Tony (Michigan)

My Pubic Bone Height is 35" or 88.9 cm
Subtract 10 cm and get 78.9 cm for saddle height.
Subtract 15 from 78.9 and get 63 to 64 size bike.

Wow!

What do you think? I would think I'd be too stretched forward, wouldn't you?

stapfam

Time for Maddmax to post his Sizing measurements. I didn't use his system for my bikes- but it was spot on.

Longfemur

Keep in mind that Rivendell bikes kind of assume you will ride with high handlebars. That brings them back and so shortens the reach a bit. They also suggest that their bottom brackets are lower. I don't know, I've never measured one, but assuming that's true, it would mean you could get the same standover clearance as you normally would on a slightly smaller frame. Personally, if it was me, and I was in that position once, I would stick with the inside leg measurement (same as "inseam" or "pubic bone height"), and multiply it by .065 (centre-to-centre frame sizing, or the equivalent for centre-to-top), unless you actually are buying a Rivendell and you want high handlebars. Also keep in mind that that kind of bike rides more towards the touring bike end of the spectrum than the racing bike end. So it depends what you want. Just because you're over 50 doesn't mean you can't appreciate the ride of a fine road bike set up moderately racing style. There was a time when I was approachig 50 that I assumed I would be more comfortable higher and more laid-back and with fatter tires, but it turned out I really missed the racing bike feel (fast curves, fast downhills). Maybe when I'm 60, I'll get the bars back up, but not right now.

maddmaxx 

On cue:

Basic bike size=.67 times your true inseam height (use book pushed up there uncomfortably for measurement guide against wall, measure to top of book)

Top tube length modifier is a ratio of overall height divided by true inseam height. If it is greater than 2.2 then a longer top tube (maybe larger bike) is indicated. If it is less than 2.0 then a shorter top tube (smaller bike?) is indicated. This measurement corrects for long or short legs/short or long torso.

These are approximate starting points as different styles of bikes vary in their frame dimension ratios and riders have differing tastes.

I think for Tony it worked out to 57/58 for a basic size with a modifier toward a shorter bike. I believe that he got and likes a 55/56.

solveg

My PBH is 81. My Atlantis is a 56 cm. It's a good fit for the torso, but pretty high in the top tube, but I don't really care. If I was a guy I'd care more. But I'm long waisted, so what's a good stretch for me might not be for you. I don't know how anyone* can ride a bike based on the seat tube measurement unless you have a very normal body type.

And Rivendell, who prides itself on being rational about bikes, measures by the seat tube. What difference does that make to the ride? FWI, the bottom bracket is low on my Atlantis.

Tony (Michigan)

This is what is so nice about this site. . . . great people taking the time to help others. Thanks for all of your help. When I tried a Giant tr pro or whatever it was (carbon) it was a 58 and I felt like I was stretched out too far to the horns. But maybe I was not just broken into it having gone from my 53.5 trek to that.

Well, this should end my curiosity about if I should have gotten a bigger bike.

Tonight I go into the Trek store with my bike and they are going to fit me out and do all the fancy shmancy adjustments so I will be a little faster than that guy whose last name is Armstrong (nyuk nyuk nyuk!). (In my dreams).

Thanks again folks!

Tony

BluesDawg

Keep in mind that Rivendell's sizing recommendations are for Rivendell bikes. Their 63 may not be dimensioned similar to other makers. Grant's sizing philosophy leans toward fitting riders on the tallest frame possible and working with bar height and stem length to work out the reach. I would not think of using Riv suggestions for another brand, but I would think hard about going against their recommendations on one of their bikes.

George

If you went by Rivendell's measurements you would have to buy there bike, because hardly anybody makes them that big.

It would probably be a good idea to go to a bike shop and try some bikes on for size. You may be surprised that you can fit on a 60cm, with no problem.

Tony (Michigan)

O.K. I went to the Trek fitting thing tonight and the guy there, after measuring me and running everything through their computer told me I should be on a 58 road bike. However, he said that LeMond Poprad is different and that my 55 is O.K. for me.
He was very good and adjusted some of my teckniques, seat height, etc. It was a good experience.

