[Doug]

How long is your torso? Bike sizing question...

Should we be using torso length to determine bike size/fit? Its pretty easy to get a smaller frame to have the right height seat. Standover is rarely an issue with modern bikes.

Whenever I go demo a bike (15+ in the last few months) they look at me and say, "you are a XL or even XXL". Why? I'm 6'4".

However, when I'm fitted for a backpack, I am a Medium or Large with my 19.5" torso (measured from top of hips to C7).

Modern bikes and fit are more about top tube length than standover/seat tube. So why do we still fit bikes based on height? One shop told me I'm a XXL Tallboy. I rode it and felt super stretched out and could barely reach when making tight turns.

I'm curious, what size bike are you on? What is your height? How long is your torso?

XL Tallboy LTc
6'4"
34" inseam (pant size)
19.5" torso (hip to C7)
26.75" torso (crotch to sternal notch)

 

[06HokieMTB]

Crazy. I'm 5'10" and have something around a 20" torso length. I also have long arms, wear 35/36 sleeve length dress shirts. I always rode mediums because of my height and could never figure out why my lower back would hurt.

I have been fitted and quite comfortable on bikes with 25.2" ETT with a 50mm stem and 800 bars. (Which was an Xl about 2-3 years ago). But I need an 18-18.5" seat tube to run a 150 dropper and for standover.

The last time I got fit, they said I was 6'3" from the waist up.

 

[Doug]

Went to a shop and again had the sales drones fitting me based on height. The more I look into this the more I'm convinced height is a minor player in bike fit. I think the two biggest factors are torso and arm length. Those effect frame size more. I noticed how getting my bike fit dialed meant playing with bar width too. Not just for riding style and preference. I really feel better and get less back, neck, and hand pain when using 787mm bars.

Its all a balance to get a good fit, and height dominates the process too much IMO.

 

[Harold]

I agree with you, but there are other concerns WRT bike fit.

I know guys who have the typical "tall guy" body proportions: short torso and long legs. On so many mountain bikes, they still wind up with a bad fit that pitches them over the bars and makes the bike handle like crap. These folks need a bike with more stack, or to mess with stem rise and riser bars (and from what I've seen locally, very few actually do this).

My wife has the opposite problem. she has a slightly longer torso for her height (and therefore short legs), but she also has short arms. It's extremely difficult for her to find a comfortable bike. And with how mtb geometry has been changing over the past several years, her next bike is going to have to be a size smaller than she's been riding.

I'm not terribly unusual in my fit, and I'm lucky in that regard. I can grab pretty much any medium and be comfortable. I can even climb onto some smaller larges and do pretty well (although I have less range of motion above the bike and that makes me less confident when the trail gets rowdy).

Long torso/short inseam people like 06HokieMTB are going to have inseam concerns. More confident/skilled riders might be willing to deal with less (or no) standover, but beginners won't.

Backpacks are relatively easy, since there are only a couple of relevant dimensions that are fairly independent of each other (you can swap hip belts on most of the nicer, burlier packs, for example). Bike fit deals with a lot more relevant dimensions of your body, which makes it more difficult to achieve an ideal fit for someone at the ends of the bell curve.

 

[06HokieMTB]

^Yep. Luckily I'm not thaaat concerned with standover as it's rare for me to straddle the bike flat footed on the trail. I do want 150mm droppers to fit - tough with 30" inseam legs. I need an 18-18.5" seat tube. Yes, I have resorted to cutting seat tubes down.

 

[evasive]

I'm 6'3" and have a long torso. I don't remember my cycling inseam, but usually buy 32" jeans.

I ride large or extra large frames depending on the application and how I want the bike to fit and handle.

 

[andytiedye]

Cycling inseam about the same as jeans inseam
because jeans shrink when washed.

Someone with a 32" inseam may not care about standover too much.
Someone with a 28" inseam (like me) needs to.

 

[targnik]

6ft, 32 inch inseam, 6ft 5inch wingspan...

Wide bars & long reach don't bother me so much.

Ridden L 650b Kona Process 134 & XL Transition Bandit 29er.

I think an important overlooked aspect is getting your bike to fit you ^^ i.e. no bike out there is designed specifically for one person.

Personalization is part of the process.

Sent from my kltedv using Tapatalk

 

[bachman1961]

6ft, 32 inch inseam, 6ft 5inch wingspan...

