This won't interest athletic folk with handlebar six inches below seat height and only a couple of centimeters of threadless headset spacers. However there are plenty of home tinkerers who love long steerer tubes and handlebars level with the seat or even higher. They finish up with this look.
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| 8cm of spacers |
I first considered the possibilities of replacing half a dozen spacers with a single long tube spacer when fitting a cheap new fork to a ratty old MTB. I wanted the bars high and my junk box was devoid of 20mm spacers. Repelled by the idea of a teetering stack of 5mm and 10mm spacers, I soon discovered I had a likely looking length of scrap 32mm aluminium tube. Yes, it was a close sliding fit over the steel 28.6mm steel steerer tube.
The scrap tube was roughly hacksawn to a fraction over-length then finished with file, vernier caliper and engineers square so that the ends were both parallel and square to the tube axis A final check with a surface plate and square confirmed that the simple hand filing job was accurate enough for the purpose. It would be simpler and quicker to face the spacer ends in a lathe with a big enough spindle hole behind the three-jaw chuck but the machine I have isn't that large.
The idea worked so well on the ratty MTB that I soon decided to extend it to nicer bikes in my herd.
A visit to a Capral Aluminium warehouse secured 6.5 metres of 32mm round tube for $17, enough for a lifetime of bicycles. It's 6060 T5 aluminium with a smooth mill finish.
32mmO.D. minus 2x1.6mm wall thickness = 28.8mmI.D. It seems to be a common size in other metric nations besides Australia.
Citizens of places persisting with Imperial units of measurement should start by looking for inch and a quarter tube with a suitable I.D. Take a vernier caliper with you and look for a touch greater than 1.125" I.D. or a sixteenth inch wall thickness.
The 1.6mm wall thickness of my chosen tube is somewhat thinner than a bought headset spacer. The spacers I have measure anywhere between 2.3 and 3mm depending on where they came from. But I believe that my thinner walled single tube spacers are in no danger of being crushed by the forces developed in ordinary road or bike trail use. Persons engaging in extreme off-road riding are unlikely to want tall steerer tubes and won't be trying this mod anyway.
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| Marking jig, 200mm double cut bastard file, engineers square, 32mm aluminium tube stock. |
Pictured above is a simple wooden marking jig. The length of roughly cut tube is rotated against a sharpened drywall-screw scriber. This provides a line to file down to before I start checking for squareness with the steel square.
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| Raw or Painted |
The mill finish of the tube is quite attractive. It could be left as is, mirror polished and clear lacquered or simply given a coat of rattle-can gloss black.
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| 8cm spacer tube installed |
My tube is actually a closer fit than my assortment of bought spacers. I put plenty of grease on the steerer tube to avoid corroded steerer/stuck spacer syndrome in the future.
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