How do I work out how much to increase stem length?

[GoLefty!!]

Because it's only you feeling the leverage of the bar at the pedals. No scientific measurements reflects this phenonmenon. It's all in your head

[Iwan Kemp]

http://www.vitalmtb.com/features/Modern-Mountain-Bike-Geometry-Defined-Transition-Explains-Effective-Top-Tube-Versus-Reach,841

 

Selah.

[Captain Fastbastard Mayhem]

http://www.vitalmtb.com/features/Modern-Mountain-Bike-Geometry-Defined-Transition-Explains-Effective-Top-Tube-Versus-Reach,841

 

Selah.

Exactly.

[EmptyB]

http://www.vitalmtb.com/features/Modern-Mountain-Bike-Geometry-Defined-Transition-Explains-Effective-Top-Tube-Versus-Reach,841 Selah.

Very good!

[arendoog]

I am the same height as the op 194cm. I ride 4different bikes .?The bikes with the racing geometry both make my hands numb ,road and racing HT .The other 2 have more trail ,upright geometries and one has a longer fork 120mm .It is my opinion that the frame geometry is by far the most impotant reason for numb hands .More forward weight is great for climbing ,but not good for long flat riding when most of the weight is over the bars .The best solution is to get a longer fork or have an angled seatpost ,or higher bars to get the weight back .Gripping lightly and having strong core muscles certainly help too ! Wider bars on a racing geometry bike will put even more weight forward

[GoLefty!!]

Exactly what? An All Mountain bike manufacturer providing their opinion on fitting an all mountain bike. Heck they even state that unless you're a XC type the short stem wide bar is a good idea. That has never been in dispute in this discussion. The only dispute is Myles incessant need to bludgeon his ideas as categorical gospel truth into every poor sod who crosses his path.

 

Theres nothing new, revolutionary or ground breaking in that article .......if you're an AM rider.

 

If you're an XC rider you are going to have other considerations besides how your bike handles the down hill singletrack.

things like,

- lightest frame that will fit

e.g If I could fit on a medium and a small and the medium required a 60mm stem while the small required a 90 I'd be on the small simply because the small would be the zippier bike up singletrack and would be more responsive to where i place my weight. Saddle to bar distance will be the same if the bike has been fit correctly.

 

 

But please keep preaching to us all how we all need to be AM riders

[Captain Fastbastard Mayhem]

Exactly what? An All Mountain bike manufacturer providing their opinion on fitting an all mountain bike. Heck they even state that unless you're a XC type the short stem wide bar is a good idea. That has never been in dispute in this discussion. The only dispute is Myles incessant need to bludgeon his ideas as categorical gospel truth into every poor sod who crosses his path.

 

Theres nothing new, revolutionary or ground breaking in that article .......if you're an AM rider.

 

If you're an XC rider you are going to have other considerations besides how your bike handles the down hill singletrack.

things like,

- lightest frame that will fit

e.g If I could fit on a medium and a small and the medium required a 60mm stem while the small required a 90 I'd be on the small simply because the small would be the zippier bike up singletrack and would be more responsive to where i place my weight. Saddle to bar distance will be the same if the bike has been fit correctly.

 

 

But please keep preaching to us all how we all need to be AM riders

 

 

FIrstly, Transition do NOT just make AM bikes. They make bikes across all spectra. 

 

Secondly, you're being just as if not more vehement with your opinion, calling everyone else's opinion BS and just generally being a bit of a cretin when someone disagrees with you. 

[Captain Fastbastard Mayhem]

But anyway. I'm out. It's clear that you're not going to change your opinion, or agree to disagree with someone, despite the overwhelming evidence in favour of shorter stems and wider bars even in XC applications. In my opinion, unless you're a racer, in XCM disciplines or something else that doesn't have anything technical in it, you should be on a short stem and wide bar rather than long stem and narrow bar. It just allows that much more control. End Of Story. 

[GoLefty!!]

