P11 (Matchless Teledraulic) fork disassembly hint

Separating the fork tube and slider on P11 fork legs has always been a PITA. Clamping the tube and using the slider like a slide hammer to free the old fork seal is not as effective as it is with a Roadholder leg. This is due to the buffer spring between the lower bush and top bush. Age and suffering from GMG has reduced my overall strength to make it even more difficult.
While perusing the technical files on the AMC Owners Club website, I found a solution that makes the job much easier. You need two lower Matchless/P11 steering yokes and a small hydraulic jack. Remove the clamping bolt from one lower yoke and clamp it upside down in your vice. Slide the fork leg with the seal holder removed into this yoke and slide the second yoke (right side up) over the tube. Place the jack between the two yokes, fully extend the tube and tighten the clamp. Pump the jack and the spring will be compressed and pull the seal free. The seal can only extend to the bottom of the lower yoke, but grasping the slider you can pull it down off the seal and bushings easily.
I hope some find this helpful

Hi , I haven't pulled apart my G80 forks yet , I heard they were a pita , and I have a gantry so I thought I might clamp some steel rod under the gantry leg slide fork onto it and then I can pull the tube out . Cheers

Gentle heating top end of sliders should ease separation of the thermoset (bakalite) bush and the slider. Bushes are nearly unaffected by heat, but they do swell, so in 50+ years they become a very tight fit.

- Knut

mdt-son said:

Gentle heating top end of sliders should ease separation of the thermoset (bakalite) bush and the slider. Bushes are nearly unaffected by heat, but they do swell, so in 50+ years they become a very tight fit.

- Knut

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I find it is the seal that 'glues' itself to the lower leg. The upper bush is actually turcite (acetal, Delrin) rather than bakelite (phenolic) and is usually pretty easy to pull out. Too much heat will melt the polymer of the seal, just enough heat will expand the aluminum of the lower leg and release the 'bond' of the seal.

Ron L said:

I find it is the seal that 'glues' itself to the lower leg. The upper bush is actually turcite (acetal, Delrin) rather than bakelite (phenolic) and is usually pretty easy to pull out. Too much heat will melt the polymer of the seal, just enough heat will expand the aluminum of the lower leg and release the 'bond' of the seal.

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I am pretty sure the original bush was made of Bakelite (I believe AMC said so in an advert). Modern replacements may be Delrin, I don't know. Delrin was made commercially available by DuPont from 1960 on. Being a conservative company, it's unlikely AMC ever used Delrin for fork bushes.
A thermoset polymer, Bakelite doesn't melt with heat, it chars at comparatively high temperatures.

- Knut

mdt-son said:

I am pretty sure the original bush was made of Bakelite (I believe AMC said so in an advert). Modern replacements may be Delrin, I don't know. Delrin was made commercially available by DuPont from 1960 on. Being a conservative company, it's unlikely AMC ever used Delrin for fork bushes.
A thermoset polymer, Bakelite doesn't melt with heat, it chars at comparatively high temperatures.

- Knut

Click to expand...

I am well aware of Bakelite phenolic polymer. In my corporate life we made and used phenolic resins. As far as AMC/Norton using the name in advertising, they also claimed the P11 frame was 'ChromMoly' when it is Reynolds 531. ChromMoly is a chrome and molybdenum alloy while 531 was a manganese and molybdenum alloy. Just sayin'.

I have four sets of P11 forks and the top bush in all are black and do look similar to phenolic, but are not brittle like Bakelite. Acetal polymers are often used to provide lubricity but as you infer, it does not have great thermal stability. A fork bush would not necessarily require this. The engineering term 'Turcite" has been used for acetal polymers infused with powdered metal as well as PTFE.

Interestingly, the top bush that AN supplies is a gray material, but I don't know its composition. I also have a set of replacement bushings that if memory serves me correctly came from Walridge and are bronze.

Just, finally got my 49 matchless g80 cone and shuttle front forks apart , they do have the cone bolted into the lower fork leg , can anyone confirm this is the correct 1 ⅛ stanchion ? There are 4 holes under the alloy spacer which is stepped , these forks have absolutely no dampening, you cannot even hear the 9½ fluid Oz of oil in them , previous owner has rebuilt them , but this bike was rebuilt 25+ years ago , never ridden on the road . I was looking at those p11 forks and that ring that is on my forks is very similar ? But the G80 fork diagram on page 23 sort of shows a slightly bigger step where the alloy spacer fits, i have new spares from club spares amc. Any help much appreciated . Cheers here are some pics . Any help much appreciated.