[Closed] Bike standards that perplexingly haven't changed

Specific pedal-cranks standards have been tried and they died a death, no-one was willing to take the risk as there was no backwards compatibility like most new standards have (with adaptors etc.).

[img] [/img]

These are the only one I can think of. I guess I'm just suprised no-ones tried to resurrect some sort of variation recently.

Cranks come in 1 standard size.

ok, that's not [i]strictly[/i] true, buy have you tried buying anything other than 170 +/- 3% ?

it's even more impossible to find anything that'll fit a new press-fit frame.

in a world where we can buy frames from 14" to 22" (and more), and stems from 30mm, to 150mm (and more), bars in widths from teeny tiny, to a full yard. Cranks vary by 6%. That's less than the difference between an 18" frame, and a 19" frame.

and then we get told to pay for bike-fitting, when one of the most important components can't be altered!

(+/- 3%? that's little more than machining error)

Q: what innovation does my 5foot wife require from shimano?

A: 140mm cranks, so she can perform the miracle of pedaling without kneeing herself in the face.

Q: what does she get offered instead?

A: 11 speed! - because that'll help a heap.

FFS.

Boardman in RCUK was mentioning that pro riders should be switching to 150mm cranks

https://roadcyclinguk.com/gear/chris-boardmans-seven-tech-trends-2016.html#iW2I81KDuzzQ1Pa9.97

ok, that's not strictly true, buy have you tried buying anything other than 170 +/- 3% ?

yes, it's quite easy.

Indeed, a search for "150mm bicycle cranks" turns up lots of hits including some from a firm I've never heard of called Shimano from some obscure outfit called Chainreaction Cycles.

Wheels that aren't circular.

jekkyl - Member
Wheels that aren't circular

Well 29" wheels are more round than 27.5, and since 29" wheels are undeniably just round not extra round or anything, then a 26" wheel (which is less round than something which is less round than something which is round) must be not round :. 20" wheels must be nearly square and you can get those, in fact they put the on kids bikes to get 'em hooked young because they're less sceptical than adults.

Laterally round and horizontally pentagonal

GregMay - Member

yes, it's quite easy.

humour me?

whitestone - Member
...from some obscure outfit called Chainreaction Cycles.

i can only find a link to some 105 roadie cranks...?

http://www.sjscycles.co.uk/thorn-110-74-pcd-triple-solo-alloy-crankset-silver-prod1673/

SJS are great. OK they're not latest greatest offset-BCD BB30 spec but that's no bad thing.

You didn't mention anything about being fussy! 😀

The problem of course with running very short cranks is your seat height is higher (presuming xc/road riding obv) so reaching the ground is near impossible. Ive seen people solve this by smaller wheel size, to bring the pedal-ground distance back to what it was with the designed cranks.

finbar - Member

These are the only one I can think of. I guess I'm just suprised no-ones tried to resurrect some sort of variation recently.

In line with the op though.

Why oh why does no one do split clamps on shifters? It works fine for brakes why not a damn gear lever. Why do I have to remove everything from my bar to remove the shifter?

@ ahwiles - I get your point but don't kid yourself that 3% is any kind of machining tolerance far from it! I often worked to +-0.1 mm as an absolute maximum and believe me that is quite a high tolerance, precision components are even tighter.

We set machines to be within +-0.05 mm if ever found to be over on QC inspection (extremely rare) entire batches were pulled, every component hand measured to ensure it didn't go beyond the maximum and signed off by a QC manager. Again this was using battered obsolete machines in a less than precision sector!

Moderators!

Please close this thread before some a******e from SRAM, Giant or Trek comes along and figures out some more unwanted component standards that become strangely incompatible with any frames bought in the last year.

I'd actually quite like a narrower handlebar standard.... keep your large diameter at the centre but some of us with small hands would like BOTH a reasonably small diameter grip AND some softness!

I think Juliana tried this with some of their bikes but alas, they're all really narrow.

Chester, I believe Mr Whiles has access to a CMM and the comment was tounge in cheek... 🙂

1 1/8" steerer/stem clamp had been around for a long time. Looked like we were heading 1.5 at one point.

Seatpost diameter used to be all over the place but seems to have settled down. No 40mm frame with integrated dropper yet...

Saddle rails. I'm pretty sure the seat from my 1984 road bike would fit my Reverb!

Handlebar grip diameter.

Water bottle boss bolt spacing...

Why do the pedals have to drive the rear wheel?

Front derailleurs. No one can work out a better system that isn't just shit, so the solution is 1x and bin the bloody thing 😛

Steerers / stems haven't changed much I'd like to see them splined or keyed so you can be sure the stem is aligned with the front wheel.

Saddle rails. I'm pretty sure the seat from my 1984 road bike would fit my Reverb

I was thinking this. A bit of tinkering around the edges with OS rails and ibeam but that's it.