Tony

solveg

OK, I don't mean to start trouble here, but being of normal size I really don't know the answer to this. How many 60-64 cm bikes do they stock at an LBS? Would they tell him that he needed a special order frame, or just try to make one that they had work?

Tom Bombadil

Depends on the LBS. A reputable LBS would advise a buyer to get the right sized bike, even if it isn't in stock. I've known LBS's that wouldn't hesitate to do that.

But there are certainly many that will push whatever it is that they have to sell.

Tom Bombadil

While it is true that one can adjust a bike to achieve a better fit, and that expertise in this area can be very helpful, I'm not buying the statement that the Poprad is different, because it isn't.

The LeMond Poprad is a typical traditional geometry bike. It is true that their sizing is a bit smaller than what Trek uses on their other lines ... that is, a 55cm Lemond is essentially the size as a 56cm Trek.

Consider the effectively length of the top tube: A 55cm Poprad is 56.1cm, a 56cm Trek 1500 is 55.7cm, likewise for a 56cm Madone. A 56cm Trek Portland has a TT of 56.5cm.

Meanwhile a 58cm Trek 1500 is 57.2cm and a 58cm Trek Portland is 57.5cm

Thus one can make the case that a 55cm Poprad is the equivalent of a 56cm Trek. But it is smaller than a 58cm Trek. If your perfect fit road bike is a 58cm, then it goes that your perfect fit Poprad would be the 57cm size.

But that doesn't mean you would like the 57 better. Some people like a bike that is a bit larger or smaller than the formula suggests. However I think the LBS should try to put you on the best fit first and do their best to make that work, rather than put you on a less optimal fit and then make adjustments.

Louis

FWIW, all my bikes are not dialed in to one exact specification, they're close, but all feel slightly different. When I switch bikes occasionally, the "new" bike feels weird for the first few miles but not uncomfortable. I've done long rides on all of them with no problems. Perhaps I am lucky that my body seems to conform to a number of slightly different adjustments, or I'm such a fred that nothing matters.

Tony (Michigan)

56 cm = 22 inches
58 cm = 22.8 inches

I wonder if it makes all that much difference to push the steering tube about 1/2 to 3/4 inch further from the seat to attain the 58 cm distance as opposed to my current bike size?

I know I'd be reaching further. Would reaching 1/2 to 3/4 inch further be as comfortable for 100 miles than what I am now? I don't know. I just don't know.

I did ride a 58cm Giant and the reach did not feel as comfortable to me as the LeMond. But maybe it all comes down to getting used to a longer frame and bypassing the discomfort for a couple hundred miles?

LastPlace

Against the advice of my LBS I did exactly that, and bought a 56cm Soma instead of a 54cm model.

It is a great bike but too large and I have had trouble getting it to fit.

Having learned an expensive lesson I will always take any potential new ride for a looooong ride.............

big john

I have a 35" inseam and I ride a 64, a 63, and a 62. All different makers, all different length top tubes. The 64cm frame actually has the shortest top tube of the three. I have long arms, btw.

markf

I sent Rivendell my measurements in 2001, including a 87 cm PBH, they built me a touring frame with a 58 cm seat tube. I don't remember the other measurements, but comfort has never been a problem on that bike, even after some long days in the saddle. I do ride with my bars lower than they advocate, which I told them when we were discussing how to build the bike. My other bikes are a 1988 Marinoni w/ a 57 cm seat tube and a 2001 Marinoni Piuma w/ a 58 cm seat tube, both very comfy. Get in touch with Rivendell and talk to them before you buy a bike based on what their website says. They're not nearly as dogmatic as some people would have you believe.

solveg

Tony, here's something to think about. It takes a while for the muscles in the back to get used to stretching. I don't know about others, but I can ride anything for a little while, but when it gets over 10 miles I start to really need to stretch out a bit. If I had to chose between a bike that was too big and a bike that was too small, I'd chose too big, because I really hate the feeling of being cramped up in that cockpit. I would try some more bikes before you get one that is so much smaller than the numbers add up to. A centimeter doesn't seem big, but you'll feel it on a long ride.