But anyway. I'm out. It's clear that you're not going to change your opinion, or agree to disagree with someone, despite the overwhelming evidence in favour of shorter stems and wider bars even in XC applications. In my opinion, unless you're a racer, in XCM disciplines or something else that doesn't have anything technical in it, you should be on a short stem and wide bar rather than long stem and narrow bar. It just allows that much more control. End Of Story. 

http://www.transitionbikes.com/2015/Bikes.cfm?Token={ts_2015-02-06_14:52:52}-ee20010ffe0a819a-C6A9987B-C9B5-0D65-6002AF579CB00FCE

 

 

Don't see anything marathon or XC in this line up.

 

I am not advocating what people should use (unlike you) I am advocating that they get themselves properly fit on their bikes and decide how they want to adapt the bike once they've ridden the darn thing. I don't believe that your one dimensional thinking helps anyone solve a problem.

But you are great at google....

 

 

"It's clear that you're not going to change your opinion"

 

speaks volumes as to your agenda.

[Skylark]

leverage on the cranks is determined by the length of the cranks themselves, including the length of your femur for seated pedalling. The only motive force acting on the pedals is muscular

For standing pedaling, its length strength + body weight.

 

So the question is, how does bar width affect these sources of motive force? For standing pedalling, not much I believe. it may move your center of mass to the point that it changes where in the rotation the crank, you start a pedal stroke. That's a case for efficiency, not leverage.

 

For seated pedalling however, it can affect which muscle groups are relied upon to drive the cranks. So narrower bars might push some riders further back on their saddle, while wider bars might force the driver to come further forward. It changes the pedaling efficiency due to changes in which muscles are engaged.

 

So in a nutshell, the wider bars may just have changed your riding position to one that's more effective at pedalling than before. Bar length doesn't change your mass, femur length, or crank arm length.

 

Capricorn thanks for taking the time to explain your understanding to me without sanctimonious, makes it so much easier to absorb the info, appreciated

 

I can understand wider bars can't take anyone past their bodies/leg/bike setups's theoretical max pedal force/output, leverage or whatever that force is called that makes the cranks rotate under load but it could perhaps help you to get closer to it and more efficiently?

 

The leverage of the bars, wider(within reason) having more leverage than narrower and all other things being equal(shorter or longer stem to keep the reach/riding position the same), must have some bearing on the pedalling power/efficiency because if you take your hands off the bars whilst riding you can't push very much power into the pedals?

 

And when you stand up riding up a steep hill the leverage of the bars appears to come into play even more so, if you take your hand off the side of the bars opposite to the pedal being stroked, ie remove the balancing force at the opposing leverage point, you'll slam straight into the ground.

[RockCoach]

If you've ever ridden a SS up a steep bank where you are straining to turn the cranks, you would appreciate the extra leverage of wider bars for climbing.

 

As your right foot powers down onto the pedal, your right hand is pulling up on the rhs of the bar with considerable force. A bar which is wider (within reason) gives you more leverage between bar and pedal and thus more force on the pedal. Try it. It works on all bikes in steep climbing situations.

[VicanZA]

I used to suffer from numb hands, u putting to much weight through the hands.

 

Changed my grips to the ergo and problem solved they will correct the hand position on the bars.

 

What fingers are going numb? Is it ulnar nerve intrapment or carpal tunnel?

[Pieter1]

If you've ever ridden a SS up a steep bank where you are straining to turn the cranks, you would appreciate the extra leverage of wider bars for climbing.

 

As your right foot powers down onto the pedal, your right hand is pulling up on the rhs of the bar with considerable force. A bar which is wider (within reason) gives you more leverage between bar and pedal and thus more force on the pedal. Try it. It works on all bikes in steep climbing situations.

I can vouch for this.

[RockCoach]

I can vouch for this.

I may have forgotten to include that this applies to standing climbing...

[Pieter1]

I may have forgotten to include that this applies to standing climbing...

I'll vouch for that to.

[GoLefty!!]

I don't feel any difference in ability to apply leverage to the pedals with any bar between 780mm and 580mm. Buts that's probably because I apply leverage through my legs and not through my arms