PJM1974 - Member
Moderators!

Please close this thread before some a******e from SRAM, Giant or Trek comes along and figures out some more unwanted component standards that become strangely incompatible with any frames bought in the last year.

Too late, that's already going to happen later this year. Can't reveal details.

Valve types, why only two types??? Not trying hard enough, that's why.

Steerer bolt sizes, way too standard.

TWO wheels. Really?

If nothing else this thread shows how much has been thrown in the air recently

The control and grip section of the bars hasn't changed width yet

I think we just have 2 standards for connecting disc rotors to hubs

The way that we connect disc brakes to the frmae is suspiciously stable at the moment

BMX aside we still have the same chain pitch

cassette spacing is boringly regular

control cables come in worryingly few thicknesses

Metric hex all over the place!?!

Ok, I know some companies are fitting more and more torx to bikes, bless them.

But only two standards now? Is no one using their imagination here or what? Where are the Polydrives? The Robertsons? The 12 point flange? Do you think people invent these things for NOTHING?!???!!!

5/10, must try harder.

only problem with a splined stem is that in the event of a crash it would be more likely to wreck the fork or wheel meaning you cant ride home but the current arrangement allows you to twist the bars back

actually the bar diameter is a good one, if they screw about with it then you'll need different clamp sizes for brakes and shifters...

ampthill - Member

The way that we connect disc brakes to the frmae is suspiciously stable at the moment

That's because it's taken a lot of effort to make the move over to stupid ****ing rear PM.

Somewhat off topic but a mino link system into the head tube to adjust reach would be an interesting innovation.

Why oh why does no one do split clamps on shifters? It works fine for brakes why not a damn gear lever. Why do I have to remove everything from my bar to remove the shifter?

Switching the drive side to the left will be next. New frames, brakes, hubs, derailleurs...

cassette spacing is boringly regular

Other than it changing from 8-9-10-11. 😉
Also, Campag use a very slightly different spacing to Shimano/SRAM, just enough to make the shifting incredibly difficult to sort if you happen to be running Shimano gears with a Campag cassette.

Thankfully no-one has decided that chains should be any different, I guess that is one standard that is so ubiquitous worldwide that even trying to introduce anything else would be pointless.

Chain pitch? I think that all chains use the same spacing between pins / length of links?

Valve types, why only two types

There's three but carry on.

If nothing else this thread shows how much has been thrown in the air recently
The control and grip section of the bars hasn't changed width yet
I think we just have 2 standards for connecting disc rotors to hubs
The way that we connect disc brakes to the frmae is suspiciously stable at the moment

There are a lot more out there than you would realise. Ok not all mainstream but available.

Bars - Santa Cruz Juliana bars are available in narrower diameter for smaller hands. [url= https://totalwomenscycling.com/mountain-biking/mountain-bikes/juliana-bicycles-furtado-segundo-mtb-review-14431/#EGg0G1qrf3dLKttS.97 ]Link[/url]

Disc rotor mounts - 6bolt. Centre lock. Rohloff. (Also Hope 3 bolt. Hope 4 bolt.)

Frame disc mounts - IS. Post. Now Flat.

You also have loads of legacy stuff like old hope 5 bolt, Hayes 22mm mounts, 68mm post mount etc. Yes I'm a bike geek so I would know this but what it does show is how the market didn't take to them.

Is there only one thread for the rear derailleur to screw into

ampthill - Member

Is there only one thread for the rear derailleur to screw into

Nope, Shimano do a direct mount mech. Though, to be fair all their mechs are compatible with both, you just remove one of the links (are sram? Don't know).

[quote=edhornby ]actually the bar diameter is a good one, if they screw about with it then you'll need different clamp sizes for brakes and shifters...

They seem to manage different seat tube diameters with a single front mech clamp...

There's only one size of whee......hang on ,wait a minute.

There's only one standard response to mention of wheel sizes

[img] [/img]

STATO - Member
The problem of course with running very short cranks is your seat height is higher (presuming xc/road riding obv) so reaching the ground is near impossible. Ive seen people solve this by smaller wheel size, to bring the pedal-ground distance back to what it was with the designed cranks.

I honestly think it's cool that you've considered the implications.

But it's not as big a problem as you fear.

My wife has 140mm cranks on her hard tail (we had some sram s600's shortened by high path). They're only 25mm shorter than 165's which means her saddle is only 25mm higher. This even comes with 2 benefits: 1) it brings her saddle UP to the level of her bars, and 2) it exposes enough seat post to fit a dropper.

But here's the problem: they're square-taper, which won't fit in her new bb90 frame - she's stuck with the 165's that came with the bike (The S600's are also very heavy). I'd need to try 220mm cranks to see how bad her 165's must feel.

