QR15 or standard 9mm?

gixernick

I'm uprading the forks on a Giant Trance X3 from Rockshox Recon. It's a 5.5 inch travel. I'm almost cetain I want the Fox Float 32 FIT 140's.
However the LBS has asked whether I want standard 9mm or QR 15? QR15 are about £30 extra with £60 extra for a hub and £25 for a wheel rebuild. So puts the price up quite a bit. However fom looking round it will stiffen the front up, but also future proof my bike a bit. There seems to be less 9mm QR stuff about like it's being gradually phased out. With the forks and all of the above outlay they are going to have to last for a good few years!!
Your thoughts views are appreciated (most of them any way).

supersonic

How much do you weigh, and how hard do you ride? Fox 15QR improves torsional stiffness by 15%.

gixernick

100kgs, 6'7" and sadly my ambition far outweighs my ability so things do take a beating.

supersonic

I'd probably go for it, though if you want to see even more stiffness, choose an RS fork with 20mm axle.

mrmonkfinger

If you go QR15, it'd probably be a better bet to sell your existing wheel, and buy a new complete wheel with a hub that can swap standards (superstar switch or hope pro evo or something like that).

Unless you do wheelbuilding yourself, "swapping hubs" is a pricey route to go.

.blitz

As above std QRs are crap esp on front wheels.

20mm thru axle is where it's at there's no point in having stiff forks then using a bit of thick wire to attach the wheel.

Reckon on £110-ish for a Hope/DT/Mavic wheel which will be considerably better than rebuilding your existing wheel.

supersonic

As above std QRs are crap esp on front wheels.

Depends on so much! A 9mm QR Menja is stiffer than a 15mm Fox Float! And even like for like some people just don't feel any difference. I am running QR XTR hubs on Rebas, crap they are not lol.

MountainMonster

I hear you guys on the like for like comparison and no different noticed. I switched from QR to 20mm, and never noticed a difference at all, may be inexperience, may be not much of a difference in real applications, who knows?

bennett_346

The thicker QR that DT swiss use on their wheels is good, i have that with my revs and it feels just as stiff as my old 20mm pikes. Not sure how much of that is down to the forks themselves though.

supersonic

It doesn't increase stiffness though, is not designed to! It replaces the QR as a more secure wheel fitting.

bennett_346

supersonic wrote:

It doesn't increase stiffness though, is not designed to! It replaces the QR as a more secure wheel fitting.

Well you learn something new every day! Guess my LBS was talking bullshit!

supersonic

The hub may have been stiffer than others you have used, or even wheel build.

toasty

By thicker DT Swiss QR, are we talking 9mm RWS thru axle here? If so, how do you figure it doesn't increase stiffness?

bennett_346

Toasty wrote:

By thicker DT Swiss QR, are we talking 9mm RWS thru axle here? If so, how do you figure it doesn't increase stiffness?

Yeah but it isn't a thru axle is it?

supersonic

Standard RWS is a ratcheted skewer.

The other type is a 9mm "through bolt" rather than through axle (ie does not thread into oversized fork legs or dropouts, which combined with the 15mm or 20mm axle should theoretically make the set up torsionally stiffer) it still uses the basics of a QR system ie both sides of the fork retained againset the hub in compression.

A German mag tested a convertible rear hub with XTR skewers, Crossmax skewers and a DT RWS 10mm through bolt. The XTR and Crossmax were both about 15% stiffer torsionally!

cat_with_no_tail

Wait, I thought the "standard" QR was 5mm, not 9.

When I got my 9mm QR from superstar is was significantly thicker than a regular one (almost twice as thick in fact). And required different fittings on the hub.

The dropouts on most bikes are 9mm, the QR skewers are not.

No idea if a 9mm skewer is *really* stiffer than a 5mm one though as I have no means to test it impartially.

bennett_346

Cat With No Tail wrote:

Wait, I thought the "standard" QR was 5mm, not 9.

When I got my 9mm QR from superstar is was significantly thicker than a regular one (almost twice as thick in fact). And required different fittings on the hub.

The dropouts on most bikes are 9mm, the QR skewers are not.

No idea if a 9mm skewer is *really* stiffer than a 5mm one though as I have no means to test it impartially.

Yeah that's all correct. I would of though it would increase stiffness but i suppose it is to do with the dropouts being the same as to why it wouldn't be stiffer?

toasty

supersonic wrote:

A German mag tested a convertible rear hub with XTR skewers, Crossmax skewers and a DT RWS 10mm through bolt. The XTR and Crossmax were both about 15% stiffer torsionally!

Ah, you're quoting the 2009 random German magazine test.

http://forums.mtbr.com/ibis/forks-qr-vs-qr-15-measurements-bike-magazine-481960.html

In which case Fox F120s are 15% stiffer then Rebas, in fact a QR Talas is stiffer than a Maxle Pike Air. Regardless of the fact you can tell these figures are rubbish by riding both for 10 minutes.

