Originally Posted by
HillRider
Uhhh no, if you really read what Sheldon wrote and what the OP first proposed you would realize the two are not at all the same. Sheldon was discussing leaving a threadless steerer extra long and using the extra length to allow the handlebars to be placed higher. He did not say anything about splicing an extra length of steerer onto the too short one and using it to fit a threadless headset.
I didn't say they were the same. I said what Sheldon proposed was worse.
There are several of companies making those steerer extenders/converters. There is absolutely nothing wrong with using them as they are designed and marketed to be used...which is to extend the unthreaded portion of the steerer and use it
just as you would any other extra long threadless steerer.
The OP wouldn't be "using it to fit a threadless headset". He'd be using it to fit the stem on an otherwise too short steerer and the only thing he'd be sacrificing is the top cap, but there are plenty of perfectly reliable ways to tension a headset that don't involve a top cap from expanding spacers to using a piece of string. As I said, Sheldon Brown even says you can do it by simply leaning on the stem, although I personally prefer a more careful method.
The threading on the steerer is irrelevant. It's just a steerer too short to fit the stem and extending it is probably
even safer than extending a steerer to raise the bars because there's less leverage.