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Follow up thread - Handlebar heights - "dont chopper your bike" edition


Seths Pool
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So in the last thread I started, one of the main focus points was my concern about making my front end too tall with the accumulation of mandatory components (head tube length + headset spacers + stem + handlebars with various amounts of rise to allow the shifter to clear the top tube) stacked on top of each other on the front end of a new build. 

I discovered something surprising though this morning, but let me list some components first

smash build - 

29" wheel, 2.35 schwalbe magic Mary front tire, 160mm rock shox pike fork w/ 8" steer tube, 5mm of headset spacers under stem (with high rise bar config) , funnduro 45mm stem / 0 rise, spank 50mm rise bars 800mm

intense primer build - 

29" wheel. 2.35 schwalbe magic Mary front tire, fox 36 140mm fork with 7.5" steer tube, 3mm headset spacers under stem (basically slammed), chromag 35mm / 0 rise stem, chromag 25mm rise bars

so I normally like my front ends pretty dang low, comparatively to other peoples bikes I see that always seem to have pretty big stacks of headset spacers under there stems, usually run about a 20-25mm riser bar, 0 rise stem, and usually have the stem pretty slammed on top of the head tube/headset...  but is this "chopper-tall-front-end sensation" all in my head? I had the perception that my intense primer front end was low, like I know I like, someone at the last enduro event was even commenting on how low it seemed. but this morning before I left for work, I randomly decided to measure how tall my grips stood off the ground, and the results surprised me! 

quick measurement showed 44" at the top of my grips on the primer (29" wheel, 140mm fork, frame fits a 7.5" steer tube, 0 rise stem, 25mm rise bars) = 44" handlebar height

IMG_0006.thumb.JPG.f432efd570c2a2066b93a385b9ab23e3.JPG

the smash on the other hand (29" wheel, 160mm fork, frame fits an 8" steer tube, 0 rise stem, 50mm rise bars) = 43" handlebar height

 IMG_0005.thumb.JPG.993513488906a4014bad0444221232c1.JPG

(and yes, I know that I have the smash's stem UNDER the headset spacers, this is because the 50mm rise bars was more than I needed to solve the clearance issue)

 I didnt get super precise measurements this morning but you still get my point. the proof is obviously there in all the math if I wanna take time to measure it all, but I'm feeling like "how"? the smash has a longer fork, longer head tube, and taller rise bars, how is it even possible to be equal or shorter than the primer front end?? I did just think about taking into account HTA, but still..

but it seems to me at this point that this "front end too tall" issue is mainly in my head. partially because Im frustratingly aware of the large riser bars I dont exactly love, and the bike just aesthetically just seems to look taller and larger.

any thoughts?

 

Edited by Seths Pool
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The measurement from the ground may be erroneous in regard to fit. You might want to make other measurements from the handlebar tips and center to spots like the nose of the seat and center of the crank. These numbers will be better related to how they fit when riding. Further, getting angles on those lines measured might offer some insight as well.

Edit: Yeah, what TheX said.

Edited by Ridenfool
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I was going to jump in with the same thing. There are too many variables involving BB drop, BB height, frame angles, wheel sizes, suspension sag, etc to make your measurements meaningful. measuring the height of your grips from the ground is meaningless because you're not standing on the ground when you ride the bike. You're standing on your pedals, I hope.

How far are your grips from the BB? In a straight line? Vertical/ horizontal?

For a visual reference, look at what Lee McCormack and Lenz call "RAD" Rider Area Distance- http://lenzsport.com/bicycle-fit/

Take saddle position out of the equation. Don't even think about saddle position until you know exactly where your hands are relative to your feet. Optimize that so you can wrangle the bike while standing up, then work on your seated pedalling position.

With your bike upright and propped up with your back tire against a wall, measure from the ground to the center of the BB. Then measure from the ground to the grip. Subtract the from from the latter. That's your effective stack.

Now measure, as best you can, from the wall to the BB, and from the wall to the midpoint between your grips. That's your effective reach.

Measure the direct distance from the center of the BB to the midpoint between the grips. That's your RAD. It does not change because the front triangle of your bike is static.

Are those measurements different between the two bikes? If they are, should they be the same based on how and where you ride them? Otherwise, unless you have Go Go Gadget limbs, your body proportions don't change, so there's no reason to have different measurements from one bike to another for the same rider.

Edited by mack_turtle
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34 minutes ago, mack_turtle said:

I was going to jump in with the same thing. There are too many variables involving BB drop, BB height, frame angles, wheel sizes, suspension sag, etc to make your measurements meaningful.

How far are your grips from the BB? In a straight line? Vertical/ horizontal?

For a visual reference, look at what Lee McCormack and Lenz call "RAD" Rider Area Distance- http://lenzsport.com/bicycle-fit/

Take saddle position out of the equation. Don't even think about saddle position until you know exactly where your hands are relative to your feet. Optimize that so you can wrangle the bike while standing up, then work on your seated pedalling position.

With your bike upright and propped up with your back tire against a wall, measure from the ground to the center of the BB. Then measure from the ground to the grip. Subtract the from from the latter. That's your effective stack.

Now measure, as best you can, from the wall to the BB, and from the wall to the midpoint between your grips. That's your effective reach.

Measure the direct distance from the center of the BB to the midpoint between the grips. That's your RAD. It does not change because the front triangle of your bike is static.

Are those measurements different between the two bikes? If they are, should they be the same based on how and where you ride them? Otherwise, unless you have Go Go Gadget limbs, your body proportions don't change, so there's no reason to have different measurements from one bike to another for the same rider.