maddmaxx 

For those who want to learn a little more about what sort of stuff goes into a bike fit, here is an article (moderate length and may leave you gasping for air about technical jargon) about fitting a race TT bike for a rider who already knows some very specific knowledge about the measurements of a bike that works for him.

https://www.slowtwitch.com/Bike_Fit/F..._back_290.html

Slowtwitch.com by the way has a whole series of articles on the sizing and fitting of TT bikes. TT fitting is a little more of a science than the average bike shop fit. It is much more akin to fitting a pro racer to a bike. It has the advantage of being in the public domain however (which I doubt is the case for many of the pro teams).

Although its TT related, the science is interesting for those willing to pick through it.

maddmaxx 

By the way, a change from 22 to 22.8" on a top tube is a 3.6% change. That change also effects many other things about the bike including how much weight will be supported by the riders hands. For some manufacturers, the head tube may not change in length resulting in bars that are closer to the ground relative to the saddle on a larger bike. Other manufacturers change the angle of the head or seat tube as the bikes get bigger.

Years ago we used the seat tube length to measure bicycles for "standover height". We are getting a little smarter today as we understand that a proper top tube length is necessary to get a good "reach" for us. Tube angles, head tube length, center-front and center-rear are all dimensions that are part of the "proper fit".

After all of that science, it is the riders perception of fit (or for racers, the stopwatch) that determines what is right.

mandovoodoo

I don't see any problem with their recommendations. Their bikes are essentially refined versions of older regular road bikes from the 1960s & 1970s. Their fit is essentially the "big = comfortable" high bar touring approach from the same time period. The puffing is really great, though!

But it's different from a racing fit, and folks seem to have forgotten how things used to be. Racers with smaller tight frames and regular folks with bigger comfortable bikes. Roads were generally pretty bad compared to today, too. So we always had a 73 parallel light fun bike with Campy NR and tubulars, fit pretty small (55 for me) and a utility touring bike fit bigger (57 perhaps). Now the utility road bikes have generally gone away at the high end, although they're around in the less expensive models. Have to look, many low end models are imitation performance bikes.

From Dave Moulton, I'd run a 55 x 55.25 w/ about a 118 mm stem ideally. TT + stem of about 67 cm. Can think of that as 55 square because todays seat tubes are a little steeper. Another chart of his, 55 has a reach of 67.5 and drop of 8.7. I actually run 54.5 + 12.5 = 67 cm, and 8 cm drop. Which is OK, because my head tube angle is a little shallow, so longer stem shorter TT is the way to go.

My fit by a real master in 1974 gave me 21.5" TT = 54.6 cm and I ran a 100 mm stem. 64.6 cm. Was always a little cramped on that one.

My touring bikes at the time were generally 23" frames, so that would be about 22.5 or a bit less ctc, 57 cm ctc say. TT were probably 57 cm and I'd run a 90 mm stem jacked up level with the saddle, reach of 57+9 = 66. I'd run the saddle back and these were probably 72 parallel frames. I'd set one up and sell it to the first guy who liked it, but they were all about the same. Nice British touring rigs. Bikecenntennial got folks interested in touring and I could do a bike up well, so the market was there. They all rode about the same, too. I'd forget what I was on!

"Rivendell" would put me on (low end of their scale) a 59. I'll look at a Bleriot. 72 x 71 w/ 5 cm rake and WAIT - this is for 650 tires!! Will never do. Let's find a 700C. OK. Homer Hilson, 72 x 72, 59 x 58 with an 85 cm standover. That's WAY up in the air for me! And very far out. Put a 90 mm stem on it and I've got a reach of 67. Hold on, that's just right. I could actually ride that setup! With the bars up high, I'd be tempted to put a 100 or even 110 stem on it.

But would I like a Hilson? It's just a little bitty bit bigger than I used to tour on. The geometry is nice. I bet I'd like it. I think a 58 or larger would just be a bit huge.

