View Full Version : Is 1.5 the new 1 1/8th
e30 guy
15-11-2006, 06:16 PM
Why has there been this move from the 1 1/8th" head tube diametre to 1.5" :confused: Is it purely strength related?
I think that it is stronger and gives it a lower stack height.
sam.
http://www.onepointfivestandard.com/ says this
The onepointfive standard for bicycle fork steerers, headsets, stems, and frames is what makes lightweight, long travel, singlecrown freeride bikes possible.
onepointfive is not about egos or marketing spin; it is about sound technology leading to marked strength, stiffness, and weight improvements. As a result, all technical information and drawings contained herein are freely shared with all interested parties.
both Manitou and Rock Shox have published figures that say it provides significant stiffness increase and is slightly lighter.
e30 guy
15-11-2006, 06:54 PM
Does the bigger diametre of the steerer tube mean a thinner wall can be used? Because otherwise wouldnt it be heavier?
Does the bigger diametre of the steerer tube mean a thinner wall can be used? Because otherwise wouldnt it be heavier?
Yeap. Look up "polar moment of inertia" and you'll understand why it's so much more useful.
As far as headtubes go though, it's just a clear-cut winner. You can run large bearings in a removable internal headset which means low stack height but longer headtube, which combined with the fact that the headtube is also wider, means that you have a MUCH stronger headtube interface than 1 1/8th can offer.
Does the bigger diametre of the steerer tube mean a thinner wall can be used? Because otherwise wouldnt it be heavier?
typically the use alloy for 1.5 and steel for 1 1/8
Turner_rider
16-11-2006, 11:05 AM
In some respects 1.5 is the new 1 1/4"..... ;)
In some respects 1.5 is the new 1 1/4"..... ;)
1 1/4 was short sighted
The US mba keeps calling the 1.5" the new "standard". But in the same mag they published comments by Dave Turner and Marzocchi that they would both sit back awhile and see where it goes before committing to a retooling program to suit the next new "fad". That was a couple of years ago now however so I dont know whether their feelings would be the same now.I'd reckon if the manufacturers wanted in then they would offer the 1.5 as factory built with a set of reducers or a custom headset to reduce to 1.125 if the customer required.....
:confused:
cheers jon
Dicky
16-11-2006, 07:56 PM
Too many kids snapping their headtubes off while JRA... :p
Giantrider
16-11-2006, 08:21 PM
the guys at my lbs said its just another mtb idea one of many before that... theres not much difference in strenght 'apparently' and it is just a different ride
Turner_rider
17-11-2006, 09:39 AM
1 1/4 was short sighted
Maybe but I recall similar debate to the current 1.5 at the time.
Maybe but I recall similar debate to the current 1.5 at the time.
I wasn't arround for the 1.25 debate but I was for the Long travel single crown debate which was sparked off by the same product as the 1.5 debate; the 2003 sherman breakout.
It seems to be the mechanical/materials engineers who design and test these products vs the US hype magazines and a plethora of stuck in their ways mechanics.
If you look at the european magazines, particulariy the german ones they actually test things in engineering labs and publish facts as well as oppinions.
Anyone who's worked in a shop over the last two years can probably attest to the frequency with which teenagers are bending the extra thich steel steerers in Marzocchi forks.
and it hasn't been mentioned yet, but 1.5 headsets, even the cheap ones, seem to last forever.
the guys at my lbs said its just another mtb idea one of many before that... theres not much difference in strenght 'apparently' and it is just a different ride
ask a mechanical or structural engineer (S maybe) for a second oppinion, they might be great mechanics but I doublt they have expertiese in engineering.
ovadahill
17-11-2006, 02:43 PM
Good reliable anecdotes does not equal data.
