Mountain Bike Reviews Forum banner
61 - 80 of 81 Posts

·
squish is good
Joined
·
4,933 Posts
Black RONIN said:
Just one thought about the Cycling News report: regarding the 15QR being better or not than the regular QR, or a more efficient alternative for the current TA for lighter and stiffer forks, Fox IS a very influent company and WILL make it work anyway. Most companies are already adopting the 15QR in their new lineup of Trail and light AM bikes, so the trend is up and going. Mavic already realeased new models with both 15QR and 9mm, and DT have changed the front hub spec of their outstanding EX1750 to 15QR, leaving the 20mm version out of the picture, and now even CK is jumping right into it. Hardly it will become a dead standard from now on, with all these efforts to make it happen. Honestly, it seems like a good idea on paper, but if I had to choose from 15QR and TA, I'd seriously consider TA. If you wanna hard beating forks, then go with the strongest. The 15QR will probably replace the regular QR in 5 years, but won't cope with all the things a true 20mm axle can handle.
Most of those hubs you've listed are just 20mm hubs that have different spacers so they can do 15mm. There isn't much weight savings to be had at the hub in that case. And 5mm QR skewers sit inside of a 9mm housing that interfaces with the fork so I'm relatively certain the testing was done with the standard 9mm setup and not with a RWS system. I don't think any of us think this standard will go away on it's own. It only will if the market sees it for what it is. Heavier than 9mm QR and not significantly stiffer... I don't know how you see it but it seems silly to me.
 

·
wuss
Joined
·
2,380 Posts
Actually some companies seem to also be using a 9mm hub for this (same width). 20mm hubs would then be too wide and are not convertible (Mavic, maby Fulcrum).

I just don't understand why there is so little increase in stiffness. Most people seem to agrree a 12mm rear axle is way stiffer then a 10mm one, and a 10mm bolt on is stiffer then a QR. So how can we end up with a 15mm axle that so many (quality) companies adobt that gives so little benefit? Companies like DT and Marzocchi are even ditching 20mm axles on the shorter forks instead of keeping it as an option, you would think they would not do that lightly.

I would like to think that the test would not exactly reflect to real world tracking of the front end on a trail, but I guess it's still possible.
 

·
Registered
Joined
·
1,505 Posts
Clutchman83 said:
Most of those hubs you've listed are just 20mm hubs that have different spacers so they can do 15mm. There isn't much weight savings to be had at the hub in that case. And 5mm QR skewers sit inside of a 9mm housing that interfaces with the fork so I'm relatively certain the testing was done with the standard 9mm setup and not with a RWS system. I don't think any of us think this standard will go away on it's own. It only will if the market sees it for what it is. Heavier than 9mm QR and not significantly stiffer... I don't know how you see it but it seems silly to me.
When it first appeared, I thought it was the greatest thing. After a while, when I got to see it, I must admit it is very well made, very well thought as system and worth replacement for the 9mm QRs as it is meant to be - Fox and Shimano DO announces it as an evolution for the current QRs - but compared with the latest Maxle Lite, it is not as burly. You say the system is heavier, but the 09 15QR TALAS w/ the Axle weights about the same my 08 9mm QR TALAS. Considering that, the weight penalty is on the hub itself, but you don't count the skewer on that since it is attached to the fork, and for a standard hub, that's about 50g more with the skewer, so it's not about weight imo. The grip is in the standard itself. Until it becomes a major standard, replacing the current 9mm, it will be compared head to head with 20mm as the best TA, when in fact, the 15QR is what it is, a larger QR to add stiffness to the XC and trail background. It's not as good as the 20mm for heavy trail, AM or Freeriding. But mistakenly, it will be oftenly used by people who wish to set their rigs with the illusion that a bike can be both light as feather and strong enough to park riding. And seriously, that can't be done, yet.

So, for a replacement for the current QR, it is indeed a valid attempt. But it is not a alternative for 20mm and for bikes that demand real strenght and stiffness.
 

·
Registered
Joined
·
1,505 Posts
dropadrop said:
So how can we end up with a 15mm axle that so many (quality) companies adobt that gives so little benefit?
That's because it's not a Thru Axle, but still a Quick Release system. A TA "bolts" the hub and locks it, with no loss of strenght when you tight the lever. A quick release lever "releases" part of that lockout strenght when you push the lever close to the center of the wheel, loosing it a bit, what translates in loss of stifness. A DT RWS skewer has a higher stiffness ration compared to a regular QR because it has the same actuation as TA.

The 15QR system has a claimed 15% increase in stiffness, compared to 10% of a DT RWS TB. This difference becomes smaller if you consider a weight/stifness ratio taking in consideration the whole system (fork/hub/skewer).
 

