Sunday, October 14, 2007

Bushings are they all the same?

So I was in visiting On Top Bike shop and the wrenches up there were having a look at the Legend. I informed them that the Legend was pegged to have all bushings rather then bearings at every pivot.
Now these guys have seen just about everything, and so their opinions really count because its knowledge from experience. They had some reservations considering they felt bushings wearout faster then bearings.
I have also spoken to a few other engineers and we do agree it is possible with a poorly designed system. It is however just as likely that a poorly designed pivot, using bearings, will also have a very short lifespan... I know of a few but won't mention any names.
I also know of a few poorly designed bushing systems and again will keep my mouth shut.
You'd be surprised to find out how many company's out there are making bikes and don't have a single engineer on staff... and again I won't mention any names.
So it basically boils down to the designer and if he has a clue what he's doing. Luckily our Masters of Mech. Keith knows a thing or two about engineering and something called tolerances.

Basically the bushing should not be able to be tightened beyond a certain point or else they will drag on the shoulder and prematurely wear. When a bushing prematurely wears, play develops and the rider tries to tighten the pivot further which only causes more wear. The way our axles were designed they will tighten to a certain point maintaining the correct tolerance for the bushing and you won't be able to overtighten them.
We've honestly been riding the same set of bushings on the Rampant, and Runes that we've had since early last spring, they've not been greased and have seen almost daily runs at whistler all summer, been to all our demo days, and have booked what must be thousands of miles by different riders. The pivots are as tight today as they were when we first got the bikes... I'll keep you updated on the exact date I notice play in any of them and how long it will be until we have to swap them for a new set.
So basically not all systems are created equally. I know its hard for the rider to wade through the BS, but I'm happy to report riders are so much more informed then they used to be and it will serve them well in their choice for their next ride.
Of course we welcome comments and the chance to discuss the principles of what makes a decent design.