QR15 Your Views

CustomReign

Hi,

I have read that the QR15 axel does not feel any different / offer any real benefit over a 9mm axel. (as opposed to a 20mm axel)

Could any QR15 riders advise please before I spend my pennies?

CycloRos

Can't comment on the QR15 as I've never tried but the difference in stiffness between 9mm QR and 20mm Maxle is huge and certainly worth the investment.

I've read some good reviews about QR15 and I'm sure it would be an improvement over 9mm just not quite the difference you'd feel going to 20mm Maxle.

dave_hill

I honestly can't see the point of QR15.

I mean, we've already got 9mm Q/R and 20mm bolt-through (and 25mm bolt-through if you count Specialized's offereings) so why do we need one half-way between?

It can't be much lighter than 20mm and I've also heard that there doesn't seem to be much difference in feel between QR15 and 9mm.

bomberesque

dave_hill wrote:

I honestly can't see the point of QR15.

I mean, we've already got 9mm Q/R and 20mm bolt-through (and 25mm bolt-through if you count Specialized's offereings) so why do we need one half-way between?

It can't be much lighter than 20mm and I've also heard that there doesn't seem to be much difference in feel between QR15 and 9mm.

I'm interested in this thread and it's a pity that we've had no users pipe up yet. I'd really like to have a hands on test of a 20mm vs 15mm vs 9mm (plus maybe the mavic 24 and Spec 25 aswell)

I half agree with you Dave, but there were reasons for the 15mm standard;

The positive connections between the ends of the lowers that any bolt through system provides has distinct mechanical advantages for stiffness over a QR, which is little more than a pair of pin joints in structural terms.

However, the hub length on the 20mm standard is longer than the 9mm. I guess this was to accommodate bigger tyres for the original target market of 20mm bolt through forks; DH and (maybe a little later) FR bikes. This means the stantions are further apart. Compare a Pike with a 9mm fork to see what I mean. It's only 10mm iirc but quite a difference in the flesh. This means that the crown is wider and the axle longer, both are then heavier. I'm not sure if this increase requires bigger stantions or whether this is more a function of the fork styles having them for overall stiffness / strength reasons. I've studied structural mechanics but don't practice it so am a little rusty

Where I agree with you is that I think 15mm was probably the wrong place to go with this idea and I believe was mostly market-hype driven. 15mm is a bit smaller than 20, thus it must be the lighter version sort of logic.

Generally, the bolt-thru concept is a structurally sound one, we just need a design that aims to use this additional efficiency to make the fork lighter instead of ever stiffer and stronger (of course this is a balance). I believe a "20mm-S" standard would have been better, using a short 20mm bolt through to maintain XC stantion centres and crown designs (which are already very light) then using the additional stiffness that this provides to take material out of the lowers and stantions to produce properly stiff structurally fit for purpose superlight forks. This was what Maverick claim to have done with their system.

All the above said, the stiffest XC fork that I've tried out *by far* was a cannondale lefty, I dare say it's as stiff laterally as my Pike, but I just can't shake teh feeling that the wheel's giong to come off at any minute :roll:

MrNero50

I run both 15 mm and 20 mm Thru axles and have in the past run 9 mm Q/R axles.

I will never go back to Q/R front wheels! The positive steering differences a 15 mm axle makes, over a 9 mm Q/R is noticable!

The difference between a 15 mm and 20 mm is not as noticable though!

CustomReign

Thanks MrNero50. That's the info I'm after. I think it was MBR that said there was no noticable difference between 9 and 15mm if I'm correct. This was on a couple of occasions.

bomberesque

a quick test you could do in a shop is place the front wheel between your legs and yank on the h-bars. As long as the bars are similar you'll get a quick feel for the stiffness of the set-up.

I'm surprised (and happy) to hear that 15mm seems closer to 20mm stiffness than to 9. A blow to my cynicism

When will they make a 15mm through SID then?

ride_whenever

don't forget the maverick 32mm IIRC

everyone knows that qr15 offers virtually nothing over maxle lite for the consumer, particularly with larger tubes being stiffer. What it does offer is a way around the patents for the manufacturers...

joshtp

I have 'zochi 44's with QR15 and compared to my old QR forks they are massively stiffer tracking, more precise, and they feel more sollid. i have never tried a 20mm though so i cant comment on that.