Wide bars & long reach don't bother me so much.

Ridden L 650b Kona Process 134 & XL Transition Bandit 29er.

I think an important overlooked aspect is getting your bike to fit you ^^ i.e. no bike out there is designed specifically for one person.

Personalization is part of the process.

Sent from my kltedv using Tapatalk

Yeah, I agree.

I'm on an 18" Kona that has always worked pretty well for me (as far as I know) but there is some play and shortly after I got it, I experimented with the seat rail position and added a longer stem. Not sure of all Kona bikes or current trends but this is an early 2000 and I get the feeling they are/were small-ish and tight cockpit.

I"m 5' 10.75" and about a 32 inseam so as I read up and learn more about fit/size with reach and stack being the primary numbers, I'm at the point where I've picked what I think will be a good next bike so the next step is test riding and playing the fit game on a 19" or a 17". I did a parking lot ride on a 19" Jamis Dragon Sport 27.5 and I need to revisit that again and try one size down just to see how it feels. I'm hoping for a definitive answer / gut feeling.

 

[bachman1961]

I'm curious, what size bike are you on? What is your height? How long is your torso?

XL Tallboy LTc
6'4"
34" inseam (pant size)
19.5" torso (hip to C7)
26.75" torso (crotch to sternal notch)

18" frame on 26" wheels Hardtail currently and rethinking the next purchase / frame size.

5' 10.75"
32 inseam
19" hip to C7 (approx) hard to measure on my own...
27" torso
29" arm length (if I did it correct) - my shirts are about a 34 sleeve.

Almost every chart I see about bikes and body dimensions shows both M and L frames as 6' transition. Some companies even list their M bikes as M/L then on to XL XXL. It really has to be case by case with specific brands, how they measure and your own feeling / ride experience.

My guess is this newer trend for reach and stack is a great tool for simplification and works well for 80 to 85 % of body types but there will always be some exceptional variations.

In the midst of it all, people like me who bought a bike in the early 90's and again in early 2000 have to keep getting retrained of the how the process has changed, variations in manufacturers, type of riding we do and the changes in frame geometry as well.

 

[stripes]

Should we be using torso length to determine bike size/fit? Its pretty easy to get a smaller frame to have the right height seat. Standover is rarely an issue with modern bikes.

Whenever I go demo a bike (15+ in the last few months) they look at me and say, "you are a XL or even XXL". Why? I'm 6'4".

However, when I'm fitted for a backpack, I am a Medium or Large with my 19.5" torso (measured from top of hips to C7).

Modern bikes and fit are more about top tube length than standover/seat tube. So why do we still fit bikes based on height? One shop told me I'm a XXL Tallboy. I rode it and felt super stretched out and could barely reach when making tight turns.

I'm curious, what size bike are you on? What is your height? How long is your torso?

XL Tallboy LTc
6'4"
34" inseam (pant size)
19.5" torso (hip to C7)
26.75" torso (crotch to sternal notch)

What are your thoughts on the shorter folks?

5'4"
29.75in inseam
Small ibis Mojo hd3 but I could ride a medium
Small Demo 8
P3 pro (one size fits all, 50mm stem and 750mm bars)

I have to test ride everything, because i fit anything from an XS (yeti), but usually a small, and sometimes I can fit a medium. All depending on the brand.

Stand over is important to me as even being female the few times I've ended up straddling the top tube (stalling on climbs usually), it's not been fun.

 

[JoePAz]

...Modern bikes and fit are more about top tube length than standover/seat tube. So why do we still fit bikes based on height? One shop told me I'm a XXL Tallboy. I rode it and felt super stretched out and could barely reach when making tight turns.

I agree on top tube length. I am 5'7" and had been riding a "medium" 17" 26" HT for years. Most "medium" 29ers felt huge. I did demo day on Pivots and rode a medium Pivot LES 29. I also felt super stretched when turning and knew it was not for me. Then a rode the small 429SL. Man that bike feel dialed in. What was the different. 1" of Top Tube length. Since then I used that a factor in bike fit/sizing. I bought 3 bikes since then and factor that I used fit is ETT.