Good reliable anecdotes does not equal data.
you don't have to look that hard to find it,
Designs are possible that are 44% stronger and 138% stiffer for similar weight of 1 1/8". 1.5 system allows for lightweight single crown forks with 170mm of travel.http://www.answerproducts.com/popup-tech.asp?techid=7
The Totem OnePointFive is a seriously stiff fork, even moreso than the 1 1/8" version. It's 20% stiffer under bending loads, and 10% under torsional loads than its less-girthy brother. It's also 90g lighter.http://www.nsmb.com/gear/rockshox07_06_06.php
Hell has frozen over. I was gobsmacked when I heard that Marzocchi is producing a 1.5" steerer model 66 for 2007. Bryson Martin, president and CEO of Marzocchi USA, was extremely vocal in his opposition to this new standard when Manitou brought it to market but demand from frame manufacturers was such that they were left with little choice. In their own words 'we thought it would never happen.' The beer can-sized head tube allows designers to beef up the front end of their bikes due to a larger contact area between the headtube/toptube and seat tube. The big stick 66 won't be available in your LBS though - unless it's already attached to a bike. http://www.nsmb.com/gear/marz07_06_06.php
AndyDrew
17-11-2006, 07:42 PM
pwned!
I hate that word so much.
pistonbroke
17-11-2006, 11:27 PM
Hi guys,
I'm new to mtb's.
My cannondale has a 1.5(correct me if I'm wrong).It's a jekyll 1000 with a lefty fork.
My question is,will ANY 1.5 stem fit this bike or are the cannondales differant to other bikes?
Hi guys,
I'm new to mtb's.
My cannondale has a 1.5(correct me if I'm wrong).It's a jekyll 1000 with a lefty fork.
My question is,will ANY 1.5 stem fit this bike or are the cannondales differant to other bikes?
Will it fit a Cannondale?
All Cannondale freeride bikes are designed to be fully compatible with the new OnePointFive system including the Lefty platform (as of the 2003 model year) . For more information on the compatibility of Cannondale and OnepointFive please go to www.Cannondale.com/bikes/tech/onepointfive (http://www.cannondale.com/bikes/tech/onepointfive). *edit; the link dosen't work... sorry
if it meets the 1.5 standard then a 1.5 stem should fit.
ovadahill
18-11-2006, 11:36 AM
Good reliable anecdotes does not equal data.
you don't have to look that hard to find it,
http://www.answerproducts.com/popup-tech.asp?techid=7
http://www.nsmb.com/gear/rockshox07_06_06.php
http://www.nsmb.com/gear/marz07_06_06.php
It's interesting how you interpret marketing exerpts as "data". The quoted references are regurgitated figures from the fork manufacturing companies media releases.
I actually believe that 1.5 is stronger - mainly because it allows a larger bearing interface where side loading is an important factor. No doubt the fork and frame companies have their own tests that show some performance or strength benefit. I think that in order for those results to be accepted scientifically the data needs to be derived from independent sources. I'm sure the information exists somewhere in a university archive from an engineering student's thesis. Can someone enlighten us.
It's interesting how you interpret marketing exerpts as "data". The quoted references are regurgitated figures from the fork manufacturing companies media releases.
I actually believe that 1.5 is stronger - mainly because it allows a larger bearing interface where side loading is an important factor. No doubt the fork and frame companies have their own tests that show some performance or strength benefit. I think that in order for those results to be accepted scientifically the data needs to be derived from independent sources. I'm sure the information exists somewhere in a university archive from an engineering student's thesis. Can someone enlighten us.
the percentages are comparisons between the 1 1/8 and 1.5 versions of a given product by it's manufacturer, why would they need to lie about it?
Anyway, how come your playing devils advocate when you agree with me?
I think another big advantage is the increase in contact area between the steerer and the crown.
T-Bone
18-11-2006, 02:30 PM
I have a FSA Fat Pig on my ride. Its 1.5 and its is a very strong and light setup. Apparently it is stonger in comparision to the 1 1/8th.
I thought it was because I have a Cannondale and its to accomodate the "lefty" fork.
