conspiratemus1

Our tandem built in 2007 came with an AlphaQ X2 carbon fibre fork (with CF steeer), drilled for a short-reach rim brake. Several years ago we installed a disc-brake capable CF fork to give more confidence descending long curvy descents in Europe. (The bike already had a disc brake mount on the rear.) But for home here in Southern Ontario where one never brakes for more than 5 seconds, the rim brakes perform just fine (and my perception is they start stopping quicker than the discs do and they look nicer.) So the AlphaQ goes back on for all our local riding the rest of the season. The act of installing it allows for inspection to look for damage, although admittedly I do not pop the crown race to look under there.

So the question is, do any of you with Alpha Qs (or any other elderly carbon-fibre parts) worry about the risk of failure as the parts age? What do you do?


The AlphaQ was (and is) a highly regarded tandem fork and it was never clear to me why the manufacturer discontinued them (and all other composite products), other than the general rule that every business has to follow: "It's not how much it costs, it's how much it makes." Obviously the manufacturer is no help now for advice.

Anyway, on the advice of the bike-builder, we have decided to retire the AlphaQ, pristine and undamaged as it is, on the premise that once you start thinking about it, you're not fully enjoying riding any more. We're looking into having a steel rim-brake fork built or perhaps we'll just transition to full-time disc brakes (which latter was actually the builder's advice.)

Doge

I had to tear apart one of their seatposts lately. If the fork is anything like that post, ride it until it cracks.
See my Co-Motion post. I live in SoCal. I replaced front and rear disc brakes with rim brakes. I saved 2# on the front brake and fork replacement alone. I had a disc and wound-up. I went to the Enve. Tandem is about 400# riders and bike.
I'm not concerned.
I used to stand and sprint more, I might setup differently for that.

tandem rider

In 2003 I bought a Co-Motion with a Wound Up carbon fibre fork. It had a rim brake as Co-Motion only put discs on the rear wheel at that time When the bike had about 25K miles and 6 years old the bike was overhauled. I asked about the life span of the fork. Wound Up did not give a definite answer but offered to sell me a new fork under their trade in crash replacement policy and I replaced the fork. Wound Up took the fork apart to inspect it and said it was structurally fine after 6 years and 25K. I'm not sure this answers your question as the rim brake probably puts less stress on a fork than a disc. It is also a different brand but maybe it says something about carbon tandem forks.

Dave Mayer

Tru Temper (Alpha Q) made a great fork. However, they have to be setup and installed in a precise way. I've seen several serious screw-ups with the prep in these forks, some by pro mechanics.

On the versions with the carbon steerer tube, the 4" long alu insert has to be installed after the steerer is cut to size. The insert has to be carefully epoxied into place. The bottom of the insert has to extend below the level of the upper headset bearings.

​​​​​​​These forks should never be resold, given the risk of someone shortening the steerer, and installing on another bike, with the potential for serious injury.

conspiratemus1

It sure does! Thanks much.
Les