TallRider

Hey, I'm 6'5" and have been riding a 61cm (59cm top tube) frame that's significantly too small for me, and will probably sell it to a friend and am planning to buy a Soma Smoothie ES as replacement. The 66cm frame. I like the design, with standard-reach brakes so room for larger tires and fenders, and I like the "road sport" geometry and I like the fact that it comes in 66cm with a 62cm top tube. My only worry is this: will the frame be whippy or flexy? Very large frames have some danger of this, and front wheel shimmy while riding no-handed, etc. On these counts, I've been spoiled by riding an aluminum frame that's a bit on the small side for me - it's plenty stuff, not whippy, etc.

Does anyone have a sense of how an extra-large frame built with Reynolds 631 (welded) will be on stiffness/whippiness? I don't need it to be a rock-solid sprinter, since I usually just go for country-road rides, albeit fast ones. But I don't want it to be a noodle, either. Thanks.

alanbikehouston

Contact the people at Soma and ask them. A steel framed bike rides exactly how the designer wants it to ride.


For example: Back in the 70's, Schwinn asked Reynolds to make a special 531 top tube with thicker walls than other builders were using. And, Schwinn used straight gauge, not butted tubes for the downtube of a Paramount of size 60 or larger. The result was a stiffer (but heavier) bike. Schwinn knew from its research and testing program that a 25 pound bike could be ridden as fast as a 22 pound bike, if the wheels, tires, and components were of similar weight and quality. And, Schwinn knew that muscular 250 pound riders could flex the downtube and bottom bracket on a frame that was "perfect" for a bony 130 pound rider. So, they designed a size 60 frame that was very different than their size 54 frame, and their size 54 frame was stiffer than those built by the "lighter is everything" bunch of knuckleheads.

thewalrus

when a problem comes along... you must whip it

whip it good

Thylacine

This is just a philospohy thing, Tim. There hasn't been a paper published on the detrimental effects of frame flex. In fact, it can be easily argued that the basic inefficiency of the human machine pedalling a bike wastes more energy pedalling inefficiently than is wasted in .2 of a millimetre in frame flex.

You also don't mention how heavy/strong you are. I'm 6ft 4ins and 200lbs and ride a steel bike and enjoy the ride. Sure, it's not as stiff as Aluminium but philospohically it doesn't worry me.

From a geometry perspective, the Soma isn't bad. I'd want to see you using a layback post though, as 72.5 degrees is a little on the steep side for us big guys. The layback with the long stays would work well.

Back to stiffness, on the Soma, it will depend a lot on the diameters of the tubing. If they use the same diameter tubing on every size (I suspect they do), then the Smoothie in a 66cm will be quite flexible. For a guy your size I'd be looking at a 31.8mm seat tube, a big down tube (34.9 would probably not yield the stiffness you'd be after) and I just don't think the Soma will be optimised in that regard.

That's the problem with us big guys - off-the-shelf just doesn't work out to be as good as a frame with custom spec'd tubing.

roadgator

like alan said it will depend to an extent on the tubeset used, but ingeneral a large steel frame will be more flexible than a smaller aluminum one.

i ride a large steel frame myself (late 70's takara lugged touring frame. 62cm seat, 57cm top tubes, pretty sure its butted chro-mo, but not posative) it has pretty relaxed geometry so im not sure how that would compare to "road sport" geometry.
it does flex noticably when sprinting (im 180lbs) especialy compared to my 56 cm CAAD 5. it is very comfortable and smooth over bumps and lumps in the road.

however it is INCREDEBLY stable riding no handed. i can hit speed humps and potholes cruising along without my hands on the bars and it all just gets soaked up and the momentum keeps rolling forward. deffinetly not the case with my cannondale. i havent done any high speed descending on it but it feels stable and predictable (allbeit a little slugish) up 30 mph or so. take this with a grain of salt since, the takara has much heavier wheels and a lot of rake in the fork which will tend to make the handling feel slower/more stable already.

your bike could be completley different, but i thought id at least give you my comparison. if you dont mind giving up a little speed in the sprints i think steel has more pros than cons especaily if you are going for higher miles or rough surfaces.

was_bmxer

I'm 6 foot 5 inches and rode a lemond, reynolds 853 zurich. Had it for about 2 years. I found it a very smooth bike to ride, on long rides it was great. Soaked up the rough stuff really well, very stable down hill (much to do with the geometry). Now I ride ALU race bike, for over 3 years now and it's a bit of a punisher, very good for racing, crits usually.

