Jimbojo

Guys, great new forum and great timing. I am heading to the bike shop today to pick up the new hybrid I just ordered but I do have some reservations. I am a noob to biking, but did as much research as I could looking for a decent bike to fit our budget (my wife and I are both getting bikes) of around $400 each. My biggest concern is frame size. I am 5' 8" but my inseam is less than 28", I weigh about 230 and have a long torso. When I straddle even a small frame (17") there is some issues with comfort (soft parts gettin crowded) So I did find a bike that came in xs (15") and the bike shop guys are saying this looks right for me. I guess I am just self concious because this hybrid looks more like a BMX frame and I do think I need to push the seat back a bit, but over all it rides fine. Would it be better to go with a 17" frame for more roomieness in the riding posture. I can deal with the crowding if needed? Any one else have similar issues or concerns?

Jimbo

sreten

Hi,

I'm your height mororless with a 28" inseam for trousers not bikes,
(28" for bikes and 5'8" is seriously long torso short leg territory)
and cannot understand the tiny frame sizes you are quoting.

Bike size is fundamentally relate to height, not leg length, your
a classic case in point, going on leg length most bikes would
be far too cramped front to back, but i don't understand your
"soft parts" issues and what that has to with proper bike size.

rgds, sreten.

Good cycling shorts keep your bits out of the way.

kenji666

DX-MAN

Unless you KNOW and TRUST them, shop guys' advice should always 'be salty'....... But you say the bike fits and works fine. So DAMN what it LOOKS like, bikes are for riding. You'll LOOK a lot worse out on the road somewhere, unable to ride any further because poor fit has worn you out or blown out a knee.

loneviking61

I feel your pain! I'm 5'11" with a 30" inseam. My LBS says to go with the right frame size for your height and leg length. And then, for the torso, put on a different stem (for height) and change the stem angle to fit you. I have an old 10 speed and a taller stem made a huge difference in comfort. Find a shop with a good reputation for fittings and get a fitting done.

Road Fan

Jim (if I may be so familiar!), firstly, how did you measure your inseam? It's not your trouser length. My trouser length is 29" or just under 74 centimeters for trousers I would wear to the office, but my cycling inseam is 81.4 centimeters. If you are doing any calculations, it makes a big difference. In my case, the addition is 77 millimeters, or 3.0 inches! We can take that as a rough rule of thumb.

I can understand the desire for zero contact with your soft parts. For my own riding I am less concerned about that. There is a sizing (not fitting!) characteristic called standover height (SOH). It is the actual vertical distance from the top of the top tube to the ground, with the tires fully inflated. For a sloping top tube, measure it at the midpoint of the top tube. You can see that if this number is too big, you'll have undesired contact. If it is too small, the frame will actually be too small, probably with not enough top tube length or the seat tube may be too upright. For me, zero contact is when the SOH is less than about 76 cm. It also matters whether I am wearing bike shorts or not. But my bikes range from 77 cm to 80 cm in SOH, so it's not universally important.

If you can go and measure the SOH of your bike, let me know. More later!

Road Fan

fietsbob

Think of a fork substitution so its tall , full length of Steel, steerer , lots of spacers that will get the bars Up,
and then you can sort out the reach with various stem lengths.

jyl

Can you post the brand and model of the bike you are looking at?

And measure your bike inseam?

The problem with getting a XS (15") bike to accommodate your short legs, is that the top tube will be sized for someone who is 5' 2" or thereabouts, but you probably have the torso of a 6' 0" person (I'm sure to be not exactly right with these numbers but you get the idea). The result will be that you will be cramped and forced to ride in a very upright position.

Novices like a upright position, but if you move beyond novice rider and short slow rides, a very upright position will be a disadvantage. It is a weak pedaling position; to best use the big muscles of your glute/butt, you want to be leaned forward, with a larger angle between upper leg and torso. It creates lot of aerodynamic drag; above about 15 mph speed (or with a headwind) air resistance is the biggest thing draining your energy. It concentrates weight on your rear end; on longer rides, saddle pain is more likely.

You should buy a bike that:

(1) you can stand over, both feet flat on the ground, with at least 1" clearance between the top tube and your pubic bone - the soft bits can touch, but you don't want to hit bone - AND
-

(2) gives you enough room from saddle to handlebar - as a rule of thumb, when seated on the bike, look down at the front axle, the handlebars should appear to be "in line" with the front axle or "forward" of it.

(3) has your torso leaned forward at least 30 degrees from vertical, as much as 45 degrees - basically the faster you go, the more lean you will want.

If you plan to only ride slowly, on flat ground, for shorter distances, then (3) is optional. (Of course, in that situation, bike fit isn't all that important.)

This may possibly mean not getting a traditional diamond frame bike with a top tube. You may end up on a mixte type frame, which is traditionally found on a "town" or "city" type bike. One make that has a lot of these is
https://www.linusbike.com/models/

Your bike shop may not have such bikes, and thus try to steer you to the 15" bike simply to make the sale. Sad to say, some bike shops are no better than car dealers in this regard. Don't let that happen.

trainchaser

...let me jump in here with some recent experience, I have the exact same measurements, 5'8" with 28" inseam - measured properly, not by pant size, so I know what you're going through. The suggestion of looking for something along the lines if the Linus Mixte is similar in concept to I ended up getting. I ended up with a hybrid that features a sloping top tube that gives you adequate stand over height. Almost all makers have bikes similar to that, so take a look at the frame geometry specs of the various offerings and see which one will work for you. My choice after checking them out was a Specialized Crosstrail with a medium size frame...

