Tuesday, February 9, 2010

Torqued.......

So I was working on the "Disenchanted Ones" bike the other evening. He was having what he thought was a problem with his new-used ceramic bottom bracket. So he brought it over for me to swap out for an FSA. Of course the FSA would not work with his SRAM Cranks (STUPID). So I put the ceramic back in and tightened it up. Now, like all new 2 piece cranks they have a torque to which they want you to tighten the crank. The problem I have found though is that, when the crank is new this may work, but take it on and off a couple of times and you can through those numbers out the window. After tightening the bolt I noticed that the crank had a little play in it side to side and I am pretty sure that this is what he was noticing when he was riding. So I tightened it to the point wrere the play was gone, the cranks turned smoothly, and I called it good. I told him to keep an eye on it but I am pretty sure it will be ok.

Speaking of torque..............

I have often wondered about carbon handlebar manufacturers. They almost never publish torque specs for their bars but instead rely on the torque settings recommend for the stem clamping surface. I suppose that they have manufactured their bars to withstand a torque much higher than the manufacturer recommends, but in the end does that relinquish them of any responsibility if you do damage the bars?

That reminds me of a story..........

So a very good friend purchased a bike. The shop built it up and torqued everything to spec. For whatever reason, many months later, he goes to another shop for a "Professional fitting". Now those of you in the bike business please take no offense. Having somebody that is knowledgeable in bike fitting, set you up on your bike initially is a great idea. I cant tell you how many times I have seen somebody sell a bike to a person just because it was on the floor, and they could move product that day. Right or wrong that happens., usually to people buying comfort bikes or novice riders. But even Andy Pruitt will tell you, "Most standardized fit systems will get you within 2cm of this fictional "perfect Fit". At the Boulder Center, we can get a little closer. But over time your body will lead you to make adjustments that will bring you within this "Fit Window" of a centimeter on either side of your virtual "Perfect" measurement." In other words if you have a fitting done and after a few good rides you are not comfortable, you probably need to make a change. So many people get fitted, think that is how they are supposed to be, and no matter if they are comfortable or not, continue to ride that way.
Anyway they recommended that he, a guy that spends 95% of his time on the tops of his bars, should get a narrower set. So he complies and they offer to give him a credit for his old bar. (Good for them),. Except they later tell him that whomever had built this bike had over-torqued the stem clamping bolts and that the bars were ruined. So he went back to the original shop and explained to them what he had been told and that he wanted a new set of bars, which the shop was happy to do for him but not without explanation and calling out the other shop. First of all to tighten something to a point to which ti will not move under force you must first engage it, IE. deform it without damaging the structural integrity of the materials. If you don't it can break loose and spin or just plain break.anyway the shop sent the bars back to the manufacturer. Come to find out, there were some bars that were produced that had arrived a little under the diameter spec, which these particular bars did, and that there was no structural damage done.
Now it was pretty obvious from the start what was going on here. The other shop was trying to gain a customer, not through good customer service, but through misleading a potential customer. In the end the truth was found out but unfortunately many customers are lured away from a shop that truly has their best interest in mind for a shop that is only out to make a quick buck. This happens in all aspects of business so beware.
If I remember, I will someday tell the part of the story where the other shop tried to tell the same customer that his front wheel was on backwards.