AJS Model 8 seized teledraulic forks

Information relating to the Matchless G5 or AJS Model 8 350cc Lightweight
Steve S
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AJS Model 8 seized teledraulic forks

Post by Steve S »

Hi, this is my first post having just bought a 1960 Model 8 where the forks appear to be seized. Reading the past discussions on this issue I guess it might be the plastic bushes that are responsible. I've many years' of experience of tearing down bikes and even re-assembling them, but would really appreciate some advice on how to go about doing this. If I think it's beyond my skills, is there a firm in the South East that is recommended?
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clive
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Re: AJS Model 8 seized teledraulic forks

Post by clive »

Hi Steve welcome, quite a few of the club members have been on a rally this weekend. Not sure about the lightweight forks but I think they fitted the earlier version of the heavyweight forks to some models. May be wrong but if so they are relatively easy to work on. You will need a fork puller to get the stanchions in and out of the headstock, and will need to heat the fork slider with a blow lamp ( moving it around all the time of course) to pull the plastic bush out. I heat it and then trap the slider in a workmate, and pull sharply upwards, taking care to clean the entire shed from the oil sprayed around afterwards.
clive
if it ain't broke don't fix
Mick D
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Re: AJS Model 8 seized teledraulic forks

Post by Mick D »

Hi

If the forks have stopped compressing / extending it's probable that the stanchions have gone rusty and are now jammed in the plastic upper bushes or they are bent following a bump, so the normal method of removing the bushes described by Clive will not work.
If this is the case, remove the front wheel and remove the forks from the steering head, the springs and washers / sleeves will lift off now and you will see the condition of the stanchions once you have done this.
Unscrew the chrome sleeves from the tops of the sliders.
Empty out the fork oil via the drain plugs at the bottom of the sliders.
Place a spindle sized bar, (or large bolt), where the wheel spindle would fit and nip up the clamp.
Grip the stanchion in a vice, (protect the finish if it's salvageable with vise grips), and tap the bar / bolt to extend the fork leg and withdraw the plastic bush and oil seal.

I suggest you download the relevant manual and also the 57 - 64 Workshop manual from Christian's archive.

http://archives.jampot.dk/

Regards Mick
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BultacoBen
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Re: AJS Model 8 seized teledraulic forks

Post by BultacoBen »

Hi Steve,

Welcome! I recently rebuilt the 1 1/8" teledraulics on my lightweight 250 CSR. The rebuild itself was relatively easy but getting the forks out the yokes proved to be the biggest trouble.

Documented here: http://www.jampot.com/forum/viewtopic.p ... 3&start=10 and eventually resolved with liberal application of heat.

They forks themselves were seized with what appeared to be very corroded stanchions binding to the bushes. Although pretty bad cosmetically they cleaned up reasonably with wire brushing and then wet-and-dry. Still a bit pitted but don't appear to leak oil past the seals so I'm happy. Some would say if corroded then replace, but since the stanchions are pretty pricey I'd give the stanchions a go with a clean up before resorting to new ones if they leak oil badly.

The 'puller' as described by Ken de Groome in his excellent article on rebuilding teledraulics is vital for getting the forks back into the yokes. Links here: http://www.jampot.com/forum/viewtopic.php?f=8&t=7260 The puller can be made up from an old top bolt, but is I think also available from the spares department.
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Steve S
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Re: AJS Model 8 seized teledraulic forks

Post by Steve S »

Thank you all very much for your invaluable advice and reference to previous posts and resources. This has given me the confidence and optimism to tackle the repair myself - I will report back late October when I will have a chance to get down to it. If there are any other folk out there who have been through this I'd be delighted to hear further from you all!
Steve S
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Re: AJS Model 8 seized teledraulic forks

Post by Steve S »

Hi, removed the front wheel and one fork leg immediately freed itself and the brake side one remained seized. Freed it with a little gentle hammering on a tube clamped to the bracket as recommended elsewhere, but the slider remains very stiff and would not operate as a proper slider if I reassembled at this stage. Could someone recommend a way to free it up without substantial disassembly please?

Steve S
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Janet
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Re: AJS Model 8 seized teledraulic forks

Post by Janet »

Mick D wrote:Unscrew the chrome sleeves from the tops of the sliders.
That bit made me laugh as I remembered............
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Mick D
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Re: AJS Model 8 seized teledraulic forks

Post by Mick D »

Hi

If one slider freed itself when the wheel was removed I would consider this to be indicative of the front end having had a bump in the past. I'd check the alignment of the sliders, can you offer up the wheel spindle and seat it in both sliders without any force? If not you probably have a bent stanchion(s).

I would remove the fork legs from the yokes and see what things look like from there. Unfortunately this will mean buying / borrowing / making tooling to re-assemble the fork legs into the yokes.

Regards Mick
Mick D
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Re: AJS Model 8 seized teledraulic forks

Post by Mick D »

Janet wrote:Mick D wrote:Unscrew the chrome sleeves from the tops of the sliders.That bit made me laugh as I remembered............
Hi

Yeah I know - just 'unscrew the trim' - three little words :roll:

One came off by hand after applying a little heat

The other: :evil:
Slider Trim.png
Required a bit more persuasion - in the form of a cutting disc, pliers and 'C' spanner.

Or have I missed the point?

Regards Mick
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Janet
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Re: AJS Model 8 seized teledraulic forks

Post by Janet »

Mick D wrote:Required a bit more persuasion - in the form of a cutting disc, pliers and 'C' spanner.

Or have I missed the point?
No, you hit the bullseye.

Apologies to those who have read this before.
"Unscrewing the fork extension was a completely different seafood cooker. With hands installed in rubber gloves for added grip, I grasped the part and tried turning. Bearing in mind I ride a Honda 400/4 which must have one of the heaviest clutches and throttle return ever fitted to a bike, my hands are not exactly weak. Result, nothing! I tried the rubber strap tool for turning, but abandoned that because it just slid round without any effect. So then I got out the gas torch to apply some heat. It was at this point, as I set fire to my thumb with the lighter, I began to feel that my anticipation of the difficulty of the job was probably closer to truth than had been indicated by others. Having extinguished myself, I gave the fork slide a liberal amount of heat, then attempted to turn the extension. Result, nothing!! Thinks. The extension screws into the slider? Yes, so I am correct in heating the slider to try to get it to expand away from the the extension inside. Well' it didn't work anyway.
At this point I rang Gary Corcoran, a terribly grand chap in Leeds who had offered to lend me some tools if I needed them. Did he have any suggestions for alternative methods? Only that I could try some stillsons but they normally damage the part they're gripping. However he had a spare, albeit in poor condition, ie with chrome missing, that I could have if I totally mangled mine. That made me feel better as I knew there was a replacement available with the added advantage that it would be totally in keeping with the patina of my machine. I decided that the 16” stillies would be big enough, wrapped the tube with a cloth and applied some pressure. Nothing!!! Ah, to hell with it, I gave it a bit more force and felt a moment of Triumph (odd because it is a Matchless) as there was some movement. Also, if you didn't know better, in a poor light, and without your reading specs, you wouldn't be able to tell what I'd used.
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