Mk3 Commando fork seized

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Hi All, this is my first post.
I recently removed the front wheel on my Mk3 to replace the tube.
Due to work commitments, a few days passed before I got around to replacing the wheel. I noticed that the right fork leg had totally retracted and is siezed in that position. Does anyone have any idea of the cause and how to fix it please. Any help would be greatly appreciated.
Thanks, Pete.
 

Esmerela

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Hi All, this is my first post.
I recently removed the front wheel on my Mk3 to replace the tube.
Due to work commitments, a few days passed before I got around to replacing the wheel. I noticed that the right fork leg had totally retracted and is siezed in that position. Does anyone have any idea of the cause and how to fix it please. Any help would be greatly appreciated.
Thanks, Pete.
The water in the pool must be bloody cold;)

I would try removing the fork oil drain screw let some air in there, then as your head man said check your fork oil.
 
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I am in Brissy only to happy to help you out if you need a hand, just PM me.

Ashley
 
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I am in Brissy only to happy to help you out if you need a hand, just PM me.

Ashley
Thanks Ashman,
I really appreciate the offer.
I removed the oil drain screw as suggested by Esmerela last night. This morning it is still frozen in the retracted position. I was reading up on how to fill the oil in the fork last night. I’m hoping that if I remove the fill bolts I might be able to get the fork tube to slide down into position.
Cheers, Pete.
 

L.A.B.

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I removed the oil drain screw as suggested by Esmerela last night. This morning it is still frozen in the retracted position. I was reading up on how to fill the oil in the fork last night. I’m hoping that if I remove the fill bolts I might be able to get the fork tube to slide down into position.
I don't understand how the RH fork "tube" (do you mean the slider?) could have "retracted" as with no weight on the fork (assuming the front end was left propped up to remove the wheel?) then the fork spring should hold it at the fully extended position. Assuming you didn't remove the mudguard bridge when you removed the wheel then I also don't understand how only the RH "tube" has "retracted"?
 

gortnipper

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I wondered that too. My guess is the other one extended... and there is some stiction holding the "retracted" one?
 

L.A.B.

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I wondered that too. My guess is the other one extended...
Yes, I was thinking the LH slider might have 'dropped' which could happen if the LH damper rod or tube cap has unscrewed but not unless the mudguard bridge has been removed.

and there is some stiction holding the "retracted" one?
Or the fork spring?
 
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I'm still attempting to form a mental picture of this happening, and I only had my forks apart last month. Now have to look at drawings because this is disturbing.
 
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I don't understand how the RH fork "tube" (do you mean the slider?) could have "retracted" as with no weight on the fork (assuming the front end was left propped up to remove the wheel?) then the fork spring should hold it at the fully extended position. Assuming you didn't remove the mudguard bridge when you removed the wheel then I also don't understand how only the RH "tube" has "retracted"?
Hi L.A.B., thanks for your interest. I assumed the right slider had retracted but I could be wrong. When I first noticed the problem, the mudguard was still bolted on and was twisted out of shape.
The distance from the bottom of the lower fork yoke to the top of the gaiter is 101mm on the Right hand side and 184 mm on the left.
I can move the left slider up and down by hand about 15 mm and it rotates. I can’t move the right side at all.
Thanks again.
Pete.
 
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I'm still attempting to form a mental picture of this happening, and I only had my forks apart last month. Now have to look at drawings because this is disturbing.
Hi, thanks for your interest.
I just tried to take a photo and post it but I failed. The right hand side definitely looks like it is fully retracted. There doesn’t appear to be any wear above the gaiter.
Cheers,
Pete.
 

Esmerela

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Hi Pete


Have you tried giving the RH slider a whack to get it to drop ? If you lift the gaiter use a wooden drift on top of the fork seal retainer and give it a smack down it may release, Perhaps you have a bent stanchion causing it to jam. Though the mystery of how it retracted may never be solved!

Be careful with the chrome and keep your thumb out of the way;)
 
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Hi Pete


Have you tried giving the RH slider a whack to get it to drop ? If you lift the gaiter use a wooden drift on top of the fork seal retainer and give it a smack down it may release, Perhaps you have a bent stanchion causing it to jam. Though the mystery of how it retracted may never be solved!

Be careful with the chrome and keep your thumb out of the way;)
Thanks Esmerela,
I’ll give it a go.
 

L.A.B.

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I assumed the right slider had retracted but I could be wrong. When I first noticed the problem, the mudguard was still bolted on and was twisted out of shape.
The distance from the bottom of the lower fork yoke to the top of the gaiter is 101mm on the Right hand side and 184 mm on the left.
"184mm on the left" sounds normal so I can't understand how the RH leg (slider?) could have apparently retracted all by itself after you removed the wheel.
 
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Did oil come out when the drain plug was removed from bottom of slider? If not then probably seized bushing.....Just pondering as no mention after removal..

Tubes(stanchions)are thin, but pretty stout. Launched mine through a 6' fence in my wilder younger years doing....well got it slowed down to perhaps 25mph, & tore up everything except frontend. It was chain link so it had some give to it, but it hurt both pride and body equally. Damned front MC shot fluid all over right hand helping nothing with slowing. I'm saying one has to hit something quite big with no give or run dry in my limited experience, or a combination. They are kind of tough & well made.
 
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