Fork seals and tying down?

[t3mp0r4ry nzr]

with my road bikes I have always tied down the forks till there is very little verticle movement but I have heard mutterings of not doing this with an MXer. So how much do you tie the front down in order to make the bike stable in transport but not stuff the fork seals? or is this a myth?

[Mental Trousers]

Problem with compressing the forks/shock is that you're pressurizing the internals, which can lead to gas dissolving into the fluids and you can blow fork seals.

Ideally you wouldn't compress the forks/shock on either. You can get bike trailers that secure both wheels so they can't move at all and then loosely hold the rest of the bike just so they don't jump around too much. Alternatively, getting an old mattress, leaning it against the side and then lean the bike against that and tie it so that's it pressed into the mattress is the way most racers do it.

[F5 Dave]

Well teh professional way to do it is tie them lightly inside a van. But if you have to use one of those trailer thingys then you can buy spacers to fit between the tyre & front guard & tie down against that. Do a search, think dirtbike.co.nz or whatever have them

Or just make from wood. Need a curve in them so they don't get spat out.

[White trash]

For the record I don't compress the front suspension on my road bike at all either.

[Quicker_with_age]

I have read numerous times that its just a myth that tieing down your front forks causes leaking seals and I would tend to agree, The oil is never under pressure it simply passes through the valves, If the suspenson can handle the abuse a motocross track throws at it I very much doubt that pulling it down while transporting it will harm it, I guess extended periods of being tied down could cause the springs to compress slightly but thats about it.

[ricey]

Just buy some fork relief valves for $29, bleed the Air out of them before you pull them down, because they do build up pressure. If they leak after that they were going to anyway. Like any seal they wear out, especially if you ride on sand a lot.

You could use a spacer and pull the bike down onto that, but if that falls out for any reason then your rooted!

[Ocean1]

I have read numerous times that its just a myth that tieing down your front forks causes leaking seals and I would tend to agree, The oil is never under pressure it simply passes through the valves, If the suspenson can handle the abuse a motocross track throws at it I very much doubt that pulling it down while transporting it will harm it, I guess extended periods of being tied down could cause the springs to compress slightly but thats about it.

That'd be my take on it, at least with any normal set-up.

And it'd take a fair while under load to affect springs.

[scott411]

Im with quicker on this,

forks are not under pressure, the only thing that could maybe argue is the tension on the springs, but since they are already preloaded its not really an issue,

[Dino]

Im with quicker on this,

,

+1 I would rather make sure my bike is nice and secure on a bouncing trailer than worrying about a myth.

[barty5]

i have been towin bike round for the 20 years never blown a seal yet from tieing it down with or with out a spacer in the front wheel most of the time not. Would rather tie it down nice and safe than have it fall off (which has happened due to tie down failure)cause of stressing bout fork seals.

[Pierce]

I've got an 'I' bar that sits between the top of the tyre and bottom of the front fender bolts. Basically means you can pull your ties tight without using the shock. I think the bikes can handle it but for long trips it'd defo help with longivity of shocks.

[CookMySock]

[....]which can lead to gas dissolving into the fluids..

I am no BSC but I think this description is largely infeasible.

I think racers take all and any care, to the absurd, because whether it pays off or not is not so much the point, as in it MIGHT pay off - So they just do it - on the chance that it might just be the winning trick of the day. The same argument applies for hifi speaker wiring et al - it is nearly impossible to pick the difference on a single passive component, but the combination of the ultra pedantic approach does give a measurable result. Or maybe it just makes us feel better - an easily measurable result.

DB

[CRF119]

Ive been tying bikes down for along time like that and has never caused a problem i see hundreds of bikes tied down with no spacer. The suspension is more compressed when you are sitting on it any way so over a 3 hour ride the forks have done far more work then if they were tied down over a 3 hour drive. I only pull my bike down about 4" which is more then enough. I used to have a spacer but was more hassel then it was worth.

I do see some people pull the forks down way past half the stroke. That could be what is stuffing forks. But i have never had a problem.

[xwhatsit]

Now, I'm a silly fellow with no idea about suspension, and my only experience with forks is the ancient technology of damper rod units. However, unless the oil is well over-full, what pressure are you putting on the fork seals? Fully compressed the oil shouldn't be causing hydro-lock, should it? The damper unit should mechanically bottom out first -- on my forks, there's a wee extra spring on the bottom to stop a painful *smack* of parts hitting together, but certainly the oil shouldn't be hydro-locking.

[B0000M]

this would be a good one for danger....