Friday, May 6, 2011

The big problem with dual suspension bikes

There's a big secret going on. As the years go by and I learn more about the intricate workings of the masterpiece that is the bicycle, something bothers me more and more.
Don't get me wrong, I have been riding dual suspension bikes for over 9 years and I loooooove them so very much. I have owned many different bikes and ridden many more. I stand firm on my belief that life is too short to ride a hardtail. Every time I head out on my dually it puts a smile on my face.
Each year there is a flurry of activity as companies release their latest models accompanied by unverifiable performance claims. Still there has been one huge nagging problem that for some reason seems to be ignored. I really have no idea why it has not been addressed by bike companies so I'm just going to complain about it for a little bit.

A failed cartridge bearing pulled from the X-Ben after about 10 months of use.
Bike companies insist on using cartridge bearings for the pivot points on their dual suspension frames. Boy do these things like to fail in a hurry. Imagine being in the bike store drooling over new bikes. Sure you expect that in the course of a year or two you're going to have to replace the tires, drivetrain, brake pads........no big deal, we're all aware of this. But what about rear suspension bearings? Look at that 3, 4, 5, 10++ thousand dollar dual suspension bike. No matter the price or engineering genius, each will experience bearing failure.
As far as I can tell the problem is that these bearings are being used in such a way that they were never designed to be used. Cartridge bearings contained in the rear suspension components move only a fraction of a revolution as the suspension is compressed. The ball bearings don't get the opportunity to rotate through the races as pressure and wear get focused onto one very small part of the bearing unit. Obviously in a perfect world a bearing is designed to equally distribute load onto each ball. They are an engineering masterpiece. However we live in the real world, the fact is that cartridge bearings will wear inconsistently.
All of a sudden your formula one designed super efficient trail warrior has been reduced to a squeaking, clunking mess.
How do you deal with replacing the half dozen or more cartridge bearings when they fail? How will you know when they've failed?

The one saving grace is that the majority of reputable frame builders have moved away from nylon bushings. They wear even faster and are much harder to replace than bearings because they are bike specific. Cartridge bearings are easy to source, are not proprietary to the frame or company, and not astronomically expensive.
It is disturbing to me the amount of dual suspension bikes being sold every year and how few of them have their bearings replaced. People just aren't aware of what is happening
It's not something you want to think about when you selecting your next bike, but you should.

So what can be done about this? When purchasing a dual suspension bike you should keep in mind that the cartridge bearings that make up the rear suspension linkage should be replaced at a regular interval like many other things. I have found this interval to be about 5000km's which for most is 1-3 years but obviously depends on riding conditions.
How much should it cost? Look to spend between $100-$200 to have this done, which is the cost for parts and labour.
The unfortunate part is that there are not very many shops that have the tools or know-how to do this job properly. Even at Hardwood we're not currently set up for this. I am just hoping to raise awareness of this issue since no one else likes to talk about it.
What is the solution to cartridge bearings? I really have no clue. If you can figure it out then send me an email and I'll split you on the patent for the first maintenance free dual suspension frame.
For now I'll just replace my bearings every fall and enjoy my buttery smooth suspension performance. I am hoping to get the tools to be able to do the service properly and professionally so probably the next $500 I get will be going to buying a good bearing press and puller.
What are your experiences with dual suspension bearings??
Benno

7 comments:

  1. My Anthem x is due for this as well, looking forward to posting in one of your How-to's

    Patrick

    ReplyDelete
  2. I've thought the same thing.
    What about roller bearings instead of the ball bearing in a traditional cartridge. They would distribute the load a little more but still doesn't solve the lack of rotation issue though.

    ReplyDelete
  3. it's like there needs to be some sort of floating outer race or ratcheting bearing retainer system to encourage the bearings to rotate along the races.

    ReplyDelete
  4. Try Enduro Max suspension bearings instead of the junk bearing that Giant put on the bike. They are actually designed for low rotation high load applications.

    ReplyDelete
  5. Pretty sure the OE bearings in Giants (as with most bikes) are Enduro brand bearings. Enduro have the market cornered in crap bearings. There is a reason they are 1/2 the price of SKF or NTN. However a quality bearing won't go far in improving bearing life which is why I stick with Enduro for my bearings.
    I am not at all convinced that cramming more balls in the cartridge and eliminating the ball retainer is a logical way of improving bearing life in suspension frames (which is all the max bearing is). I have not seen improved bearing life in the max vs conventional bearing from Enduro.

    ReplyDelete
  6. I have a Titus X bike and it comes factory equipped with enduromax bearings. I am currently experiencing creak after 1 year of heavy riding. Do you guys think this could be the issue? I have taken every pivot appart, cleaned, lubed and used loc-tight on the bolts. It appears to come from the BB area.

    ReplyDelete
  7. Aww tis the season for creaky bikes. I get a lot of people asking me about creaks this time of year. I mainly attribute it to the dry, hot weather. Must be something about the expanding/contraction of all the different alloys that allows dust and dirt to creep in. A lot of these creaks can be attributed to things like the seat/seatpost, bottom bracket, headset, chainrings, cable housing.....
    It is a bit of a black art being able to track down creaks but removing parts and applying a layer of copper anti seize to threads or out bearing shells (headset) can eliminate a lot of them.
    Creaking from cartridge bearings themselves is somewhat rare since they are such a tight fit in the frame. The only way for them to creak is if they are damaged internally. So the very short term solution would be to blast in some penetrating lube like WD40 or T-9. The drawback to that is that you reach a point of no return once you start spraying that stuff into your linkage bearings. I say that because it liquefies the grease inside so if the bearing wasn't actually damaged you can bet that it will be shortly after spraying in that stuff.
    So in short start with the basics like seat/seatpost, headset, BB, chainring bolts, housing stops. Give them a light coat of copper anti-seize to eliminate some variables. That is usually where the problem lies.

    ReplyDelete