5mm qr to 9mm qr, w...
 

[Closed] 5mm qr to 9mm qr, worth it?

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Won a new wheel on ebay with a pro 4 front hub which needs new end caps.
Currently running a standard 5mm qr on the front of my jamis which is flexy as hell and wondered is it worth setting this wheel up with a 9mm qr until I can afford new forks or is the difference negligible?
Is it just a case of whichever works out cheapest?


 
Posted : 12/04/2019 10:35 am
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9mm is the standard, it refers to the size of the axle it goes through rather than the size of the QR skewer.


 
Posted : 12/04/2019 10:41 am
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I know this but I can either run a standard 5mm qr skewer with the forks sitting on the 9mm portion of the end caps or run different end caps to run a full 9mm qr axle which the forks sit on


 
Posted : 12/04/2019 10:45 am
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Like this ?

https://www.superstarcomponents.com/en/9mm-front-qr-through-axle.htm

Then yes they make a difference ime, if the back end is flexy too 10mm one on the rear helps too.


 
Posted : 12/04/2019 10:49 am
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it's a stiffer QR, so in theory should be about the best you can get from a QR fork.

It does help a bit, and if it's easy enough for you to do, I'd say it was worthwhile.


 
Posted : 12/04/2019 10:49 am
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Will give it a try then. Probably the only downfall with the bike as the rear is 12x142 already.


 
Posted : 12/04/2019 10:51 am
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I’ve got a RWS 10mm bolt through in the rear of a steel hardtail. Not sure if it makes it stiffer but it has stopped me snapping the axles on the (superstar) hub.
They do a 9mm version as well but more expensive than SS. It tightens very tight. Not a qr as such.
https://www.dtswiss.com/en/products/hubs-rws/rws/9-mm/


 
Posted : 12/04/2019 10:59 am
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RWS 10mm bolt through

Yes - this DT Swiss RWS might work.
Or not.
The DT Swiss RWS is not a very good solution for "flexible frames". The thing likes to loosen...


 
Posted : 12/04/2019 12:43 pm
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Gone for the superstar axle, seems to have decent reviews so worth a look for £7!


 
Posted : 12/04/2019 12:51 pm
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Yes, I had one of those and it worked fine. The SS one is quite heavy from what I recall though.


 
Posted : 12/04/2019 12:56 pm
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A long time ago we used to make an On-One 456 Hub that was like this. Stiffened things up well. Sadly the bearings were nearly impossible to change when they stiffened up too.


 
Posted : 12/04/2019 2:06 pm
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I'm confused. Do these bigger QRs not still just clamp the sliders on to the hub end caps? Is the benefit that they can do it harder?

A long time ago we used to make an On-One 456 Hub that was like this.

I think I've got one in my spares box, it's a nice chunky BULB-like thing, though I'm now quite glad I've never built into a wheel!


 
Posted : 12/04/2019 2:26 pm
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Do these bigger QRs not still just clamp the sliders on to the hub end caps? Is the benefit that they can do it harder?

Yup. But the spindle holding the two ends of the QR together fill the (9mm) dropouts, rather than being somewhat smaller than the dropouts, with a theoretical increase in rigidity.


 
Posted : 12/04/2019 2:37 pm
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But the spindle holding the two ends of the QR together fill the (9mm) dropouts, rather than being somewhat smaller than the dropouts, with a theoretical increase in rigidity.

Well, they're pleasing beefier than a standard QR but unless they're an interference fit in the dropouts I'd be surprised if they made a measurable difference, but I've never ridden one and the consensus^ seems to be against me on this. SS calling theirs a "Through Axle" seems to be pushing it a bit though.


 
Posted : 12/04/2019 3:01 pm
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I noticed a difference going from qr to 9mm RWS. It was particularly noticeable on rocky descents. Not as big as a change to a 15mm axle though, but worth £30.


 
Posted : 12/04/2019 4:26 pm
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I switched my hopes to 9mm through front

The front made a big difference.

I used a superstar axle at first as linked but they gunk up and are junk after a while.

I replaced with a DT RWS much much better.

I also fitted a 10mm DT RWS to the rear but didn't notice any difference, but the frame is stiff anyway with a one piece rear triangle (turner flux), on a bike with a pivot near the dropouts you might notice a big difference.


 
Posted : 12/04/2019 4:38 pm
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I've read a few bits of MTBR forum feedback on 5mm vs 9mm.

I do use DT's 9mm RWS every chance I get on the kids bikes, but there's a suggestion that some brands 9mm axle is no better than a 5mmQR.


 
Posted : 12/04/2019 5:43 pm
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Tbh, 9mm front solutions like the DT RWS, Spesh Stout or Superstar ‘QR’ are really much closer to being TA’s than the spindly chopsticks we think of as ‘QRs’. You just need to see them side by side or hold them to realise there is a difference. If I had a bike with a fork with QR dropouts, I’d run one of these every time. They really tighten the front end up.

At the back, a 135x10 also stiffens the tail noticeable, although not always to everyone’s taste.

£ for £, this is one of the best upgrades that can be made on a QR bike if you have suitable hubs IMO.


 
Posted : 13/04/2019 5:13 pm
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Is there a list or reference as to which hubs can be used with the 9/10mm qr? (Are they the same thing as the 9/10mm through bolt some people refer to?


 
Posted : 13/04/2019 5:39 pm
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My Spesh Stout kept undoing itself, presumably due to effect from braking. I had to keep a close eye on it.

Interesting discussion as there must be plenty here using older forks/hubs.


 
Posted : 13/04/2019 11:12 pm
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Guessing the stout is external cam like the Superstar.

Given how a standard QR hub is constrained I'm not sure how using a hollow thru axle in tension is going to make it any stiffer than a hollow fixed axle in compression as the clamping surfaces as nominally identical. I'm sure there is an easy equation out there involving the second moment of area and bending moments but that part of my brain is on holiday at the moment.

I'd be more inclined to recommend people stop using shitty external cams and instead just stick with proper internal cams that don't come loose. That would certainly make for a stiffer ride.


 
Posted : 13/04/2019 11:47 pm