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potto

Cota 349 fork seals ?

6 posts in this topic

Bought new for seals and just wondering about there placement,it would appear they just sit on top of each other with the lips upwards....correct ?

Besides cleaning the sliders and tubes anything else required before reassembly ?.

The spring spacers that In Motion sell are they to compensate for weakened spring or something else?

Thanks.

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The big lips point downwards. Small lips (if any) point upwards. The side with the writing faces up. If you have two seals per leg, yes both seals go the same way up.

What spring spacers are you asking about?

Those forks sometimes suffer from a plastic part at the bottom of the damper rod becoming a tight fit in the hole they go into as the forks bottom. You can test for this by working the sliders. If they stick at the end of the travel, it is a good idea to machine the part back to size or make aluminium replacements while the forks are apart. They are white/translucent plastic tapered cylinder shape and fit between the bottom end of the damper rod and the slider. They are called anti-bottoming cones

Edited by feetupfun
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Point of interest didn't the Montesa Honda 349 variant revert to single seal arrangements

I seem to remember mine quickly leaked the old double seal arrangement being much more reliable

one to remember Honda if it aint broke don't fix it      Viva Montesa :o 

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The spacers I refered to that In Motion sell are made of alloy and fit on the end of the springs as far as I know.

I bought 4 seals as that is correct for my 51M 349 size is 35x47x7 ,hope my info wasn't wrong...parts book shows 2 seals/slider.

Thanks again.

 

 

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Fork spring preload spacers are used to tune the preload to give you the right "sag". You adjust the sag with the bike assembled by taking the caps off. If someone rode it successfully before you got it there is a good chance that the sag will be in the ballpark already.

With fork seals in your 349, you can use two skinny ones or one wide one. You are only limited by the depth of the hole below the retaining clip. Yes, In Motion sell the skinny ones and using two skinny ones was common practice when the bikes were new, and is still commonly done and it usually works well. Some people seeking to reduce the friction fit only one (wider, double-lipped) seal and some people reduce the tension on the tiny springs that hold the lips against the tubes. It's a free world. What you are doing has a good probability of success. SKF have started making fork seals from some modern fancy low friction material and they are available in your size and are expensive. I've yet to try the SKF seals and the Spanish forks I put together last week (Bultaco M85) have the In Motion seals in them. The Spanish forks I did before that I fitted a single 10.5mm wide seal (Bultaco M49) and they worked fine too.

One problem cropping up with our old bikes is that the sliders can develop enough wear to cause the tube to move about too much (radially) in the slider for the seal to work properly. Modern forks have replaceable bushings in the sliders but the old bikes don't have this. If the play is causing problems, they can be machined out to take a sleeve or maybe replaced with less-worn second hand sliders.

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1 hour ago, feetupfun said:

One problem cropping up with our old bikes is that the sliders can develop enough wear to cause the tube to move about too much (radially) in the slider for the seal to work properly. Modern forks have replaceable bushings in the sliders but the old bikes don't have this. If the play is causing problems, they can be machined out to take a sleeve or maybe replaced with less-worn second hand sliders.

The sliders are easy enough to machine if you have access to a reasonable lathe - the outside where the gaiters go is concentric with the bore, so easy to set up - then press in a suitable piece of brass tubing and ream/machine to size. Any competent machine shop should be able to do it.

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