Is this Dangerous?

[Spibblo]

My Bro wants his Manitou SX forks to be stiffer / have less travel for a forthcoming road trip.
They are the 1999 model with TPC in the right leg and a coil / elastomer in the left.
They had a really springy feeling and no matter what adjustments I made it didn't get much better.

Today I took the cap off the left leg and filled it with fork oil. Now the forks compress about 10-15mm and then they're pretty hard afterwoods.

Before I try this out on the road or worse, let my Bro take it home to try it- is this safe? will the pressure be too much and cause the fork to implode?

I know F**k all about sus forksi BTW

 

[xam1]

Re:

Not very wise thing to do overfilling fork with oil. Yes, it stiffens the fork, howver those top caps are plastic and can blow up from there or other damage can occur because of the excessive pressure caused. Even the service manual has warning about it. The recommended oil level is 104mm or at least between 83-114mm from the top. Don't be stupid, do it right or get some rigid fork for your brother.

 

[Spibblo]

Re: Re:

Not very wise thing to do overfilling fork with oil. Yes, it stiffens the fork, howver those top caps are plastic and can blow up from there or other damage can occur because of the excessive pressure caused. Even the service manual has warning about it. The recommended oil level is 104mm or at least between 83-114mm from the top. Don't be stupid, do it right or get some rigid fork for your brother.

I'd forgotten about posting this, yeah it does sound stupid. Though it was a great drunken afternoon filling the forks up with oil, rest assured no actual people were or will be harmed as a result. I'll ditch the forks.

 

[02gf74]

I was thinking similar the other day. Fitting a spring to air fork. (Fork has tendency to leak)

Like "^^^^ i did consider the plasti c cap being pushed off but surely the force of the compressed air will be the same as that of the spring ( or in this case oil), hence in my mind itll be fine. Discuss.

 

[cce]

go on for sale section. buy rigid fork for 25 quid.

 

[Raging_Bulls]

Re:

regarding OP : Too much oil will drastically increase pressures within the fork whenever it compresses. The question is not IF, but WHEN it will blow the top cap and all that oil into someone's face.

@02gf74 : If your air fork is leaking, it's almost always a matter of re-greasing or replacing the rubber seals inside the spring.

Look for a manual or step-by-step guide online, order a new seal kit (eBay is the most likely place to find them) and overhaul it.
Takes an afternoon at most if you're inexperienced, but it'll be a much better solution than messing around with springs until you find one that has the right stiffness.