Fitting yourself for a new Stem + Crank Size

Krause said:

heya guys, how do you guys go about properly fitting yourself for a new Stem? if i find mine is a bit too short how do i go about finding the exact right length without haveing other parts lying around to swap and test on? When fitting reach like that do you also change the rise of the stem ( maby handlebars too? from riser to straight)

Also if you replace a crank you have length choices, is that something that is specific to frame type or riding type or is that something you change based on a fitting situation?

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STEM: go with whatever feel right. Longer will stretch you out and shorter won't. If you want to be more upright than get one with a rise or like you said get riser bars. Combine all these elemets to fit your body/pfreference.... there is no "right" way.

Jwind said:

STEM: go with whatever feel right. Longer will stretch you out and shorter won't. If you want to be more upright than get one with a rise or like you said get riser bars. Combine all these elemets to fit your body/pfreference.... there is no "right" way.

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Im sorr, i should of been a bit more specific, i was looking more along the lines of how to tell the size, like lets say a stem comes in increments of just a few mm, how do you chose the right size usually without testing them, just kinda estimate and hopwe its right and if its not, you know for next time?

Thank you though

I agree with JWIND. I recently picked up a 90mm 10 degree rise easton stem for my bike. That matched with my low rise bar fits me perfect. I like to ride how I am comfortable.
Picking out different sizes may also be a trial & error thing.

well, you can go and get yourself professionally fitted (about $150) or use wrenchscience.com to determine sizing.
As for testing the stems, you should be able to go to your LBS and try a few different stems for test rides to see how different lengths and rises feel.(If you do that, Please don't then go buy a stem off the internet just because you can get it $5 cheaper).
As for cranks, most use 175mm, and most bikes come standard with that length, except for very small bikes may come with 170mm. Again, your LBS may have cranks you can test, but I wouldn't be surprised if they only had 170mm and 175mm (maybe 172.5 and 180 if you're lucky)

Krause said:

heya guys, how do you guys go about properly fitting yourself for a new Stem? if i find mine is a bit too short how do i go about finding the exact right length without haveing other parts lying around to swap and test on? When fitting reach like that do you also change the rise of the stem ( maby handlebars too? from riser to straight)

Also if you replace a crank you have length choices, is that something that is specific to frame type or riding type or is that something you change based on a fitting situation?

Click to expand...

Stems come in length and degree of rise. The length is usually measured from the nut in the center of the headset to the end of the stem (and in mm). There is also a degree rise that you have to factor into the stem from 0-15 degrees for MTB.

Bars come in flat models and riser bar models...

As someone else said, there is no 'right' way, if you know your current setup and don't like it, get more in where you want your hands to be. Make sure that the bar and stem you get are both the proper diameter, too.

Just about every crank you'll use will be a 175.

it's not to the end of the stem, it's from the center of one hole to the center of the other. find out what you have, and estimate what angle you want your upper body

stem size

You can also look at sliding your seat back or forth.Also the set back of the seat post or lack of.A shorter stem/seat set back lets you get the front end up easier to get over obsticals.

kidd said:

it's not to the end of the stem, it's from the center of one hole to the center of the other. find out what you have, and estimate what angle you want your upper body

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Well, that's what I meant, when the end bracket is removed, you're looking at the center point where the handlebars will be.

I just can't show it here

Thanks, tho

I thought you wanted to try to get the stem the right length such that when you sit in your riding position the handle bar will obsecure the view of the front hub...

I tried it like that and noticed that the climbing on the bike suffered really bad and put it back to original. However I stretch quite a bit with the original stem. I may try a rider bar so that my handle bars are higher.

Cool thanks guys

BTW i was lookin at various cranks and as you said, its usually 170 and 175 (175 seeming to be the standard) but XTR makes a 180, now outta curioisty, what would that be used for? longer legs, a different frame or specific riding type?

from a physics standpoint the longer crank arm would generate more torque for the given amount of force your leg applied per stroke. Meaning more power? more efficiency? I'm not entirely sure as I have never ridden anything but a 175 mm crank arm length. Would it be more difficult to ride in really rough terrain, i.e. it hits rocks and stuff as you try to pedal through stuff?

Krause said:

Cool thanks guys

BTW i was lookin at various cranks and as you said, its usually 170 and 175 (175 seeming to be the standard) but XTR makes a 180, now outta curioisty, what would that be used for? longer legs, a different frame or specific riding type?

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for longer legs, usually. But a lot of people also like to use a longer than normal crank for singlespeed. They'll use a 175 on their geared bike, but a 180 on their SS. Longer crank gives more leverage.

If you look for it, you can find cranks made up to 220mm, as well. 'Course, you need to be about as tall as Shaq to use them!