Since acquiring the Bianchi Methanol 29 FS the boundaries of my riding have been pushed, I found more speed in the rough terrain and that has meant a change in certain practices. I have always been a weight weenie, scouring for the lightest parts available, but more and more I’ve been steered in the direction of strength and rigidity for added performance, rather than simple weight savings.

This is one such case. previously I would simply bin the standard supplied heavy steel quick release skewers supplied with any wheelsets in favor of an anodized light weight Ti pair to drop the weight about 100g. On the road this is still easy to do without too much drawback, but on the MTB, and especially 29er I have been forced to solidify my front end.

I have a RockShox SID XX WC fork, bought in the lightest (and at the time only available) configuration with 9mm standard dropouts. My Ti skewer was flexy and I was feeling it’s shortcomings on the fast and stiff Methanol. Changing the lowers to the 15mm Maxle version was the obvious choice, but with no stock available and a fair sized price tag, and marginal weight gain this wasn’t an immediate solution to a problem I wanted sorted out lightning quick. A few calls later and I’d sourced a DT Swiss 9x100mm front axle as supplied on some S-Works models and further investigation revealed I didn’t need to modify my forks and the perceivable stiffness between this and the 15mm maxle was minimal or none at all. As a bonus it only weighed 57g!

I set about a wild goose chase which turned out to be a wild ghost chase, as Easton do not make a 9mm bolt thru adapter for their front wheels, more browsing told me that it was possible to do a self modification to get them to work:

Step 1: Machining

Luckily for me I work next to some boys that have a lathe, some brief instructions, finger pointing and a couple of vernier measurements later and my previously 5mm hub axle was now re-bored to a 9.1mm diameter. They machined down until flush to the 90 degree surface it’s just beneath the gripper surface so that the clamped up wheel would grip.

9mm Axle (4)Fitment

Rather excitedly I refitted the axle into my front wheel only to quickly realize the shortcomings of my haste. I had in the process of machining the oversize axle, machined off the two 5mm allen key ends necessary for tightening the axle up… I tried to tighten it in vain with my fingers before removing it and staring at it for a while thinking of a solution.

9mm Axle (1)

Problem Solving

The solution would be two-fold, I would need to make the necessary adjustments to the actual axle ends, as well as making a tool to fit my custom solution, or create a solution for a known common tool. My thoughts led me to a dual drilled hole in the ends for using circlip pliers, as well as skimming the ends for a cone wrench – not pretty as the result would be bare silver exposed aluminium. In the end I settled on a slotted inner recess that could be made for a big flat screw driver or a custom tool that I would make to suit, easily bending and shaping something to fit. The ends filed down super quick with a sharp file and then a really simple solution for a tool followed shorty thereafter.

9mm Axle (2)

Specialized Tooling

As they say the simplest solution is best and two identical tools were needed I measured up the filed recesses and cut away two large washers providing decent grip, besides the necessary torque is low. It’s also nicely out of the way to hold while adjusting the bearing tension with a 22mm wrench.

9mm Axle (3)

Ride

The new axle clamped up superbly, the RWS ratchet system is nice in that you can torque it up high and still keep the QR lever facing the right way, plus it can never flip open, good idea! It’s a little slower to get on and off but that’s small fry, if you need to remove your wheels in a race you have bigger issues!

Since its a 9mm system I can still use my wheel in any QR fork, plus I bought the genuine 15mm axle conversion just in case…

The wheel certainly feels stiffer, I can tangibly feel its more willing to react to directional changes and I’m less hesitant to take hits on the front. I’d also expect less torque flex affecting the braking and rotor rub. Overall the weight of the system is still 30-40g lighter than going to 15mm, and a lot cheaper too. Id consider it a worthy upgrade for anyone wanting get stiffer on the front without having to completely change your forks or lowers.

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