Kidballistic

Not sure what my inseam is, but at 5'7" I know I am a little bit on the short leg and longer torso end of things. This usually just gives me troubles with fitting on a vintage road bike. I can ride anything from a 50cm bike to a 54cm bike. Of course the right height bike is a 51 for me but I need a top tube of 53.5... A vintage road bike that is a 53 gets me in the junk pretty solidly. Anyhow, on a mountain bike a 16 seems to work best, and I can deal with a 17 if I have to. If you are 5'8" and they are trying to sell you a 15 that does seem a bit extreme to me. I would say go for a 16 or 17 and just deal with it. A 15 is a really small bike.

Jimbojo

So, I will need to get some erasure nets but, I do know that straddling a 16 or 17 inch hybrid frame with 700c wheels is not comfortable. The XS frame I got gives me about an inch or two of clearance when flat footed. Now I did go back and have the shop fit check me, my seat was fine giving roper leg room and using a plumb bob he said my seat position was right for correct peddling. But my position was just a bit more upright than might be optimum on a comfort hybrid, so we put on an extended stem. The riding position doesn't seam bad and I am not experiencing back pain s I think I am fit fairly well to this bike.

Jimbo

digibud

5'8" and you're looking at an XS frame?? that's quite something, but if you have a longer stem on it and it feels comfortable, that's all that really matters. You may find in a year or two, after a ride here and there on some other bikes, that another size/make/model fits even better. MANY people end up on bikes that don't fit perfectly. Reasonable and OK is about all most of us can expect from the average decent bike shop.

Jimbojo

Ok, my bike is a GT Transeo and I made a few measurements, first, not sure how to measure a bike inseam, but from the ground to my hip bone is about 31 inches or so. Now the SOH on this frame is 28" when I stand over it I have about an inch and a half to two inches before the frame hits bone. On my wife's Fuji Absolute (17") If I sand over I am basically hitting bone. But from the stem to the seat post is the same on my bike as my wife's so I am not sure the comments on this being smaller is universally true. I also drew a line from hip to shoulder, when on the bike, measured a bit over 30 deg, after the new stem. At this point not sure I can do much better, I did find one 16" bike that would work too, but I didn't like the ride as much as the Transeo.

Stan A

That's a Transeo?. I also have Transeo but the top tube is much straighter and more horizontal. Is that how they get it to be an XS?

chaadster

Jimbo, if you'd like to get your back flatter, you could try flipping the stem, so that it angles down.

Jimbojo

Yeah, I think they do it with bent top tuber to maintain the triple triangle design.

Jimbojo

Yeah, that would be my next step, but I'll probably ride it like it s for now. Our guy was saying as new riders we would probably feel more comfortable a bit mor upright, but as we got more confident we would want to lower our riding position.

Jimbojo

So, after another short ride (7 miles) I am more convinced that the frame is a bit small for me, I do have it set up to fit me, but it is at the extreme, with and added longer stem. So partially based on fit and more so based on some function concerns, I am leaning towards swapping my Transeo for one of these https://www.performancebike.com/bikes...400784__400784 Fuji Absolute 3.0 in a 17" frame size. It comes with an adjustable stem so I can set the bars more aggresively as I gain confidence. The SOH is probably at my limit, but with bike shorts on, nothing is getting smashed, and I can lift the tire an inch or so before it hits bone.

Jimbo

Road Fan

Jim, your standover height is probably just fine as it is.

I'd like to still suggest you measure your inseam, but we haven't told you how to do it. Generally the method is as follows:

1. Collect the stuff you will need: an assistant, a tape measure or yardstick that reads in millimeters or in sixteenths of an inch (yes, it needs to be precise!), and a large book 1" thick or a small stack of vinyl record albums.

2. stand barefoot on a hard floor with your back against a wall.
3. take a large book about 1" thick and pull it up into your crotch as hard as you can. It needs to stay square against the wall.
4. While you are pulling the book up hard, have your assistant measure the vertical distance from the top of the book to the floor.
5. Read the ruler carefully and write down the number.
6. Repeat two more times. The correct number is the largest of the three.

This is your cycling inseam, or pubic bone height. It's the actual length of your leg from where your pelvis puts weight on the saddle to the bottom of your heel bone. You can see this number is different from trouser inseam and from the hip bone height. You can use this to find a starting point for saddle height. We've been talking a lot about frame sizing, but this is the start of bicycle fitting.

Multiply your cycling inseam by 0.883 to "Greg LeMond" height. Write it down. That number should be the distance from the center of the bottom bracket, or crank spindle, to the top of the saddle measuring along the seat tube. For a lot of people this is the correct saddle height, and it's a good starting point for just about anyone, since it's reproducible. There's a minor variation due to crank length, but let's just handle that later.

This saddle setting should be safe for your knees, give you decent power and spin capability, and let you start fine-tunign your lean from a solid basis. The saddle height is the most important thing, since it affects your knee health.

Jimbojo

I will do this, I did trade in the Transeo for the Fuji Absolute, setting the seat height correctly will be a great start.

Jimbo

Road Fan

What's the standover of the Fuji?

Jimbojo

Fuji SOH is 30.5", my inseam as measured by your directions is 31.625", so i get 27.92" using the multiplier you gave.

Road Fan

Your inseam in centimeters is 80.33, and your saddle height target is 70.9 cm. Set your saddle at that height, set the tilt level using a level if you have one, and go ride and tell us how it works and feels. We still have to work through saddle fore/aft positioning and tilt.

Jimbojo

Cool, will do first thing tomorrow, I think I have it a bit short right now.

Road Fan

When you pedal-stroke downward, your feet should not feel like you're pressing through the pedal, at bottom.