Air build up in Forks

[Mark DrinkwalterMember]

Mick, that is funky shit. I take note of leaky fork seals here for service and its about 50 / 50 as to which one leaks. Maybe you brake too much…

Hatto the hijacker – 3-4 days right now, quicker if you pay in scotch.

ER

[Craig HattonMember]

Evil Rudy wrote:

Mick, that is funky shit. I take note of leaky fork seals here for service and its about 50 / 50 as to which one leaks. Maybe you brake too much…

Hatto the hijacker – 3-4 days right now, quicker if you pay in scotch.

ER

Thanks Rudy, what freight company do you usually use, I will send tomorrow

hatto

[Jeffrey SmithMember]

Could it be less about the braking pressure from one side to the other and more about the brake disc channeling the muck straight up the fork leg perhaps?

[Mick DMember]

Jeffro wrote:

Could it be less about the braking pressure from one side to the other and more about the brake disc channeling the muck straight up the fork leg perhaps?

Jeffro, you are a thinker aren’t you… :laugh:

[Mark BuntingMember]

Evil One

Why don’t you like the air bleeders thingies ???

Kram

[GregMember]

kram140 wrote:

Evil One

Why don’t you like the air bleeders thingies ???

Kram

They suck air into the fork more often than not

TB

[Dwayne OMember]

I try to remember to open the Bleed Screws after each full days ride and store the bike up on a liftstand when not riding (if it is sitting for mare than two days anyway)

Think it helps with reducung pressure & wear on the seals etc, could be wrong but it can`t hurt I reckon :whistle:

[AlexMember]

Yep bleeders leak. I have had a few sets of forks in my day and have never run bleeders. All my forks have built up air pressure. Im not saying the brake side seals wear more.

[Scott HanleyMember]

Just a thought but a bit of air pressure should keep the shit out. I did my time in hydraulics and we used to make rams with a 10000psi fluid pressure with chromed shafts and single lip seals no different than a fork seal. So in conclusion the seal should have no problem with a little air pressure which would be no more than 20-30 psi (guess not measured). I would look more at shaft damage incorrect seal placement shit forced under the seal.

Cheers
Scotto

[James RookyardMember]

Agree with above ^^ statement. Air pressure build up would effect suspension action and really not cause seals to start leaking. They don’t actually “blow”. They weep because of crap caught under them.
Why can’t we go back to the old XR style valve style bleeders? They were light years ahead of the agricultural screw idea. Another backward step from motocross bikes, that goes hand in hand with those poxy bolt and nut chain adjusters. No tools required for a valve stem setup. just unscrew the cap and push the valve in. They didn’t leak either.

[dennis da menaceMember]

i was thinking cavitation maybe, from the oil in one leg being crap, since its a new bike.

just a long shot.

i was reading something about it the other day, but my memory is temporarily unavailable due to a scotch buildup :laugh: :laugh:

[AlexMember]

This is a 2011 thread lads. After all was said and done I was right. Mick even proved it. Brake side leaks more often due to that side binding the fork more. It’s basic physics people! The pressure on the seal introduces more air into the fork on that side so it builds up more.

[James RookyardMember]

Basic physics would say that the forks are bolted together and so the load from the brake has to be shared equally between the two fork legs. They don’t work independently of each other. Even if the fork was twisted under load from the brake, the other fork would be twisted equally.
I tend to think the disc throwing crap up the fork leg is the most likely cause as stated earlier.
Air compresses so the tiny amount in the fork leg would have little effect on the seal. Cavitaion of the oil and air mixed together would certainly affect the oils performance though. Thats why they went to nitrogen in shocks in the first place.

[AlexMember]

I don’t agree with most of that Jimmy.
There is gyro force there. Brak:ng will want to pull the wheel off its axis when restricted by one end of the axle. Steel and bolts flex. Forks do flex.

[Steve WyethMember]

Sorry Axel but I agree with Jimmy. Basics physics as you mention is responsible for ensuring any load on the front wheel or the forks is transmitted evenly through both forks and the triple clamps.

Since they are fixed at both the top and the bottom I see there can be no other outcome. How do you think MTB and the new separate function forks work with comp in one leg and reb in the other?

Dirt from the brake doesn’t seem overly credible to me either since my seal started to leak having not seen mud of any kind for months, however, at least it is possible unlike the other theory.

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