The down side of the lemond was infact the head shake, sprinting was scary as it was a full on wet noodle. You could sit at lights with the back brake on and flex the seat stays back and forth, used to freak peolpe out a bit. Riding in pacelines in the big ring, it would always scrape, likewise uphill. the flex from around the BB was not that noticable, the sound was very annoying. Could not fine tune it out. I have a mid 90's lugged steel pinnarello now and it's comfy as could be, flexy too.

Good luck with what you get, as mentioned above, for us big chaps custom is the best option.

biker7

I ride a 61cm 631 Reynolds bike. One man's whippy is another's just right. Typically there is a correlation between whippiness and ride quality. Stiff generally is not a comfortable but better for energy transfer. Would say my bike has medium flex...not too stiff and not too flexy. It sprints fine but I can feel the flex. I like it. Frame designers as mentioned by Allan tyically adjust frame properties...wall thickness or tubing O.D. to gain section modulus to increase stiffness lost by longer beam length. Bigger bikes are typically ridden by heavier riders and this is factored in as well. You can contact the manufacturer but all you will get is a marketing or a qualitative response that will have little value to you. You will have to ride it to know for sure. Some good players like to play with a soft shaft in their driver and some like to string their tennis racket's loose. Bike stiffness preference is no different. I don't like an overly stiff frame and others love 'em rock solid.
HTH,
George

EURO

My winter ride is a 60cm (58 top tube) Oria tubed steel bike with a steel fork. It's flexy as hell, and weighs a ton. It's not even that comfortable!

If you are just doing country road rides, then none of this will bother you.

BryanW

Yeah, I've always been surprised by people saying how comfortable steel is. Not my (limited) experience. My last steel bike was very flexy side-to-side (I'm 6'3), but a pretty harsh ride too. One thing I found about it was that climbing and sprinting out of the saddle, it just didn't feel as smooth and natural as I thought it should (or like my friends looked on their alu bikes). Then I got my current ti/carbon bike, which is much stiffer (and more comfortable), and the difference out of the saddle was incredible, not just in terms of efficiency, but the ability to get into and hold a smooth rhythm. However much or little energy you lose in flex with steel, in my case at least the way it flexed stopped me feeling "right" on the bike.

Of course it probably wasn't a good steel bike.

TallRider

I'm 6'5", 185#. Pretty powerful rider sprinting or climbing out of the saddle, but I don't do either that often. Given that I'm mainly out doing country-road rides.
I'm fine with a bit of frame flex (though the story about the 853 LeMond doesn't sound pleasant), and realize that it's a trade-off for comfort, etc. But if I can't ride no-handed safely on this thing, the deal is off. I've got an old steel bike from 1981, that's *really* flexy, and with a long head-tube and all, the front wheel can get a lot of shimmy when riding no-handed.

biker7

Its bike specific in terms of how each big framed steel bike will flex and track. My latest steel Bianchi has a 200mm head tube and carbon fork and tracks like a slot car. In fact, I have never ridden a bike I can lay over at 25 mph at full crank when powering through a turn, hit a small rock and the bike doesn't lose its line...part of that being wheels. Have descended at 45 mph on the thing and it is dead rock solid.
Again, this bike is not that stiff when sprinting so one can't completely correlate stiffness with handling. No problem going no handed either.
George

53-11_alltheway

I think this whole aluminum is more uncomfortable than steel thing is just BS.

LOL, the myths that get perpetuated in cycling never cease to amaze me.

TallRider

The extra-large ExtraSmoothie has 66cm seat tube, 62cm top tube (ctc) and 25cm head tube. My current bike has a 17cm head tube! So, it'll be substantially easier to get my handlebars up - they were 5 inches below the saddle, and since I don't race I'd prefer them much higher.
The other option is to just get a Nitto Technomic stem, which would could get the handlebars 6cm higher.

sydney

Running 160 cranks to keep from catching a pedal on the pavement?

biker7

A little pedal scuff never stops me..lol. Bang my pedals on the ground all the time through turns.