·
squish is good
Joined
·
4,933 Posts
dropadrop said:
Actually some companies seem to also be using a 9mm hub for this (same width). 20mm hubs would then be too wide and are not convertible (Mavic, maby Fulcrum).

I just don't understand why there is so little increase in stiffness. Most people seem to agrree a 12mm rear axle is way stiffer then a 10mm one, and a 10mm bolt on is stiffer then a QR. So how can we end up with a 15mm axle that so many (quality) companies adobt that gives so little benefit? Companies like DT and Marzocchi are even ditching 20mm axles on the shorter forks instead of keeping it as an option, you would think they would not do that lightly.

I would like to think that the test would not exactly reflect to real world tracking of the front end on a trail, but I guess it's still possible.
Most 20mm hubs are actually narrower than 9mm hubs when you take the spacers off of them. And the factory can convert their own parts to do whatever they want. I'm not talking about conversion kits, I mean they simply took the 20mm hub and bearings and put 15mm diameter 100mm width spacers on them.

Regarding why they aren't as stiff, I'm really not certain since the 44's tested were actually engineered around a 20mm axle so there should be plenty of beef on the lowers. I suppose they could be making the axle out of really thin material to shave weight and it's allowing the fork to flex more. Personally I think the axle is kind of a strange place to try and shave weight, seems most would rather have one that's too strong than not strong enough.
 

·
wuss
Joined
·
2,380 Posts
Clutchman83 said:
Regarding why they aren't as stiff, I'm really not certain since the 44's tested were actually engineered around a 20mm axle so there should be plenty of beef on the lowers. I suppose they could be making the axle out of really thin material to shave weight and it's allowing the fork to flex more. Personally I think the axle is kind of a strange place to try and shave weight, seems most would rather have one that's too strong than not strong enough.
This is interesting. Maby someone will release a bulkier axle... :D
 

·
wuss
Joined
·
2,380 Posts
I was thinking about this yesterday and suddenly I figured out one possibility why Shimano has seen such an improvement in stiffness compared to the German magazines.

I would guess Shimano has had the hub included in the equation. I would also imagine they used their own hubs...

9mm M775 hub


15mm M778 hub


Maby the hub being double the thickness ends up adding more torsional stiffness then changing just the axle. The Germans could have tested using the same hub with adapters resulting in a result showing only the difference in stiffness due to the axle change.
 

·
squish is good
Joined
·
4,933 Posts
dropadrop said:
Maby the hub being double the thickness ends up adding more torsional stiffness then changing just the axle. The Germans could have tested using the same hub with adapters resulting in a result showing only the difference in stiffness due to the axle change.
Double the thickness would mean significantly heavier though right? You think they are going to bring a 15mm hub to market that is heavier than a 20mm hub? That would seem rather pointless to me.
 

·
wuss
Joined
·
2,380 Posts
There where more stiffness measurements from bike mag's different issues listed in this thread.

If we find that these measurements indeed show that the QR15 does not increase stiffness, we can make further conclusions too.

Fox QR9/15 torsional stiffness: 22.6/23.7
Fox QR9/15 braking stiffness: 177.2/180.3

Pike 454 Air / Coil U-Turn torsional stiffness: 22.6 / 24.1
Pike 454 Air / Coil U-Turn breaking stiffness: 178.0 /186.7

So going from air to coil on a pike does more to stiffness then going from 9mm to 15mm on a fox, but the air pike is less stiff then the qr15 fox?

Or then this is measuring only one quantity which does not mean absolute stiffness. ;)

edit: A 2007 issue of the mag also has the ratings for a Rock Shox Revelation 426 Air U-Turn (same issue actually has the Pike readings above)
torsional stiffness: 21.9
breaking stiffness:164.6

Which means that the difference in stiffness between a revelation quick release setup and a Pike Maxle (or Maxle 360, whatever they where shipping in summer 2007) is less then the difference between the QR9 and QR15 fox... :D
 

·
Registered
Joined
·
5,762 Posts
Was poking around searching for numbers - and it is interesting to see all the hand wringing around 15mm from about a year ago. Now that Rock Shox came out with 15mm across the under 160mm range and publicly stated that those would be the majority of their OEM sales.
Guess there was something to it.
 

·
Registered
Joined
·
6,087 Posts
Curmy said:
Was poking around searching for numbers - and it is interesting to see all the hand wringing around 15mm from about a year ago. Now that Rock Shox came out with 15mm across the under 160mm range and publicly stated that those would be the majority of their OEM sales.
Guess there was something to it.
Yes but it does not change the fact that 15mm is not as good as 20m and only a little better than a QR. The 15mm is more about hype than function.
 

