Milling Down a Headtube?
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Milling Down a Headtube?
Hey all, I have nowhere else to ask this question, so I figured this section of the forum would be best.
Anyway, I have a steel 29er frame that fits me perfectly except for the fact that I can't seem to get low enough on the front end. I know, the easiest step is to get the next size down, but having ridden that size, I feel overly cramped which is something I definitely DO NOT want while racing XC.
So, there's about, oh, I'd say a good usable centimeter of steel on the top of the head tube before I would even consider it being an issue of interfering with the weld to the top tube.
I know most frame building shops have a lathe with a headtube cutter used more for facing than milling, but I figured I could pay for the cutter to be sharpened after anyway.
After that incredibly long, rambling into, I'm just curious if there are foreseen structural issues with milling down my headtube? I know milling from the bottom can alter the steering angle, but I can't figure out any other downsides to taking the headtube down 5mm on top.
Anyway, I have a steel 29er frame that fits me perfectly except for the fact that I can't seem to get low enough on the front end. I know, the easiest step is to get the next size down, but having ridden that size, I feel overly cramped which is something I definitely DO NOT want while racing XC.
So, there's about, oh, I'd say a good usable centimeter of steel on the top of the head tube before I would even consider it being an issue of interfering with the weld to the top tube.
I know most frame building shops have a lathe with a headtube cutter used more for facing than milling, but I figured I could pay for the cutter to be sharpened after anyway.
After that incredibly long, rambling into, I'm just curious if there are foreseen structural issues with milling down my headtube? I know milling from the bottom can alter the steering angle, but I can't figure out any other downsides to taking the headtube down 5mm on top.
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Could be done, probably best though to just carefully cut off most of the excess tube (hacksaw) and then use a file and finally the facer to clean up the cut, rather than milling all the tube down in one single operation. If there is any sort of re-inforcement band on lug around top of the TT, you shouldt obliterate it.
How about first going to a stem with less rise (or flip a stem for negative rise like a road stem).
How about first going to a stem with less rise (or flip a stem for negative rise like a road stem).
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I'm currently running a -17degree stem with flatbars. Too high.
GrayJay - there is a reinforcement band on the top - how much should I leave? Measures about 1.5cm in height.
Additionally, does anybody know of a lower stack stem than a Thomson X4? It's what I wanted to buy when all was said and done.
GrayJay - there is a reinforcement band on the top - how much should I leave? Measures about 1.5cm in height.
Additionally, does anybody know of a lower stack stem than a Thomson X4? It's what I wanted to buy when all was said and done.
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Looks a bit odd, but you could always use a high-rise stem of more than 17° flipped to angle the bars down further.
Have you tried a stem that is longer than your current stem? A bit of additional extension might substitute for the low height. If you have a shock fork, lower travel setting would also help to bring the front end down.
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If the bars are noticeably high, the 5mm or less removed from the headtube isn't gonna make much difference. Move saddle- change/flip stems- different stem- headset with less stackheight- remove headset spacers- different bars, etc are more logical solutions.
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How about a profile view of the bike?
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