Q Factor, quack quack..

[Tootyred]

I'm not sure if this is a world I really want to enter....im worried its just another thing get obsessed about!

The race face cranks are a pain, they have an appalling concept of chain line measurements (it's a common complaint with them) even on a 107 bb. They cost me nothing but a drink and to be frank swapping back to my comfy, go to slippers of m730 175mm is the next option on my list.

Interesting topic for more bedtime reading and it's made me think about my poor knees. Which I can tell you all from experience (painful experience) are trouble when they go wrong.

 

[lensmansteve]

Fair enough, tooty. Knees are indeed precious. Very, very painful when they're not happy. They're doing all kinds of movements when we're just walking, let alone all the high stress stuff like playing football. At least cycling is potentially low impact, depends on the sort of cycling! Some body weight shared by the arms and sit bones, of course, and that helps them. That's a fundamental advantage that means, ultimately, that we can go faster and further on a bike than on our feet. Not forgetting ball bearings of course, without which we'd have a very big struggle.

 

[Woz]

I'm not sure if this is a world I really want to enter....im worried its just another thing get obsessed about!

Come on in and let me offer some sweets and snake oil. At the very least, it's being discussed here and not
hidden. You will not find a single mention about Q-factor when you buy a new Shimano crank and look
at the enclosed tech doc / installation / destruction manual. Instead you will get plenty of shit about torque,
BBs in every flavour, 20 zillion references to other products, in about 8 million different languages to study.

Pick your poison.

 

[lensmansteve]

That's the way it is, Woz. I guess there's no way the distance between cranks can ever be marketed to look sexy, or macho or anything desirable. Not like the sculptural form of a crank (even if they scrape your ankles, see earlier post re Mavics) or the castings of a suspension fork. It's the usual style over substance.
Went out between the showers today on different bikes, with the Qs in mind, at least some of the time. Just confirmed what we've been on about, you really can feel the difference, and the harder you pedal, the more the difference is apparent. May have to swap a few cranks and bb's I reckon. A bit of "practise what you preach" never goes amiss. I reckon this thread has done what I hoped it would, it's the first thread I've posted and has been more up my alley than the "What colour does everyone think I should paint my '91 Tamagochi?" sort posted by members I wouldn't trust to adjust hubs properly. Where did that come from ?

 

[2manyoranges]

Re:

I reckon that Shimano knew that you were about to start this topic, since a short while ago they began to publish the Q on all their cranks. This was precipitated by the emergence of B1 B2 variants of SLX XT and XTR - to deal with the irritating new 'standards' of 142 AND 148 boost rear ends. Someone need to shout "IT'S HARDLY A BLOODY STANDARD IF YOU HAVE SO MANY OF THEM!!!" - there said it now.

My workshop used to have lots of wheel sets. These varied by spoke number, rim width and brake type. NOW IT'S FULL OF 29, 27.5, 26, 150 spacing, boost 142, boost 148, 135, 100 and 110 - and 15mm, 10mm and 20mm axle standards - and 9, 10, 11 and 12 speed free hubs. And tubes, tubeless. It's mad. MAD. No wonder I can't remember the name of my kids (of which I have two, and they live somewhere in the same house) when I have to remember what available wheelset I have for each bike. The only HOPE in all of this (see what I did there) is that Pro2 EVO hubs and Pro4 can be adjusted with their excellent pop in and out adapters. Thank you the fine folk of Barnoldswick.

The Transition Sentinel which I am building at the moment has a 73mmm BB - great I thought, I'll use a gorgeous XTR 165 crankset I have. Apart from the fact that it's 148 boost at the rear and when I put it in I can't run the gear cable through the right routing AND have a chain device on while running a non-boost 48mm chain-line low Q XTR chainset. WHAT!!!!?! I have had to buy an XT M9000-B1 53mm chainline crank and see the XTR go back onto the shelf in all it's 550grams of loveliness. BONKERS.

Such is modern life. But Q seems to be back. Where's M gone?

 

[Woz]

Re: Re:

I reckon that Shimano knew that you were about to start this topic, since a short while ago they began to publish the Q on all their cranks. This was precipitated by the emergence of B1 B2 variants of SLX XT and XTR - to deal with the irritating new 'standards' of 142 AND 148 boost rear ends. Someone need to shout "IT'S HARDLY A BLOODY STANDARD IF YOU HAVE SO MANY OF THEM!!!" - there said it now.

My workshop used to have lots of wheel sets. These varied by spoke number, rim width and brake type. NOW IT'S FULL OF 29, 27.5, 26, 150 spacing, boost 142, boost 148, 135, 100 and 110 - and 15mm, 10mm and 20mm axle standards - and 9, 10, 11 and 12 speed free hubs. And tubes, tubeless. It's mad. MAD. No wonder I can't remember the name of my kids (of which I have two, and they live somewhere in the same house) when I have to remember what available wheelset I have for each bike. The only HOPE in all of this (see what I did there) is that Pro2 EVO hubs and Pro4 can be adjusted with their excellent pop in and out adapters. Thank you the fine folk of Barnoldswick.

The Transition Sentinel which I am building at the moment has a 73mmm BB - great I thought, I'll use a gorgeous XTR 165 crankset I have. Apart from the fact that it's 148 boost at the rear and when I put it in I can't run the gear cable through the right routing AND have a chain device on while running a non-boost 48mm chain-line low Q XTR chainset. WHAT!!!!?! I have had to buy an XT M9000-B1 53mm chainline crank and see the XTR go back onto the shelf in all it's 550grams of loveliness. BONKERS.

Such is modern life. But Q seems to be back. Where's M gone?

I've read this about five times. Is there new shit out there? Jeeesus. I'm just progressing to M750.

 

[mattr]

From reading one of the papers about biomechanics (15 years ago), bad knees is usually crank length (which is mostly impacted by femur length and knee/hip flexibility, not inside leg or height.)
Hip problems is mostly Q factor and ankles are just shit and can be broken by anything.........

 

[2manyoranges]

Re:

mattr hmmmm up to a point Lord Copper. The Quads are huge muscles, and the energy is transmitted to the bike through the knees down to the pedals. I think Q has an impact on knees too - I think it should all be seen as a linked system....which article/paper are you referring to? I'd be interested in reading it if you have a moment to put up the reference.

OK...someone had to do it:

The ankle bone's connected to the...shin bone
The shin bone's connected to the....knee bone
The knee bones' connected to the......thigh bone

 

[2manyoranges]

Woz - bad news....

Elvis is dead.

 

[legrandefromage]

No isnt, he just went home.