George

EURO

But steel is older than Alum. Anything that's older is nicer. You know, real ale, organic vegetables, leather shoes, quaint english houses, Shakespeare, vintage cars, Jazz, slavery...

Don't crush the dreams of the middle-class people! Technology is ruining everything! I want a gas-lit house and bubonic plague!

biker7

A philosophy question then for you then 53...do you think that stereotypes by and large are true?
If not, how do they become stereotypes?
George
P.S...flipside is...it never ceases to amaze me how those that ride Aluminum and love it are deluded into believing any aluminum frame has as good a ride quality as steel.

TallRider

More of a social-science question. But yeah, most stereotypes have a basis in fact, and some are straight-up fact. In the absence of any other information, a black kid in Cleveland is more likely to be able to sprint fast than a white kid in Cleveland.
Also, a well-built aluminum frame (that won't fail from flexing as aluminum is prone to do if it's not stiff enough) will tend to be less comfortable than a well-built steel frame, though a builder working with steel has more choice on the ride characteristics of the design than aluminum.
Of course, we could all ride old Vitus frames...

sydney

Sean Kelly did pretty well on them. There is a guy I see on a regular basis,built like a pro(Richard Virenque like) that sure doesn't give up anything on a steep climb on his.

hiracer

I can watch my BB move on the trainer with moderate-to-high resistance. Lemond Sarth 61cm. I'm not a strong rider. 6'1.5" 195 lbs. TT Platinum OS steel.

But the bike is solid at 40 mph.

I could ride a 59cm frame, but for the fact that I'm not young anymore and I prefer the bars 3/4 inch below the saddle--and I got long legs, ergo, high saddle.

Not sure what this tells you. You can get a custom steel frame that addresses your issues for under $1,000. I'm giving it serious thought. Best route to go for someone like you.

TallRider

I'd prefer running larger tires (28c, eventually perhaps 32c) which is very effective suspension at 60-70 psi. And I can't run larger than 26c tires on my current bike because of short-reach brakes in which the pads aren't close to their full extension.

I'm thinking seriously about going with a Curtlo frame. I'd prefer longer chainstays, in case I want to do touring and for the ride quality (other than stiffness factor), design it for standard-reach caliper brakes, lowered angled top tube with long seatpost... with steel fork for $905.

John Wilke

Why do you need a larger frame? Can't stretch your legs out? I'm also 6'5" and have been riding 61cm frames for the last 20 years ... I use MTB seat posts to get the saddle where it needs to be. Looks goofy to others, but works great for me.

John Wilke
Milwaukee

Treespeed

That's a big jump, from a 61 to a 66. I'm 6' 4" and use a 60cm. I just picked up a Surly Pacer and it is so smooth. A little on the heavy side, but it has braze-ons for racks and fenders, plus clearance for wider tires. Just an option if you want to save a little money.
I built mine up for about $1000. Good luck with whatever you decide on.

TallRider

Main reason for a larger frame, honestly, is to be able to get the handlebars higher if I want to. Currently they are 5" below the saddle, and I've got a stem that angles upwards, at full extension from the steerer tube too (it's a quill stem). I recently bought a Nitto Technomic stem that rises a lot, and may just install that on my current bike and be done with it. But I'd also like to have extra room for larger tires, a bit longer wheelbase, and a longer top tube, so there are other reasons for getting a new frame.
The Soma ExtraSmoothie is about the same price as the Surly Pacer, both much cheaper than a Curtlo custom (which would still be very nice, though).

DannoXYZ 

Aside from the factors he's already given, a properly-sized frame will also allow you to be more aero. You can ride with a flatter back and not be all hunched over. Lower back pain, and open chest for better breathing. You can put your hands in the drops with your forearms parallel to the ground so that they block only as much wind as your hand. A long-enough top-tube allows you to do this without having your elbows hit your thighs, or else you'll have to stick them out sideways and negate any benefits of getting low and aero to begin with.