George

I'm trying to compare frames and I was wondering if 631 tubing is better than 4130. I read where the newer tubing, 631, 831, etc, is suppose to be stronger and give a better ride. I just canceled my order for the LHT, because I read where the 631 may be better tubing and that what I have on my Jamis Coda Elite. I'm starting to think more about the Cannondale T800. Any information would surely be appreciated, thanks George

skinny

631 may be somewhat stronger than standard cro-mo(4130). It depends on the specific application and construction techniques. The published strengths for 631 are moderately stronger than regular 4130. Here is a listing of tubesets with some of the more important specs. Both are good materials and in the hands of a competent manufacturer, both can build into fine frames.

https://www.strongframes.com/material_tech/specs/

George

I'm trying to compare the LHT with my Jamis Coda Elite and the Cannondale T800, thanks again.

bbattle

https://www.worldclasscycles.com/reynolds_631.htm

Chrome moly which in its generic state should carry a SAE/AISI number 4130 will in the best case scenario have a tensile strength of 80,000 psi., before welding.

gcl8a

The steel is stronger, but is the tubing? In other words, do they make the tubing thinner, enough so that the overall tube isn't really any stronger?

Something I've been wondering about.

bbattle

How strong do you need the tubing to be? The newer steels are stronger, lighter, better.

But 4130 is not a bad steel at all. Ride the bike. If you like it, buy it.

bongo_x

I had Carl Strong build me a frame and I just told him what I wanted and let him figure it out.

That's why I'm paying an expert, why would I want to second guess him?

bb

Nessism

This is the Framebuilders forum, people here are interested in discussing the differences in things like frame tubing. Nothing wrong with trusting someone like Carl Strong, but other people want to understand the ins and outs themselves.

bongo_x

sorry, I didn't mean that to be offensive.

alanbikehouston

Among the various "good" grades of steel tubes, including 4130, the issue is not "best", but "best for what"?

A very well made 4130 frame will be a pound or two heavier than a frame made from the most exotic steel tubes. So, you will be pushing 214 pounds of cyclist and bike up that hill, instead of 210 pounds. But, a 4130 frame or fork can be realigned after a crash, and takes normal day to day abuse well.

A guy at a bike shop was showing me one of the lightest steel frame bikes I've ever seen. It was designed for racing, and was super-light. It had a dent the size of a fingertip on the top tube. I asked the owner how he got the dent...he reached over and pushed his finger into the top tube...now there was a second dent...the tube was paper thin.

And, most of the ultra-light weight steel tubes can NOT be safely realigned after a crash. Reynolds warns that "cold setting" its lightest tube sets to correct alignment problems can lead to tube failure.

The charts comparing strengths of various steel tubing are misleading in one respect. The comparisons assume that an equal weight of steel is used for each tube. So, according to the charts, a six pound frame made from "ultra steel" is almost three times stronger than a six pound frame made from 4130.

But, "ultra-steel" is used to make 2 1/2 pound frames, not six pound frames. Assuming the bikes are built with equal skill, and the tubes are properly joined, the six pound frame of 4130 will actually have "real world" strength equal to, or greater than the 2 1/2 pound "ultra steel frame. Plus, the 4130 frame will resist dents, and can be easily realigned as needed.

After all of the arguments about tube strength, the number of documented cases where a properly built frame made with 4130 steel had a tube fail "from lack of strength" is zero...that steel is far,far stronger than the stresses of normal riding require.

So, you plan to enter the Tour de France? Get exotic steel. But, if you are going on a six month tour, or you are a bike messenger who bangs his bike around, the "best" steel for the job may be the old classic steels, including 4130.

Six jours

I really agree with what Alan has written. I think the modern superstrength steels should be considered specialty items, compared to standard 4130. The only thing you gain with the fancy stuff is lighter weight. Strength, reliability and, IMO, ride all deteriorate with the fancier stuff -- and you still won't be able to match carbon in the weight department. Moreover, depending upon your body weight, the specialty steels may not be as good for you as the standard stuff. At 180 pounds, I personally don't care for the flexibility of specialty steels in standard diameters. Oversized specialty steel fixes that, but then takes away from the ride quality. I'll gladly put up with the extra couple of pounds to get a frame that feels just right. YMM, of course, V.

George

After all is said and done, I went out and bought a Specialized Roubaix Elite triple. I thought it was a pretty good price and I got tired of looking for a steel frame at a decent price. Thanks for all the replys guys and safe riding to you all.

maddog17

what's considered a "reasonable price"? for what you need to do is what you should pay. in other words, if your planning on being an elite racer, then maybe spending $3000 on a steel frameset isn't all that bad. if you need something cheaper because your a weekend warrior, then is $1000 or more worth it? is this your last bike purchase or do you like to change rides say every 2 yrs? did you look at Gios at all? last i looked you could get brand new frame with chrome steel fork for under $1000. finding deals on steel frames is getting tough and those used on ebay are pricey.