But wait, that's about the same geometry I used to tour on, but a little undersquare to get the bars up. And many people used to ride big frames back in the day. Is there really any difference?

Old British touring. 72 square 50 to 55 mm fork rake, 43 cm + chainstays, 57 x 57.

57 cm Hilson: 72 square, 52 cm rake, 45 cm stay, 57 x 57

Hmmm. Nothing new under the sun. Except for fitting perhaps 1 size large to get the bars up and back.

I imagine I could ride a Hilson loaded with bags no hands on the level and put on a jacket.

What would I get from their line?

Looking at geometry, Legolas in 55 appeals. 73 x 72.5, 55 x 55.5, 45 mm rake, 43 cm stay. Quickbeam 56 is a bit slacker in the seat, low and long rear end. That's cool, too. Most of them seem to have reasonable geometry for smooth handling road bikes.

I think the big deal is the way big sizing. Everything else looks like standard dated road bike design - which doesn't feel nearly as dated on the road!

This is fun now. Let's see what they would want to put me on. Two types of riding. First, fast recreational with smooth handling, lots of hills, light loads at the most. Second, mid-weight short tours, commuting, utility. 170 lb for me, 30 for the bike on the first one. Add 30 for the second. So 200 to 230 lbs. Looks like they'd put me on a Hilson. I'll look at it. I like. Wonder if my old Campy sidepulls would fit.


OK, much discussion about very pedestrian, well thought out bikes with lots of puffing. "Big bike = comfortable" - funny, I used to tell people that in 1973 when I was selling bikes! Old stuff in new package. I'd probably compromise and go slightly big, but below rivbike's recommendations.

Would be quite a contrast with my tiny carbon compact, which is very dinky and tight and very Italian, with my bars and saddle out from the center, wheels tucked under. That one screams GO GO GO GO GO all the time. A mellower ride might be fun.

Tony (Michigan)

I just got off the phone with a sales rep from the LBS I purchased my Poprad from. As it turns out I purchased the last Poprad of my type (no disc brakes) the company has. They do have a size 57 which is basically a 57.8cm TT (in disc brakes). But it is at another store and they don't want to ship it to their store where I purchased my bike and take the chance of me not liking the fit.

So they want me to bring my bike down and see if they can either make some adjustments to it or just have me try out a completely different bike.

This is what stinks about a bike shop making me buy a bike first and then going to another store with that bike to be fitted. Had they taken all my measurements first and told me the ideal bike to get I would not have purchased the 55cm Poprad.

Thanks for letting me vent a little. There, now I feel a little better.

Tony (Michigan)

Sorry to keep dragging this through the mud. I spoke with the guy that measured me. He told me the bike I now have fits me very well. He said it is just not meant to be a road bike. It is more of a comfort style. If I were getting an actual road bike then a 58 would be what I would want. He said whether by hapinstance or whatever, my current new bike fits me well and I should be comfortable doing centuries.

Thus ends the saga. It is just that after paying so much for a bike I just want to make sure I am getting exactly what I need.

Tony

Tom Bombadil

You may indeed be comfortable doing centuries on it. However, as much as I hate to say it, the Poprad's design is not a comfort style bike. He is either lying or misinformed.

Take a look at this bike:
https://www.lemondbikes.com/bikes/cross/poprad.php

The head tube is low, the top tube is horizontal. There is no "comfort style" aspect to it, outside of it having a bit of an upturned stem.

FWIW: Last year I test rode a few LeMonds. Two different Trek dealerships told me that my best fit on a Lemond was a 53cm bike. I'm 5' 7.5", my inseam is only 28.25", and my Rivendell pubic bone height is 75.

Tom Bombadil

Hey, are the Poprads on big sales yet at Trek dealerships? As Trek & LeMond are locked in a heated lawsuit, what I've heard from Trek dealers is that they expect the two companies to go their separate ways and thus Trek will be dropping the LeMond bikes, supposedly replacing them by bringing back their Klein line from Japan and Europe.