(When we ordered the bike, we were told it had a bb30, which CAN be adapted to accept her heavy square taper cranks)

Usually, crank-length isn't a problem for the extended leg : you can just adjust the saddle height. The impact of crank length is felt by the bent leg - where the effect is doubled: 165's aren't 25mm too long for my wife, they're [u]50[/u]mm too long.

So yes. You [i]can[/i] get 140mm cranks for your mtb, but you have to get them custom made. And you'll struggle to fit them to a new bike.

I know I'm boring you all, but it just seems daft, every [u]other[/u] component is widely available in a huge range of sizes. If nothing else, think of the weight savings!

Marin also do a low rise bar with a narrow grip section, I bought one for my wife's bike in my lbs, it comes with thinner grips and plastic shims for brakes and shifters.

awhiles

In summary the problem is bottom bracket standard not crank lengths. Not sure why you didn't return the bike?

Mrs Gasket uses 160mm Rotor cranks, that are HT2 so will slot into BB86/90.

She previously ran a set of square taper TA Carminas (in 160) but when we bought a new Giant frame they wouldn't fit the BB86, as you say, so we bought the Rotor cranks.

ampthill - Member
awhiles

In summary the problem is bottom bracket standard not crank lengths.

no. We had to get her square-taper cranks [i]made[/i]. They didn't exist until highpath made them for us.

...Not sure why you didn't return the bike?

because I was sure there would be some way of bodging it to accept her square-taper cranks, And then I worked out how to modify some deore ht2 cranks. I just think it's daft that Xs cranks weren't fitted to an Xs bike. It's even more daft that we can't buy Xs cranks separately.

We don't expect people who want short stems to have to make them from long stems. But that's what I'm faced with trying to get cranks for my wife's mtb. We're not talking about making special modifications to adapt a bike for an individual with disabilities, she's 5'1". In the world of women on bikes, that's one size smaller than average.

(My wife does have those Sjs thorn cranks on her road bike, 140mm, they're a suitable length, but heavy, and won't work on her mtb)

While logic would tend to suggest that smaller riders need shorter cranks, most studies on the area suggest that even wide variances in crank length have a marginal effect on power output. Therefore it doesn't make sense for manufacturers to produce a huge array of crank lengths when the extreme sizes are only going to have limited sales.

As for chain pitch Shimano did try 10mm pitch for a while...

[img] [/img]

Awhiles

But here's the problem: they're square-taper, which won't fit in her new bb90 frame - she's stuck with the 165's that came with the bike (The S600's are also very heavy). I'd need to try 220mm cranks to see how bad her 165's must feel.

You can see why I thought you hadn't solved the problem. I'm glad that you have.

Its an interesting question as to why bikes don't come with much shorter cranks on smaller frames. If its deigned in from the start the with extra BB drop you would just end up with the saddle at the same height and the same pedal clearance.

While logic would tend to suggest that smaller riders need shorter cranks, most studies on the area suggest that even wide variances in crank length have a marginal effect on power output. Therefore it doesn't make sense for manufacturers to produce a huge array of crank lengths when the extreme sizes are only going to have limited sales.

Mike Burrows (Chris Boardman's aero Lotus bike guru and all-round crazy inventor chap) has a theory that we should all be using much shorter cranks for a couple of reasons, one of which is that it would actually increase efficiency quite dramatically. He runs shorter cranks on his aero recumbents and gets good results, I believe. I think he reckoned that as low as 140mm or so was the optimum length for most riders (obviously you change gearing to adjust for the different leverage).

[quote=Sam ]While logic would tend to suggest that smaller riders need shorter cranks, most studies on the area suggest that even wide variances in crank length have a marginal effect on power output.

Studies carried out with riders close to average size AFAIK - and mostly with cranks shorter than "normal" rather than longer. Which would tend to suggest that it would be reasonable for all bikes to be supplied with shorter cranks than they are currently. Because for shorter riders having cranks too long results in biomechanical issues other than maximum power output.

I have a variety of crank lengths from 125 up to 175 and whilst I couldn't say whether I produce as much power on the shorter cranks or whether I'm as efficient, I'm comfortable using them and I'm not sure I would be with significantly longer cranks.

Sam - Member
While logic would tend to suggest that smaller riders need shorter cranks, most studies on the area suggest that even wide variances in crank length have a marginal effect on power output.

Firstly, there really aren't many 'studies', and those that have been done are scientifically very poor/limited, With no attempt to examine the impact of rider height on the results.

i.e. It seems no short people were used in the tests.

it does seem that there are few problems experienced by people using shorter-than-expected cranks. And few benefits of long cranks.

Edit: what aracer said.

ampthill - Member

Its an interesting question as to why bikes don't come with much shorter cranks on smaller frames. If its deigned in from the start the with extra BB drop you would just end up with the saddle at the same height and the same pedal clearance.

My wife loves the extra clearance offered by her 140's, the extra saddle height comes in handy too...