CustomReign

Hi,

I might look at the 44's if you think they're alright. My 20mm's have been Pikes and Monster T's. They weight 12lbs but steer better than my car,

supersonic

Speshes new inhouse QR forks use a larger clamping area which many report offers a stiffer fork.

Of course fork flex is in several plains: fore aft flex ie from braking is unnaffected by axle type as generally it is the steerer that flexes.

I think it does depend on the fork. Some 15qr will be stiffer than 20mm, some 9mm stiffer than 15.

joshtp

Im not saying the 44's are the best, and they only have a Qr15 on the top end fork (for aftermarket) which is suposed to have a shocking action, and poor reliability. i have the tst2's which are quite good, but dont normally have a QR15. i only have it becouse GT twisted 'Zochi's arm.... and also the 44's only come in 140mm, so may not be the right travel, and for that travel and class i would go for RS rev's with a Maxle light. But! f you dont mind buying the top end ones, dont mind (comparitively) poor performance, and a HUGE price tag, th 44's may be right for you!
*rant over*

nferrar

Yeah I think some people overlook the other aspects of the fork when saying a 20mm is much stiffer than a QR - I bet a lot are comparing two different types of forks. My only comparison is between 9mm QR 2007 Fox F80's and 20mm 2009 RS Rev U-turns - yes the Rev's track better when pushed but then I'd expect the QR version of them to over the Fox's.

SDK2007

The 25mm thru axle on the Specialized E150 fork is super stiff, especially considering the triple clamp and integrated stem. Probably on par with full DH rigs.

CycloRos

I do think RockShox 20mm Maxle Lite is absolutely spot on in terms of ease of use and advantage over standard QR. I honestly can't see myself changing to any other type of axle mechanism cos it's just that good.

Just look at the different fork applications its used on Reba, Revelation, Pike, Argyle etc... there's something there for every type of rider.

supersonic

I would say, that some people would not know the difference if you could test them blindfold.

Also have to consider the wheel - if you have a super light 20 spoke jobby, that will flex too.

Anonymous

im with sonic on this one, i reckon in a blind taste test, most folk would be hard pressed to tell any difference at all.

my 20mm lyriks feel no different in stiffness to the 25mm axle my e150s had. that said, i dont actually feel any difference when compared to regular 9mm on my other bikes. if i hold the front wheel between my feet and twist th handle bars there is a noticeable difference but i dont feel that out on the trail.

supersonic

I am not sure I could tell with some forks to be honest.

There is also another interesting factor here which I think Justin Loretz picked up on - the stiffer fork may steer better, but sometimes the slightly flexier one can track the ground and feel better because it will slightly deflect out of the way of some obstacles.

I have heard the same said about the rear end of some bikes, and steel afficianados will tell you this.

Anonymous

i noticed that in a review i read t'other day too, i found it a bit confusing, for years everyone has banged on about how fork stiffness is the be all and end all and now it is acceptabl, even desirable for a fork to bend all over the shop.

i cant help thinking random bollox is put into reviews even in the same magazine just to see how quickly in permiates into the bike riding zeitgeist.

CycloRos

sheepsteeth wrote:

im with sonic on this one, i reckon in a blind taste test, most folk would be hard pressed to tell any difference at all.

Well in a recent taste test conducted a couple of weeks ago I swapped out a Reba 9mm QR on a Mavic XM317 wheel and Shimano hub for a Pike 20mm Maxle on the exact same rim with a Hope hub. Now admittedly I didn't blindfold myself but there was most definitely a noticeable difference in front end stiffness.

How much of this is down to the difference in fork strength/stiffness and how much is down to the axle though is difficult to say.

Anonymous

well done

lawman

i reckon you can feel a slight increse in stiffness, but only if you find something reall fast steep and off camber or are really hauling along some singletrack. whether its worth the extra aftermarket is debatable but if it comes on a bike then great, i dont think id be too bothered if it didnt, but more is always welcome whatever it is. the main benfit i see is that thru axles are far more secure than grs for security and the wheel falling out :shock: