How about manufacturers focus on real improvements?

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How about manufacturers focus on real improvements?
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flag maetpad
Posted: Feb 25, 2018 at 18:51 Quote
So, I have been wondering: why are manufacturers giving us 29.8mm bottom bracket Bull S , when there is an obvious area which they have not looked at : stem to fork connection...

It seems to me that cycling is the only sport where the alignment of the wheel and the bar ( ie the connection to the pilot / rider) is done visually.
for bike: all dual crown
for cars: laser alignment machines.

in other words, and keeping dual crown DH forks aside, how do you know that your wheel and your bar are perfectly aligned?
there are not markings, let alone grooves or ingots to position stem and steerer... The more I think about it the more I find this completely primitive...

Best,

Matt
flag gotohe11carolina
FL
Posted: Feb 25, 2018 at 20:12 Quote
So a very simple and cheap solution would be for fork manufacturers to put a line in the back of the steerer tube. Then you just put the line in the split on your strm and voila, all of us anal retentive bikers get a perfectly aligned stem.
flag OnionRing
Posted: Feb 25, 2018 at 20:35 Quote
maetpad wrote:
So, I have been wondering: why are manufacturers giving us 29.8mm bottom bracket Bull S , when there is an obvious area which they have not looked at : stem to fork connection...

It seems to me that cycling is the only sport where the alignment of the wheel and the bar ( ie the connection to the pilot / rider) is done visually.
for bike: all dual crown
for cars: laser alignment machines.

in other words, and keeping dual crown DH forks aside, how do you know that your wheel and your bar are perfectly aligned?
there are not markings, let alone grooves or ingots to position stem and steerer... The more I think about it the more I find this completely primitive...

Best,

Matt

photo

The RED item represents a long straight thing. e.g - a straight edge.

The YELLOW indicators are for eyes only.


Or, you could do your things with the money and time, yeah - I say go for it.
flag Hammer48
Posted: Feb 25, 2018 at 20:56 Quote
Buy a cheap laser, center it on your stem, then line up the center of your tire to the laser..bam..done deal..Big Grin
flag sdaly
O+
Posted: Feb 26, 2018 at 5:36 Quote
Maybe you should try another sport...like knitting
flag RunsWithScissors
Posted: Feb 28, 2018 at 9:36 Quote
One great reason for not having a keyed connection between the steerer tube and stem is crash survivability. If you have a keyed interface that can't slip under impact then you increase the risk of breaking handlebars and/or bones instead.

A keyed interface also creates the possibility of alignment issues being "baked in" during manufacturing, i.e someone at the factory screws up a machine setting by say, a degree or two and then maybe nobody notices until they've made a shipping container full of stems and sent them out into the wild. Now you have a quality control issue to deal with that you never would have had if you'd left well enough alone and not reinvented that interface.

Add in the fact that most manufacturers aren't crazy about universal "standards" and you'll have Shimano making a square steerer, SRAM making a triangular steerer, and DVO deciding to go with splines, and now the customer has one more way to order the wrong part and then complain about new "standards" being forced upon them by a greedy and uncaring industry.

From a manufacturer's perspective there's just little or no payoff to keyed interfaces between steerer and stem.
flag cerebroside
O+
Posted: Feb 28, 2018 at 11:08 Quote
RunsWithScissors wrote:
One great reason for not having a keyed connection between the steerer tube and stem is crash survivability. If you have a keyed interface that can't slip under impact then you increase the risk of breaking handlebars and/or bones instead.

A keyed interface also creates the possibility of alignment issues being "baked in" during manufacturing, i.e someone at the factory screws up a machine setting by say, a degree or two and then maybe nobody notices until they've made a shipping container full of stems and sent them out into the wild. Now you have a quality control issue to deal with that you never would have had if you'd left well enough alone and not reinvented that interface.

Add in the fact that most manufacturers aren't crazy about universal "standards" and you'll have Shimano making a square steerer, SRAM making a triangular steerer, and DVO deciding to go with splines, and now the customer has one more way to order the wrong part and then complain about new "standards" being forced upon them by a greedy and uncaring industry.

From a manufacturer's perspective there's just little or no payoff to keyed interfaces between steerer and stem.

Seems like if this was all such a big problem then direct mount stems wouldn't be a thing?

I think getting the bars straight is one of the most annoying parts of setting my bikes up, so I'm all for indexed steerers.
flag a-d-e
O+
Posted: Feb 28, 2018 at 11:53 Quote
cerebroside wrote:
RunsWithScissors wrote:
One great reason for not having a keyed connection between the steerer tube and stem is crash survivability. If you have a keyed interface that can't slip under impact then you increase the risk of breaking handlebars and/or bones instead.

A keyed interface also creates the possibility of alignment issues being "baked in" during manufacturing, i.e someone at the factory screws up a machine setting by say, a degree or two and then maybe nobody notices until they've made a shipping container full of stems and sent them out into the wild. Now you have a quality control issue to deal with that you never would have had if you'd left well enough alone and not reinvented that interface.

Add in the fact that most manufacturers aren't crazy about universal "standards" and you'll have Shimano making a square steerer, SRAM making a triangular steerer, and DVO deciding to go with splines, and now the customer has one more way to order the wrong part and then complain about new "standards" being forced upon them by a greedy and uncaring industry.

From a manufacturer's perspective there's just little or no payoff to keyed interfaces between steerer and stem.

Seems like if this was all such a big problem then direct mount stems wouldn't be a thing?