·
Registered
Joined
·
406 Posts
Weather 15mm is stiffer or not is besides the point for me. I'm getting a new bike within the next week and there is a decent chance it will have a 15mm axle on it. I would take any thru axle fork over QR for peace of mind knowing the axle is going through both dropouts. While breaking a QR skewer may be rare, it doesnt make me feel good knowing that if the skewer breaks, my front wheel is going to leave the bike.
 

·
The MTB Lab
Joined
·
2,556 Posts
An old thread from the multiply banned Jerk Chicken!

The number comparison reminds me of audiophile gear. Is the output, both quantitative and especially qualitative of a Mark Levinson 100 watt amplifier the same as a Pioneer 100 watt amp?

I think any human can easily feel the stiffness between a QR and a 15mm thru axle on a fork on a rocky and rough trail. The difference between a 15mm and 20mm is a bit more fine toothed of a feel, but it is discernible, albeit maybe not by everyone. No matter what the machinery records as output for analysis, the perceptions of a rider are pretty darn amazing and accurate. There are a huge amount of variables that occur on a trail, between the rider, the bike frame, the fork, the tires and the terrain, etc.

QR's were invented on a road bike, and belong there, not on a mountain bike that is subjected to enormous impacts, abuse and general torture that a QR system was never designed for. Sure a QR will work, but if you started from scratch it would never have been the standard.
 

·
Registered
Joined
·
5,762 Posts
pastajet said:
I think any human can easily feel the stiffness between a QR and a 15mm thru axle on a fork on a rocky and rough trail. The difference between a 15mm and 20mm is a bit more fine toothed of a feel, but it is discernible, albeit maybe not by everyone. No matter what the machinery records as output for analysis, the perceptions of a rider are pretty darn amazing and accurate. There are a huge amount of variables that occur on a trail, between the rider, the bike frame, the fork, the tires and the terrain, etc.
An interesting and very immediate question for me (and the reason I was poking around old discussions) is what would be stiffer - a Fox lowers tied with 15QR, or noticeably stiffer Magura lowers with 9mm Hadley through bolt (not a QR) - on the same Hope hub.
 

·
mbtr member
Joined
·
6,503 Posts
Curmy said:
An interesting and very immediate question for me (and the reason I was poking around old discussions) is what would be stiffer - a Fox lowers tied with 15QR, or noticeably stiffer Magura lowers with 9mm Hadley through bolt (not a QR) - on the same Hope hub.
I couldn't tell you that, but i can tell you similar experience and you can extrapolate...

I had a 130qr rev. It was annoyingly squirmy. I've spent a fair bit of time on a float 140qr. It was annoyingly squirmy. I put a 9mm through bolt (skraxle hub) on my rev, and the flex no longer distracted me; which is how i would also describe the qr15 floats i've demo'ed- i didn't really notice any difference in stiffness, just damping. Stepping up to a pike was a real leap in stiffness though; my confidence increased markedly on the same bike.

I infer that they would be about the same.
 

·
wuss
Joined
·
2,380 Posts
The problem is, that axle is just a part of the equation. I found the Pike to be flexy compared to a Wotan despite both having a maxle.

Given the lack of actual data from manufacturers, I wonder if they had to sign an NDA not to go into it?

Any measurements from Germany between EXC150's with 20 and 15mm axles? How about them going further in depth on their testing methodology (since it did not seem like the where measuring the same thing people here were talking about)?
 

·
Registered
Joined
·
10 Posts
Reviving a one year old thread might not be a smart idea but I found it useful and was definitely the switch in my decision.

I am on the point to upgrade my fork and move it from an old coil Tora to a Brand New Reba RLT 2012.
After reading all 78 posts from head to tail ( idk where so much patience) I can say that this thread saved my ass from spending like $300+ representing the 15mm option for Reba(like $100+) and a new front wheel with 15mm bolt-on hub.

From some reasons beyond my knowledge, RS didn't released the 15mm axle for RL, making it available only for RLT one which is only marketing. For that T which is pointless for me you have to pay $50 more and another $30 to reach the 15mm axle which is stupid.

I know things evolved since 2009, more or less but the long debate makes me stay on the current QR9 and give up the option with 15mm thru-axle.
Before reading this I was 100% sure it will worth the investment and will totally make the difference but I changed my mind considering I won't go into the AM side and stay more on 120mm travel XC with this bike.
 

·
Dual Squishy...
Joined
·
650 Posts
Yup, read this and realized the same thing. Was planning on swapping the lowers on my SID to 15mm lowers and building out a front wheel based on a Hope Pro II EVO 15mm hub.

Now I think I will just go with the 9mm through axle and keep my existing lowers and build up said wheel above with 9mm spacers. Saving me about $250 + labor... WooT!
 
61 - 80 of 81 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top