Converting Quick Release Skewer to bolt-on axle

Is it possible to convert a quick release axle to an allen bolt axle, i'm not talking about an allen skewer, I mean tapping the axle and then using bolts on both sides to attach the hub to the forks. This would be for a front wheel.

I'm guessing the above is not possible but a new axle could be machined to do the job.

You can buy the axles for this. Some MTB brand used to sell them, forgot which though. What front hub do you currently have?

Alternatively, you could just get a new hub. Lots of allen key ones available.

Generally, you will find that the front (9mm) hollow QR axles don't have a massive amount of meat inside them, to tap a thread into, its do-able, but wouldn't produce the strongest axle in the world.

Personally, I would machine up a new Axle. YEH.

You might be able to get an M7 bolt into a 9mm axle but your chances of finding an M7 bolt are slim.

I helicoiled an M6 thread into a pair of Hope hubs with QR axles, and used these with great success. A nice, neat solution, and a good alternative to a QR skewer, if it's done well.

what do you mean by helicoiled do you mean tapped? isn't helicoil for stripped pedal threads?

A helicoil is an insert which is put into a hole where a thread which has previously been stripped. It self taps itself deeper than the original thread.

I've tapped normal steel QR axles for M6 screws on a couple of front wheels; although the bore is slightly over the correct pilot size for M6 they work fine. Just don't go mad tightening the screws to avoid stripping the thread - about 4Nm is plenty to hold a road front wheel. Don't do it on a disc brake MTB wheel, stick to a proper enclosed cam QR at the very least.

I've even done an aluminium one on my roller bike, although I might baulk at that for road use.

+1 to mdcc's advice- helicoiling it for M6 would be gilding the lily for most applications.

Welcome back Mr K.

You can buy the axles for this. Some MTB brand used to sell them, forgot which though. What front hub do you currently have?

Alternatively, you could just get a new hub. Lots of allen key ones available.

i've got a marin with 5 sided allen sockets to hold the wheels on

I'm still confused as to why you would want to though.

Reduced CdA for time trial bikes, elimination of the QR handle for track bikes.

CdA? What's wrong with using an allen key skewer? Or is that too heavy for some people?

I'm doing it for weight its for this hub

I dont see the need to have all that metal of a skewer inside it, also don't like skewers as they aren't symmetrical.

CdA?

CdA is drag coefficient times area. It's best to consider this product rather than Cd on it's own, as total aerodynamic drag is determined by both the shape *and *size of an object.

Allen key conversion on my front RS30, using countersunk screw and custom cup washer, reduces frontal area substantially compared with an Allen key skewer.

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I see. That is a fair lump of surface area removed. I've not seen them mass produced before though.

I seem to recall mdcc_tester posting somewhere an estimated value for reduced CdA with this change - anyone know where?

There's some aero skewer options in this lot..
http://www.tririg.com/articles.php?id=2013_05_Skewer_Shootout&page=1

Found it: http://www.lfgss.com/thread16289-93.html#post3705855

Dunno if serious...

"0.0004m² reduced frontal area out a total CdA for duffers like us of about 0.3m² is 0.13%, that's nearly 2s in a 25 minute 10, more than I was expecting."

Serious, but wrong. That 0.0004m² needs to be multiplied by Cd to get the reduction in CdA. Treating the axle as an isolated cylinder with it's axis orthogonal to the flow, the Cd is about 1.2, so the time saving could be as high as 2.5s :-)

The total area given was for the HED axle conversion, which was substitution of screws for a conventional Allen-key skewer and a reduction in the axle diameter. Getting rid of the QR lever will make the saving bigger than stated, but just converting from an Allen-key skewer to the low profile screws will reduce it a bit.

The French were using these Io wheels at London 2012 with the middle of the axle removed

Not sure if aero benefit or psy-ops

Wow, that's mental. I never saw those.

I might invest in some low profile skewers for short stuff then.

The flat-ended ones look very compact and aerodinamic :)

I've got a quick skewer question. Wasn't sure of the best place to ask.

I've recently got a front wheel with a bolt on front skewer. I've got alpina wing TT forks and they are quite meaty around the dropouts and there only seems to be 5-6mm of the skewer threads engaged with the nut. If I ride the bike like this will I die?

Get a new one. Halo do two sizes, standard for up to 6mm thick fork ends and XL for up to 11mm.

I've ordered halo, but think I've only ordered the standard size...

A quick measurement of the fork ends reads as an inaccurate 7 or 8mm.