23 November 2011 - 8:22Ask George: Week 4

Yet another exciting installment of Ask George greets you. The questions have been a little slow in coming, but I see no reason to stop posting, even though Dicky has been posting on Wednesdays. So, this next question was one from Team 29 rider Emily Brock:

What should I be doing to keep my fork riding well? Is custom fork tuning just kind of a scam?

Good set of questions. For the most part, forks these days are pretty low maintenance. They aren’t no maintenance, but you really only need to make sure you aren’t doing awful things to them. Back in the olden days, this was not the case. I was an early adopter of suspension, and learned the hard way what to do, or sometimes what not to do. Basically there is a short list of simple things that you should do regularly.

1. Keep it clean. A clean fork is a happy, good working fork. It’s actually pretty easy for dirt to compromise the seals, which if unchecked can deplete the oil bath (if your fork has one), or worse, scour the stanchions.

2. Inspect it often. Look for any signs of damage on the stanchions, check for any excessive oily crud build up on them. If it’s really bad, you have a defective seal, or you didn’t follow step 1.

3. Check for any play between the uppers and lowers. This can be a sign of premature bushing wear. If there is play or knocking and your headset is tight, you need to get this addressed, or find yourself a new fork before too long.

4. Get it tuned up once a year, more if you ride in excessively nasty conditions. This means new oil and O-rings. It’s a good idea to get this done during the off season, when you don’t need your bike. Most good LBSs will have the capability to get this done. Not all shops will have bushing presses, and if your fork needs those replaced, it’s generally best to have it sent back to the manufacturer.

As for the second part of the question, is custom tuning a scam? Well, it is my opinion that it depends.

One way to consider custom tuning is the  ”hop ups” one can do to a fork to make it behave differently/better than stock. An example would be the Enduro Wiper Seal upgrade I like to do to all my Rebas. Besides upgrading the fork’s seals, this also gives me the opportunity to make sure that the oil bath is actually there. These days, the forks are mass produced in China like everything else, and quality is not always job 1 with products that are assembled from lots of little pieces. There is a reason why my forks feel super plush.

The actual “custom tuning” aspect is a bit more complicated, and can be interpreted 2 ways. One is correctly setting the fork up for the individual rider. Making sure the air pressure or spring rate is correct for the rider, and adjusting the compression and rebound settings to their preferences. This is all pretty straight forward, and can be done by either the rider themselves or the LBS.

The other would involve tearing apart the whole damper assembly to achieve a specific performance trait. Here is where I call BS on some claims to custom tuning. Some forks, like Rock Shox, use a modular cartridge for the compression damper. The cartridge must sit in an oil environment for it work properly. Others, like White Brothers, treat the entire leg like a cartridge. On both of these systems, oil height is crucial for proper performance. There are stock damper components specific to each fork, that should provide enough of a range of either compression or rebound to please most folks. If it isn’t working properly or feeling punky, chances are the oil height isn’t right.

Forks like Fox are more complex, and use a series of washers, or shim stack, that are easily accessed when the fork is apart. In the right hands, they can be rearranged to gain a certain performance trait. In some cases there are negative springs, that can be rider weight sensitive. Having the right one for rider weight is also crucial for the fork to operate properly. These forks come from the factory with the 175lb rider in mind… This is where having a fork like that can be “customized”, but in reality it’s just being appropriately set up for a rider’s weight and/or riding style. I myself have found it hard to get an aftermarket Fox to feel awesome right out of the box, the adjustments are far too finicky and in some cases redundant (RLC), all of the OE models (RL) have felt fantastic after the seals have had a chance to break in.

But let’s say, for the sake of argument, that your fork has the right set up and oil height. Maybe you have spent $70-100 at your LBS making sure the oil heights are correct, and spring rates are appropriate. 99% of riders out there -professional athletes included, are more than happy with the stock manufacturer’s adjustment offerings between + and -. If you can’t find a setting you like, you have a very specific set of needs, oryou might be too picky, and should try riding a rigid fork for a while.

The fork on my bike costs more than my first mountain bike, and I expect it to perform as advertised. We should hold the manufacturers to a higher standard when it comes to these forks, but the reality is that they are mass produced things that may or may not be assembled correctly. If you are not happy with your fork, you should get it looked at.