Turner_rider
18-11-2006, 11:08 PM
It seems to be the mechanical/materials engineers who design and test these products vs the US hype magazines and a plethora of stuck in their ways mechanics.
If you look at the european magazines, particulariy the german ones they actually test things in engineering labs and publish facts as well as oppinions.
Anyone who's worked in a shop over the last two years can probably attest to the frequency with which teenagers are bending the extra thich steel steerers in Marzocchi forks.
ask a mechanical or structural engineer (S maybe) for a second oppinion, they might be great mechanics but I doublt they have expertiese in engineering.
I'm not doubting the engineering behind 1.5 - am engineer myself and can do the math ;)
But how much strength is required here? is 1.5 potentially overkill?? (devils advocate Qs)
I agree that there are riders bending steerers, but there are also a lot breaking the fork internals, arches and more commonly arms, legs, ankles and wrists. So maybe a bent steerer as a failure mode to save your body is potentially a good thing.
The bean counters will also need a lot of convincing before before putting extra money it making products for what is still a niche market, but they can argue their case... ;)
But how much strength is required here? is 1.5 potentially overkill?? (devils advocate Qs)
it seems to me that within 10 years of moving from 1 to 1 1/8, 1 1/8 was being pushed to it's limmits, hence my comment about 1 1/4 being short sighted.
1.5 should have a substantialy longer life span before we need to go bigger again.
the Cannondale i baught over 10 years ago was 1 1/4. And that was with a rigid fork. 1 1/4 wasnt short sighted at all. It was just miles ahead of time.
I'm not doubting the engineering behind 1.5 - am engineer myself and can do the math ;)
But how much strength is required here? is 1.5 potentially overkill?? (devils advocate Qs)
I agree that there are riders bending steerers, but there are also a lot breaking the fork internals, arches and more commonly arms, legs, ankles and wrists. So maybe a bent steerer as a failure mode to save your body is potentially a good thing.
The bean counters will also need a lot of convincing before before putting extra money it making products for what is still a niche market, but they can argue their case... ;)
Well clearly it's not overkill, as bent steerers (with SC forks) are hardly uncommon (even those nearly solid steel poles Marzocchi install in their dirtjump forks) on 1.125 forks, yet nobody seems to be doing it with 1.5. That and the fact that it's also not super uncommon to ovalise headsets/headtubes with 1.125 yet rarely seems to happen, should be enough of a reason for anyone. But just in case you're still not convinced: there are a LOT of broken frames at the junction of 1.125 headtubes, but other than the SGS that a certain N Rennie decided to huck to front wheel from like 10ft up in a race run, I haven't actually seen a destroyed 1.5 headtube YET. I'm sure it's been done, but it's obviously far far less common. And that's a good thing.
Oh yeah and lower stack heights, bigger bearings etc etc... win. Why any frame manufacturer of aggressive-use bikes would NOT spec a 1.5 headtube is frankly beyond me.
the Cannondale i baught over 10 years ago was 1 1/4. And that was with a rigid fork. 1 1/4 wasnt short sighted at all. It was just miles ahead of time.
1.25 was short sighted in that:
a) it wasn't backwards compatible (not big enough to fit an internal set of bearings in like 1.5)
b) it wasn't significantly bigger than 1.125 (whereas 1.5 is a much bigger jump), which meant that it was never going to achieve significantly more strength and thus have a significantly longer lifetime.
alpinestar12
21-11-2006, 10:42 PM
I bent my marzocchi 1 1/8th steerer. Didn't think I rode it hard enough that it should do that, but anyways...
I think frame manufacturers should build 1.5 frames even if they don't put 1.5 forks in them. way stronger headtube, more weld surface area, can use big bearings with low stack height too. more stifness.
disadvantages? maybe a tiny bit more weight? marzocchi don't make AM 1.5 forks? I reckon they'll come over to the dark, or smart, side soon enough.
alpinestar12
21-11-2006, 10:47 PM
just gotta say that talking about inches in decimal points instead of fractions is stupid. rant over.
kizza01
21-11-2006, 10:52 PM
just gotta say that talking about inches in decimal points instead of fractions is stupid. rant over.
