The Golden Wrench

A blog about bicycle repair and maintenance by the mechanics at Freewheel Bike.

Monday, January 16, 2012

Old forks and old bikes, when is when and riding in snow...

This is what a terminal illness looks like for a suspension fork.
  A lot of forks come through the door here and as far as I know Shockspital repairs more older forks than anyone. The hard question is always "Is it worth saving?".
  For as long as Shockspital has been around I have maintained that it doesn't cost anything to find out if it is saveable so when a fork comes in, especially an older one we look to answer this question first.
  With older forks we do try and give special consideration to special situations. Exceptional bikes that were born to early to purchase replacement forks for now are a common problem.
  Bontrager and Klien are two big exceptions we have to work with. A 1997 Judy is not a fork worth the $125 to $200 it takes to rebuild it but if you have an old Racelite or Attitude it might be worth to you. (I would recommend a thorough and honest look at the bike before you decide to make the investment). So we maintain parts and tools to work on this older stuff.
  But do not count on the rebuild service to save your bacon if your stanchions look like this. Old or new forks are vulnerable to this kind of wear if you don't maintain them. Whether its a new Fox or a Halson Inversion you have to keep the stanchions clean. This is a bigger deal than ever during winter riding. Here are a couple of things to keep in mind.
1. Water, aluminum, steel and magnesium are just four things that can be found in your fork most of the time, but winter riding can add salt! Then you have all the ingredients to make a low voltage batter that will grow corrosion inside your fork quicker than grass through a goose.
2. Dirt and mud and the grit they contain are easily wiped off during most riding. Your fork is prepaired to handle these elements . But when you add snow and ice this fine particulate matter is not as easily wiped away. The dirt that is the finest is the most damaging and snow and ice can keep this packed on your stanchions for an entire ride.
3. Oil viscosity changes in the cold weather. Thus the now colder and thicker oil applies more resistance to everything inside the fork including its self. The pistons in your damper are meeting more resistance than normal because of the higher viscosity oil; this will change your damping and in the case of some older Manitous and Rockshox it could actually snap the piston off your damper shaft. (most oils don't have enough viscosity change to do this anymore).
4. Lubricating oils don't move as freely in your fork so your bushing stay dryer and wear faster as well as increasing wear on your stanchions.
5. And lastly, as everything in your fork gets cooler; all the rubber gets harder. Worse case scenario is your Pace fork might collapse totally as the seal gets to rigid to seal air or your Fox might puke its guts out of the upper seal and all over your disc brake (yuck!).
  This doesn't mean don't ride suspension in the winter, this stuff is made to be broken; its the price of admission. We aren't knitting scarves here. BUT you will have to take better care during the season.
  • Keep your mountain bike off the streets (that's where the salt is). Salt is hard to beat and contamination is minute and invisible till things go south.
  • Wipe your fork with a soft rag when you are done (before and after your bike thaws).
  • Fork oil is a mess but an ideal lubricant for your wiper seals before and after a ride (a little triflow works well also). This will keep your seals from stiffening up and sticking to the stanchions while riding. Just wetting the seal with a gooey rag is enough.
  • Replenish your air pressures often. Just like in a car tire, temperature changes will affect your pressure. (coils hand the cold WAY better).
  • Some forks, older Manitous and cheaper Rockshox  Dukes and Psylos (non lock out XC models) will live longer staying home below freezing.
  • Your Bontrager Racelite and its 96 Judy SL should not be let out in anything less than a perfect spring day.
Hopes this helps,
B Rose