Currently my bikes
SC Highball is "medium" with 22.9" ETT and 90mm stem
SC Solo (Vers 1) "Large" with 24" ETT and 50 mm stem (sized up, but works fine with shorty stem and is my mini DH rig)
Vassago Verhauen "Small" with 23.6" ETT and 80mm stem

So what "size" am I? The Solo is a bit big, but I think the longer TT helps with downhill stability and it my bike for riding the super chunky downhill terrain. I don't do big jumps. I would not run that long of TT and short stem on my more XC oriented bikes.

 

[Muirenn]

There is such a thing as effective torso length, too. The position of your back can effect reach (not the bike's reach, your reach), how curved over or straight your back is. It's a lot more apparent on road bikes. Arm length matters, too. So too stack, reach, head tube angle.


I'm 5'7" with a 33.3 (bike shop measured) inch inseam and long arms. And I need a medium frameset in most mountainbikes. I don't need any setback in the seapost due to KOPs. (Even in road bikes with steep seattubes, 0 setback, cleats all the way back to bring knees as far forward as possible, saddle all the way forward. It's still not enough. No one knows why...). Sizing charts and standard knowledge of short torsos puts me on a small. For me, I need the steepest, longest seat tube possible. Those low standovers give me too much exposed seat tube and saddle to bar drop.

 

[KidConejo]

What about seat tube angle? That can effect reach quite a bit too. I'm inbetween sizes on some bikes. With a smaller frame I may have the seat post at min insertion and it results in a rear weight bias as well as sometimes resulting in a reach that's similar to or even bigger than the next size up. With the larger size the seat post may be inserted all the way and even then it could be too tall so I don't get full drop. Weight is more centered. Also changing stems length adversely effects turn in speed, stability at speed and even how much you weigh the front end.

With all the varying geo you have to find a size that's a good starting point then decide what compromises you'll endure to make the bike fit properly. These changes adversely effect how the bike behaves hence why you can see so many varying reviews on the same bike.

 

[Rency]

I am 5'9" with 35" inseam. Crazy long legs and short torso. I believe I have short arms because whenever I try a bike with a ETT slightly under 24" it feels good reach wise.

How should I measure my arm length ? From what point to what point?

 

[Ryder1]

6'2"
36.5" bike inseam
24" torso (as I recall)
Unremarkable arms/shoulders
Can't stand a steep seat tube angle

I look for bikes with short Reach vs. Stack (less common every day)
L Pivot 429T
L 2011 Kona Unit

 

[Ryder1]

I am 5'9" with 35" inseam. Crazy long legs and short torso. I believe I have short arms because whenever I try a bike with a ETT slightly under 24" it feels good reach wise.

Yeah, that is severe (as you know). What bikes have fit you well?

How should I measure my arm length ? From what point to what point?

I believe arms are measured in different ways as determined by the person/system using the measurements.

 

[Rency]

I finally got a scott scale medium. Of course the seatpost is all the way up to the minimum insert line. It came with a 80 mm stem and I think I can still go a little shorter stem. I am going to ride it for a few days before deciding on the stem.

Thanks

 

[Dr Evil]

5' 3 1/2" with a 30" inseam. Recently bought a 2017 Fuel EX-8 27.5+ with a 17.5 frame. While just going by height I would most likely be a 15.5 frame but the LBS recommended based on my body and riding ability to bump up to the 17.5 frame. They felt I would be a bit cramped on the small. The frame just touches me when standing flat footed but I never really stand that way anyway. I always have a slight lean with stand over. After my first 15 mile ride I am very glad I listened to them. Definitely not too much bike for me to handle. Only negative is the 100mm dropper when inserted all the way into the seat tube and fully extended is a wee bit too high for me. It really isn't much of an issue though. I just fully extend the post and then sit to let it drop down slightly to lower it just enough for pedaling.

 

[alexchung]

Interesting thread. I am:

Height - 5' 10"/178cm
Inseam - 30"/77cm
Torso (hip to C7) - 22"/55cm
Armspan - 71"/180cm

(quite hard to measure armspan and torso by yourself though, still need to get full torso but have been told that I am mostly upper body)
Have always been in between for bikes due to my longer arms and slightly longer and torso and currently riding a Large Ibis Mojo HD3. Had a car park test of the new Whyte S150 in Large (Reach of 474.5mm) It felt and looked ok and at no point did I feel outstretched. My problem was always finding something that was roomy enough but didn't need a crane to enable me to get on the bike.
Alex