Hahaha thats gold, i never thought of it!
How come we still use inches and feet anyway, its pretty confusing.
Hahaha thats gold, i never thought of it!
How come we still use inches and feet anyway, its pretty confusing.
Does it really matter?
We use a few measurements of power too - KW's, HP, etc.
Inches and feet, centimeters and meters are pretty easy to comprehend - 12 inches in a foot, 100cm's in a meter... thats about as complex as it gets!
Anyway back onto headtubes:)
I haven't actually seen a destroyed 1.5 headtube YET.
I've seen two woodman D's with a crack under the heastube/downtube junction but that particular frame is alloy and 600g lighter than most frames in it's class.
anyway that's the exception really not the rule.
alpinestar12
21-11-2006, 11:49 PM
Hahaha thats gold, i never thought of it!
How come we still use inches and feet anyway, its pretty confusing.
cause we're idiots. especially americans.
I'm all for more use of the 38.1 mm headtube standard.
just gotta say that talking about inches in decimal points instead of fractions is stupid. rant over.
hahahaha, not my fault if it takes you that long to work out that 0.125 = 1/8th. Besides, the next increment down from inches in the imperial system is thousandths... perfectly fine for use with decimals. I'd agree if we were using something like 19/32nds or whatever, but we're not, so suck it up.
alpinestar12
23-11-2006, 09:48 PM
No I won't goddamn suck it up. The imperial system should have started dying the moment that smart french guy or whoever thought it up, and it should be well and truly dead by now.
that smart French Dude was King Louis XVI and according to wikipedia the only stronghold for the imperial system is that big red blob on the left.
http://forums.farkin.net/attachment.php?attachmentid=52095 (http://upload.wikimedia.org/wikipedia/en/1/17/Metric_system.png)
scratchy
24-11-2006, 08:59 AM
To chuck my 2 cents in. Why wouldn't you? On the frame aspect alone you are allowing a larger weld contact over a larger area (reducing chances of hotspots, which weaken the frame). Forks bend, pffft. But if you toast a frame...
On the flipside aren't Motobikes 1 1/8th?
If it can be made lighter and stronger then it should cross over into XC. The only issue with that is some XC has gone a little conservative.
Mountain Bikes were invented by a bunch of free thinkers on Paperboys. Considering that you can reverse it (run a 1 1/8th steerer in a 1.5 headtube) it seems like a good idea to me.
Until accredited by the introduction of a Chris King Headset to suit (not reduce), it's mearly a fad.
I believe it will happen.
nizai
24-11-2006, 02:59 PM
Doesnt the 1.5" "fad" help facilitate manufacturers to produce single crown free ride forks?
N
tnankie
24-11-2006, 04:49 PM
The US mba keeps calling the 1.5" the new "standard". But in the same mag they published comments by Dave Turner and Marzocchi that they would both sit back awhile and see where it goes before committing to a retooling program to suit the next new "fad". That was a couple of years ago now however so I dont know whether their feelings would be the same now.I'd reckon if the manufacturers wanted in then they would offer the 1.5 as factory built with a set of reducers or a custom headset to reduce to 1.125 if the customer required.....
:confused:
cheers jon
The big M now make OEM 1.5s, no retail versions yet old news soz
bring on the 40mm headset/steerer
To chuck my 2 cents in. Why wouldn't you? On the frame aspect alone you are allowing a larger weld contact over a larger area (reducing chances of hotspots, which weaken the frame). Forks bend, pffft. But if you toast a frame...
On the flipside aren't Motobikes 1 1/8th?
If it can be made lighter and stronger then it should cross over into XC. The only issue with that is some XC has gone a little conservative.
Mountain Bikes were invented by a bunch of free thinkers on Paperboys. Considering that you can reverse it (run a 1 1/8th steerer in a 1.5 headtube) it seems like a good idea to me.