 

1 hour ago, TheX said:

For me, height from the ground is not as important as height in relation to the BB and the seat. 

 

1 hour ago, Ridenfool said:

The measurement from the ground may be erroneous in regard to fit. You might want to make other measurements from the handlebar tips and center to spots like the nose of the seat and center of the crank. These numbers will be better related to how they fit when riding. Further, getting angles on those lines measured might offer some insight as well.

Edit: Yeah, what TheX said.

 

you guys obviously have a deeper understanding of FrameGeoNerdology (FGN) than I do, and thanks for everyone's input. I thought the simple vertical height measurement of where you control the bike from would play more of a factor, but I guess not. 

but I'm still intrigued on how the smash's front end is measuring shorter than the primers front end regardless of how the other measurements play into performance and fit.. id expect same 29" wheel + 2.35 tire + longer fork + longer headtube + higher rise bars > 29" wheel + 2.35 tire + shorter fork, shorter headtube + less rise

 

 

Edited by Seths Pool
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I always just set it up to whatever feels best to me. Trying to duplicate the same cockpit on multiple bikes doesn't make any sense as each bike has different geo/purpose/design and will never feel like the next. I've had a couple dozen bikes since 2012 and would have gone batsh*t crazy by now.

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Just now, ATXZJ said:

I always just set it up to whatever feels best to me. Trying to duplicate the same cockpit on multiple bikes doesn't make any sense as each bike has different geo/purpose/design and will never feel like the next. I've had a couple dozen bikes since 2012 and would have gone batsh*t crazy by now.

I think more than anything else I just hate the freaking red spank 50mm rise handlebars I bought in impatience to solve the clearance issue. haha

Im not loving the red, and the rise bend is too much for me. I feel like my bike has bull horns

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1 hour ago, Seths Pool said:

you guys obviously have a deeper understanding of FrameGeoNerdology (FGN) than I do, and thanks for everyone's input. I thought the simple vertical height measurement of where you control the bike from would play more of a factor, but I guess not. 

You're starting with a flawed premise- that comparing measurements from the ground- is a useful baseline, them comparing apples and oranges. Those are different bikes different geometries.

My description sounded complex, but it boils down to this: your ability to wrangle the bike depends on where your hands and feet are. Find a distance that works for you and use that as a baseline. You might end up raising and lowering the grips but that distance remains about the same because - geometry. It might not work on every bike, but it's a good starting point.

Raising the handlebar to avoid hitting your top tube or trying to make the height from the ground match another bike is going to compromise handling in the end.

Edited by mack_turtle
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1 hour ago, Seths Pool said:

 

 

 

you guys obviously have a deeper understanding of FrameGeoNerdology (FGN) than I do, and thanks for everyone's input. I thought the simple vertical height measurement of where you control the bike from would play more of a factor, but I guess not. 

but I'm still intrigued on how the smash's front end is measuring shorter than the primers front end regardless of how the other measurements play into performance and fit.. id expect same 29" wheel + 2.35 tire + longer fork + longer headtube + higher rise bars > 29" wheel + 2.35 tire + shorter fork, shorter headtube + less rise

 

 

I agree with you that I would have assumed that the one with taller stack up of headtube, fork and bar rise would have measured taller. If it were mine, I'd wonder if the Smash was set to a lower travel setting or stuck down. Do the travel markers show the right value when unweighted? I know it's more slack but that is quite a difference.

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10 minutes ago, Anita Handle said:

but I also agree with the others that a measurement to the top of your seat would help in understanding the relative height of your bars.

Measurement comparing to saddle height from the ground, if that's what you mean, is a red herring. It does not take BB hieght I to account. Throw sag in there and you're chasing your tail. Now put a dropper post in the equation and you're just wasting time. Your seated pedalling position has nothing to do with wrangling the bike.

Effective reach and stack start with the BB isolated in space and determine your range of motion. This is the gold standard to start fitting a mountain bike.  if you're fitting a road bike, where your seated pedalling position is important, that's a different story.

Edited by mack_turtle
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47 minutes ago, mack_turtle said:

Measurement comparing to saddle height from the ground, if that's what you mean, is a red herring. It does not take BB hieght I to account. Throw sag in there and you're chasing your tail. Now put a dropper post in the equation and you're just wasting time. Your seated pedalling position has nothing to do with wrangling the bike.

Effective reach and stack start with the BB isolated in space and determine your range of motion. This is the gold standard to start fitting a mountain bike.  if you're fitting a road bike, where your seated pedalling position is important, that's a different story.

I thought the gold standard was Hopping Up On That Badboy And Yanking It Up To Your Junk?

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2 hours ago, mack_turtle said:

Effective reach and stack start with the BB isolated in space and determine your range of motion. This is the gold standard to start fitting a mountain bike.  if you're fitting a road bike, where your seated pedalling position is important, that's a different story.

 

If anyone wants a distilled version of whats being discussed, then this is the substance of it all.

Additionally, I'd never considered your suggestion on how to determine effective reach by measuring to the back wall.  Thats a very good suggestion.

-CJB

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18 minutes ago, CBaron said:

 

Additionally, I'd never considered your suggestion on how to determine effective reach by measuring to the back wall.  Thats a very good suggestion.

-CJB

I got that from a discussion of comparing and duplicating saddle setback. More relevant to road bikes, but if you find a saddle you love and want to put the saddle at exactly the same distance from the BB every time, measure from the wall to the BB and from the wall to the saddle nose. The difference is your saddle setback or offset or buttback or whatever you want to call it. What do you want to call buttback from now on?

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