behind the fork slider.
StephenG80
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Re: PO - front brake stay - wrong type?

Post by StephenG80 »

Mick D wrote:Hi

From the parts lists it looks like you have a bitza hub / brake plate - the 54 shows the brake lever pointing to the rear and hence used a different torque stay, (with the cable facility at the rear), pt no 018655. Edited to add - looks like the parts manual illustration is misleading :roll: .

Your brake lever looks identical to my 60 one, formed to fit inside the slider above the wheel spindle.

I'd study the parts lists in the archive to try and determine what you've got.

Regards Mick
Yes the parts list threw me - on page 53 they show the stay flipped -which sent me down a whole different route!
56G80S
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Re: PO - front brake stay - wrong type?

Post by 56G80S »

Stephen

Reynard wrote "1956 on bikes have a curved lever higher up behind the fork slider."

And is spot on, that's how mine is.

Johnny B
StephenG80
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Re: PO - front brake stay - wrong type?

Post by StephenG80 »

56G80S wrote:Stephen

Reynard wrote "1956 on bikes have a curved lever higher up behind the fork slider."

And is spot on, that's how mine is.

Johnny B
:beer: :D
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clive
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Re: PO - front brake stay - wrong type?

Post by clive »

Couple of points. The first and most important is that at the beginning of the thread you said you assumed the BOLT that held the brake stay at point 3 in your photo fell out. The issue here is I was always thinking that this should be a stud with plain shank where the brake stay impacts on it. It should not be a bolt. Each time a bolt is removed it will fractionally weaken the fit in the ally slider making it more vulnerable to fall out over time. A stud can be locktited in place and you can still take the brake stay off if required.
I struggled to find the part number but eventually tracked it down under the mudguard section in the parts list. Right slider has bolt 010795 to secure the mudguard (same as the stay bolts). Left slider has stud 010624 which it notes is 1 1/32 long by 5/16and has 22tpi at the slider end and standard 26 tpi for the nut.
Second point. Although you are a paid up club member your profile on the forum is showing you as a guest. This means you will not be able to access all the site and will only see the members adverts 3 weeks after they have appeared in the mag. Email Eamonn at wembmaster@jampot.com to get it sorted.
clive
if it ain't broke don't fix
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robcurrie
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Re: PO - front brake stay - wrong type?

Post by robcurrie »

I agree with Clive about rather using studs, but the length must be carefully calculated so that you don't snooker yourself when it comes to removing the wheel (without having to deflate the tyre).

Rob C
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1608
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Re: PO - front brake stay - wrong type?

Post by 1608 »

Just an after-thought. Your stay may have been fitted to the O/S some time in the past ( which is obviously wrong but does happen ). This means that when the brakes are applied the stay is under compression rather than tension which may have compressed the stay just enough to cause your problem.
StephenG80
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Re: PO - front brake stay - wrong type?

Post by StephenG80 »

1608, Robcurrie, Clive - thanks for all those points :beer:

- Clive studs are on the list of jobs. :ugeek: :beer:
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