Motorbikes are 1" I believe, but they use massive tapered roller bearings to begin with (thus the head tube is fairly large), and for dual crown forks there isn't much bending stress on the steerer anyway. Some of the Avalanche forks don't even have a steerer tube, just a pair of stubs above and below the bottom and top crowns, respectively, and a threaded rod (like a Headlock) to preload the headset bearings. Either way, not much point comparing motos to mtbs.
toodles
27-11-2006, 07:50 PM
Until accredited by the introduction of a Chris King Headset to suit (not reduce), it's mearly a fad.
I believe it will happen.
As soon as King bring their over-priced, over-hyped shit to the 21st century you'll accept it? Fair call. I'm not buying a TV till the Amish design a plasma screen either...
ovadahill
27-11-2006, 08:14 PM
As soon as King bring their over-priced, over-hyped shit to the 21st century you'll accept it? Fair call. I'm not buying a TV till the Amish design a plasma screen either...
Chris King povide a strong, well thought out argument against integrated headsets (and comments on internal headsets) on their tech page (http://www.chrisking.com/tech/int_headsets_explained/int_hds_explain_1.html). It adds a balance to the 1 1/8 v. 1 1/2 discussion.
(I'm not arguing the issue about the price or hype).
alpinestar12
27-11-2006, 08:28 PM
Some of the Avalanche forks don't even have a steerer tube, just a pair of stubs above and below the bottom and top crowns, respectively, and a threaded rod (like a Headlock) to preload the headset bearings.
Maverick dual crowns use this too I believe.
toodles
27-11-2006, 08:52 PM
Chris King povide a strong, well thought out argument against integrated headsets (and comments on internal headsets) on their tech page (http://www.chrisking.com/tech/int_headsets_explained/int_hds_explain_1.html). It adds a balance to the 1 1/8 v. 1 1/2 discussion.
They have nothing to say against 1.5" headsets... I have a great respect for the king company and their ethos, but I'm bewildered as to why they haven't catered to the 1.5" market.
Plow King
27-11-2006, 09:13 PM
yes
.....................
ovadahill
27-11-2006, 09:43 PM
I thought most of the 1.5 headsets were integrated or internal --- but I was wrong: "The One-Point-Five standard does not address head tubes for integrated type systems. Integrated style headsets are not appropriate for the market segment targeted by the One-Point-Five System. Integrated type headsets leave the head tube vulnerable to damage, since they lack a bearing cup that resides between the bearings and the frame. While they may be appropriate for the road bicycle segment, they are not appropriate for the Freeride and Downhill segments."....onepointfivestandard.com
I suppose that shreds my argument.
Until accredited by the introduction of a Chris King Headset to suit (not reduce), it's mearly a fad.
I believe it will happen.
King were part of the orignal consortium that developed the standard
December 19, 2001 -- Race Face Performance Products, King Cycle Group, Rocky Mountain Bicycles, Cane Creek Components and Answer/Manitou announce today the introduction of a new interface standard for bicycle front-end frame components.
ovadahill
27-11-2006, 11:32 PM
King must have backed out because: a.) they found flaws in the idea, b.) they got payed out by the other headset companies to give them a piece of the action, or c.) they projected that the profits from the new 1.5 standard weren't substantial enough to warrant new dies and tools in their production line.
I'd like to believe it was a.)
toodles
28-11-2006, 06:29 AM
King must have backed out because: a.) they found flaws in the idea, b.) they got payed out by the other headset companies to give them a piece of the action, or c.) they projected that the profits from the new 1.5 standard weren't substantial enough to warrant new dies and tools in their production line.
I'd like to believe it was a.)
More likely they're waiting to clear stock of 5,000 uber expensive headsets hand crafted by tibetian virgin monks
No Skid Marks
28-11-2006, 09:46 AM
or King are holding back because they got stung on the 1 1/4 size when Aheadset(unfortunately)smashed them with 1 1/8th.
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