I think getting the bars straight is one of the most annoying parts of setting my bikes up, so I'm all for indexed steerers.
the problem is that the steerer is only 1 1/8in with the bars being close to 800mm. any imperfection at the interface massively amplified at the bar tips. both stem & fork manufacturers would need to co op. can you really see fox offering both keyed & non-keyed forks in the line-up? machining tolerances would need to be extremely precise to costs would be huge. direct mount stem interface is almost 3 times the size at the stem plus it also interface with the actual stanchion.
all this to reduce the effort of setting up handlebar position. it does not solve a 'problem' as 99.9% of people probably can get close enough that they are satisfied. lets face it the trails certainly aint straight & I do not look at my cockpit EVER when im riding. yes I like to get my bars as close to centred/straight as possible when setting up my bike but many times ive ridden with wonky bars after a crash & only come to realise weeks later they are pissed as f**k Confused
flag cerebroside
O+
Posted: Feb 28, 2018 at 13:12 Quote
a-d-e wrote:
the problem is that the steerer is only 1 1/8in with the bars being close to 800mm. any imperfection at the interface massively amplified at the bar tips. both stem & fork manufacturers would need to co op. can you really see fox offering both keyed & non-keyed forks in the line-up? machining tolerances would need to be extremely precise to costs would be huge. direct mount stem interface is almost 3 times the size at the stem plus it also interface with the actual stanchion.
all this to reduce the effort of setting up handlebar position. it does not solve a 'problem' as 99.9% of people probably can get close enough that they are satisfied. lets face it the trails certainly aint straight & I do not look at my cockpit EVER when im riding. yes I like to get my bars as close to centred/straight as possible when setting up my bike but many times ive ridden with wonky bars after a crash & only come to realise weeks later they are pissed as f**k Confused

No different from machining the bar clamp bore. How often are do you notice those being crooked?

As much as people joke about stuff like '28.99', the machining tolerances for bike parts are pretty tight. I feel like machining a keyed steerer would be fairly easy compared to fork internals.

Is it worth creating another standard? Who knows. Worth more to me personally than useless stuff like Boost.

EDIT: Looks like the accuracy of cheap rotary tables is in the range of 10 arc seconds (~0.003 degrees). I don't know enough to say how this sort of thing would be machined, but I don't think getting it centered accurately would be a problem.
flag Davec85
FL
Posted: Mar 4, 2018 at 4:25 Quote
Don't see it as a big deal personally. Cars have laster alignment to ensure both wheels are perfectly aligned thus preventing crabbing and uneven tyre wear. Don't see a need for more complexity and another stabdard, it can be aligned to within a degree or two by eye.
flag a-d-e
O+
Posted: Mar 4, 2018 at 7:00 Quote
cerebroside wrote:
a-d-e wrote:
the problem is that the steerer is only 1 1/8in with the bars being close to 800mm. any imperfection at the interface massively amplified at the bar tips. both stem & fork manufacturers would need to co op. can you really see fox offering both keyed & non-keyed forks in the line-up? machining tolerances would need to be extremely precise to costs would be huge. direct mount stem interface is almost 3 times the size at the stem plus it also interface with the actual stanchion.
all this to reduce the effort of setting up handlebar position. it does not solve a 'problem' as 99.9% of people probably can get close enough that they are satisfied. lets face it the trails certainly aint straight & I do not look at my cockpit EVER when im riding. yes I like to get my bars as close to centred/straight as possible when setting up my bike but many times ive ridden with wonky bars after a crash & only come to realise weeks later they are pissed as f**k Confused

No different from machining the bar clamp bore. How often are do you notice those being crooked?

As much as people joke about stuff like '28.99', the machining tolerances for bike parts are pretty tight. I feel like machining a keyed steerer would be fairly easy compared to fork internals.

Is it worth creating another standard? Who knows. Worth more to me personally than useless stuff like Boost.

EDIT: Looks like the accuracy of cheap rotary tables is in the range of 10 arc seconds (~0.003 degrees). I don't know enough to say how this sort of thing would be machined, but I don't think getting it centered accurately would be a problem.
c'mon guy is it really that difficult to put a stem on straight? you should try doing it with a 38mm track bar with no not a straight edge on it - less easy to eye-it-through than a 780mm riser bar thats practically straight but still can get it close enough that it feels centred & straight.
yes IT IS POSSIBLE to machine a keyed steerer interface to close tolerances but aligning the front axle on the lowers to the steerer key is one element then machining the stem accurately & with a system that has ZERO PLAY as even the smallest amount of play would render the whole thing pointless.
then the task of getting manufacturers to co op? likely not but maybe dvo or fox would make a stem/fork system? doubt they will as it seems a massive cost for R&D probably looking at silly money to fund what you think 50,000? 100,000? (i have no idea) you be paying someone for months/years to manage project plus all the cad design machining advertising & promotion all those costs add up & all for what?? so you can fit the handlebar straighter than the human eye can detect?? lol lol
heres an idea off the top of my head that would help fit bars straight:
lets call it an 'alignment axle' which is basically a standard axle that has say (for practicality & costs) 200mm either side sticking out to aid eyeing through the bars whilst you tighten up the stem. maybe you can get a local machine shop to knock one up?
flag a-d-e
O+
Posted: Mar 4, 2018 at 7:06 Quote
Davec85 wrote:
Don't see it as a big deal personally. Cars have laster alignment to ensure both wheels are perfectly aligned thus preventing crabbing and uneven tyre wear. Don't see a need for more complexity and another stabdard, it can be aligned to within a degree or two by eye.
1 degree on an 800mm bar would be 4.5mm at the tip. thats one grip 9mm in front of the other (yes think about it!!!) id bet most people can get to within a degree easily.
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