On the back end you'd also be better using a Mavic QR, they're stiffer than XTR apparently. Hmm.

The stiffness values they get back are going to be so dependant on the hubs and end caps used for each.

bennett_346

Then again 15% stiffer than something that isn't very stiff still isn't very stiff!

cooldad

bennett_346 wrote:

Then again 15% stiffer than something that isn't very stiff still isn't very stiff!

TLMO

gixernick

Sooooooo...... that doesn't help much. Think I've just started a big argument.
Think I'll go with the QR15 and have the Hope hub put in my rim.
Thanks everyone.

toasty

Basically they're a bit more solid feeling than standard QR, you also get the bonus that your wheel is securely attached, so couldn't be pulled out, like it could with QR. If you have the choice of both, go QR15 every time.

Whether you notice the difference will be down to your riding/weight etc.

20mm maxle used to be stiffer, without a huge weight penalty. It seems to be getting phased out though, due to better hub compatibility with 15mm.

bennett_346

I think a lot of it is in your head anyway. If you couldn't see the hub and dropouts and were made to ride a ike with normal QR and 15/20mm thru axle you'd unlikely guess which was which first time.

supersonic

Toasty wrote:

supersonic wrote:

A German mag tested a convertible rear hub with XTR skewers, Crossmax skewers and a DT RWS 10mm through bolt. The XTR and Crossmax were both about 15% stiffer torsionally!

Ah, you're quoting the 2009 random German magazine test.

http://forums.mtbr.com/ibis/forks-qr-vs-qr-15-measurements-bike-magazine-481960.html

In which case Fox F120s are 15% stiffer then Rebas, in fact a QR Talas is stiffer than a Maxle Pike Air. Regardless of the fact you can tell these figures are rubbish by riding both for 10 minutes.

On the back end you'd also be better using a Mavic QR, they're stiffer than XTR apparently. Hmm.

The stiffness values they get back are going to be so dependant on the hubs and end caps used for each.

The fork test is flawed when comparing one standard to another - the reason is how they were tested. The weight applied to the set up for torsion is going to provide a bigger lever with 20mm axled forks as 9mm is a lot narrower in stance. I'd have liked to have seen the travel set the same for true like for like measurements. This is why I didn't want to quote any of the 9mm vs 20mm fork figures from the test lol. However with the rear set up the frame will be the same, so these variable are at least minimised. I agree that the hubs should make a difference too.

Bench tests a side (we have also done some at WMB!), it is how it feels on the trail to you, regardless of theory. Fork for fork, I cannot tell any difference with RWS or moving from 9mm to 15mm. Others can, and it seems heavier riders and harder riders notice it more. In terms of stiffness, I notice a few PSI in the tyre wall quite a lot!

RWS is very secure, will not come undone if caught by an objecton the trail, is pretty light, so has its place. With their own hubs the thru bolt theoretically could be stiffer as the hub internal bore will be larger diameter to accomodate it.

toasty

supersonic wrote:

Bench tests a side (we have also done some at WMB!), it is how it feels on the trail to you, regardless of theory. Fork for fork, I cannot tell any difference with RWS or moving from 9mm to 15mm. Others can, and it seems heavier riders and harder riders notice it more.

I think it's just a trail fork thing, given the focus is now being as light as possible, yet keeping as much travel as possible they'll go as close to the mark as they can, aiming squarely at the bulk of the demographic. Being 6'6" and weighing about 15 stone I'm sat a bit above the average, so bits that can be flexy, generally are

I was riding on a Pike for a while, the difference with my Float was night and day, far more direct feeling. It was a cheapy oem model and the damping wasn't up to much, along with stripping a pivot bolt on the Pitch within a few rides of owning it, I decided I couldn't be bothered and sold it before it lost much value

supersonic wrote:

In terms of stiffness, I notice a few PSI in the tyre wall quite a lot!

Definitely! I actually put an inner tube back in my rear last weekend after months of running tubeless, every time I've gone tubeless with standard tyres on my Flows I've regret it. I understand the logic, just find it curiously draggy on the trails on the back wheel. Flexy wheels are one thing that drive me bonkers too, I think my XT factory wheelset are half of where my irrational hatred of Xt hubs comes from, I had a set of Hope Hoops on 355s too, that was a mistake

supersonic

I nearly had a big off last week due to the tyres bending over! 28psi, and hit the bottom of ramp hard, slightly off centre. As I squared it back up, nothing happened, it just sort of squidged and dug in. Had the same with tubeless too, but they burped air when this happened, so I too have dumped tubeless for good.

The Psylo at full travel was a fork I noticed quite a bit of flex, but mostly in slow speed corners and near stalls with the front brake on. As I shifted my weight you could see and feel them bending over. I used to run a 25mm stanchioned Indy too lol, would be fun to try that just to see!