guadzilla

Hi guys -

Am looking to get a custom steel bike made for my wife, as a general gravel/beater/rain bike (she already has a carbon road bike and will likely add a S-Works Tarmac when the new SL7s come out).

I am toying between these 3 options as a choice of frame materials - yeah, its a pretty wide range, I know. Given the use case, I dont want to spend more than I have to, but obviously, if spending a little more gets me better performance, I am happy to do so.

There's about a $500 jump in frameset price when i go from double-butted 4130 chromoly to 631, and from 631 to 853. There's also a weight reduction of approx 200gm and 400gm with each step up.

Leaving aside the question of weight, any opinions on whether the ride quality would be significantly different? As mentioned, this is going to be training/exploring/general riding bike, likely clad with 700x32 rubber - she has other bikes for racing or going fast. Also, while she is a pretty strong rider at almost 3.5W/kg, she's under 110lb and isnt exactly putting out megawatts. So looking for something that is smooth but also not an absolute pig to ride.

Yes, I am aware that other factors also play a role - am just looking for an indicative sense of what the sweet spot for price/performance might be, in terms of choosing materials for a bike with this intended usage. If the 853 is going to be a noticeably more fun ride, i will spring for that. If the difference is mainly weight but the ride feel wont be too different, then i might go for a slightly less expensive option.

Thoughts?

Cynikal 

The first question is what has your frame builder said about this and what tube set (or tube mix) are they recommending? Getting this off the internet is a little like walking in to the kitchen of a restaurant and questioning the ingredient choices of the chef. Some frame builders really take offence to this.

With that being said, the primary difference in the tube sets is in the wall thickness of the tubing. The difference in the steel makeup and tubing diameter allows for thinner tube walls. These factors effect the stiffness of the frame. There are a lot of gross generalizations here, this is pretty high level. Also consideration like disk brakes and what fork, carbon or steel, are important. I would add that I wouldn't limit a gravel or all-road bike to 32 mm, you can always run a smaller tire but 43 mm tires are awesome.

guy153

I'm surprised that the weight and price differences are as big as you're being quoted. 631 is only a little bit stronger than 4130. It's just meant to respond better to welding but not by so much that the tube gauges it's available in are any different. Here in the UK it costs about the same, but that's probably because it's one of the few things that are actually made here. It's a very nice product but not really any different in practice to seamless double-butted 4130.

853 is heat-treated 631 so is stronger and can therefore be made thinner. But most of the tubes available are not any thinner unless you get the ones branded "853 Pro-team", which you probably aren't as this is a gravel bike.

I would talk to your framebuilder about the actual gauges he's thinking of using. Most of the 853 tubes intended for gravel bike use are stronger but similar gauges. Given the use-case I would go with thin gauges for light weight and a lively comfortable ride-- something like 0.8mm/0.5/0.8 but probably "oversize" so 1 1/8" TT and 1 1/4" DT. Any of the three alloys suggested would be fine for such a frame, and if 4130 is significantly cheaper because of the side of the pond you're on, no reason not to use that.

guadzilla

Thanks for the info, guys.

The framebuilder makes really nice bikes- he's made a custom gravel-style bike for me back in 2012, before gravel even existed: lugged, clearance for 40mm tires with long reach caliper brakes. He's also made a steel lugged/carbon tubed bike for a friend that my friend really likes. But he's more of a MTB rider himself and isnt really able to provide the sort of nuanced answers on ride quality that I am looking for. So with him, the buyer needs to be a bit more informed about what s/he wants, in terms of tubing, gauge, etc.

So if i hear you guys correctly:
- there isnt a big difference between 631 vs 4130 - the specific tubings here would be a Taiwanese 4130 vs Reynolds 631 (with the Reynolds having some of their alloy additives)
- If I go with 853, it makes sense if i can get the 0.8/0.5/0.8 gauge with 1.125" TT and 1.25" to get the benefit of the better strength/size ratio of the 853

So it seems to be - either stick with 4130 or go for the 853.

Edit - just spoke to the builder. He is also recommended Omnicrom as an alternative, saying it might be a little more dent resistant. Any thoughts on Omnicrom vs 853 as a choice? Price is close enough to not be a factor.

guy153

0.8/0.5/0.8 would be absolutely fine in any of the three alloys. There isn't really any need for 853 unless you're using 0.6/0.4/0.6 on a lightweight road bike. But he won't be using that for a gravel bike. So the bike will weigh the same, ride the same, but just be stronger if you crash it.

Omnicrom sounds like awesome stuff but there's little to go on besides marketing material from Columbus or Reynolds Columbus have an anti dent treatment which I think is a kind of heat treatment. 853 is also heat treated and will therefore resist dents. But denting is unlikely to be a problem anyway.

wsteve464

Sounds like your builder is trying to sell you the top of the line tubing, 853 and Omnicrom are light weight tubing designed more for go fast road bikes. Below are some of the different tubing suppliers and the Columbus catalog links. All a gravel bike needs for tubing is a good mid level medium thick walled tubing the really thick tubes are for MTBs. All my opinion.



https://www.cycle-frames.com/steel/. (Nova)
https://www.bikefabsupply.com/steelbicycle-tubing
https://www.columbustubi.com/pdf/Colu...talogue-V3.pdf

Nessism

Dent resistance is a real thing. I remember back in the day when my ELOS frame, that had .4mm center butts, traumatically fell onto a bike rack striking the top tube in the middle and denting it. Oh the horror!

niknak

If she's less than 110lbs, then chances are she's shorter than 5'6". That means her road frames are pretty small. Also, it sounds like she's an experienced rider who is used to riding performance bikes. If you build her up a so-so bike, she will probably quickly wish she was on a nicer ride.

I guess I'm in the minority in that I'd definitely opt for thinner wall and smaller diameter tubes. A 1" .7/.4/.7 top tube and 9/8" .7/.5/.7 down tube would be great for her. Go with the lightest seat tube and seat stays the builder can get his hands on and the right chain stays for whatever max tire clearance she wants. The price difference among steel tubes isn't that great (excluding stainless).

Doug Fattic 

I completely agree with this. I'm a little guy and can tell the difference between light and medium wall thickness tubes and there is a good chance she could too.

guadzilla

To be fair to the builder, he isnt recommending anything - he is just giving me options that I asked for (and he's also a friend). And my rationale for trying to get nice steel is precisely for the reason mentioned below- want to get my wife a Good bike.

She's actually relatively new to cycling, but has been running for a while and seems to have better endurance genes than me - she won her AG in her first 70.3, wins bike races, etc. Since i have been riding for a while, I have a pretty good stable of bikes, but,she has a very nicely kitted out TT/tri bike, she's still on an entry-level Cervelo R2. We are struggling to find a geometry that fits her well for race bikes - so the plan was to get a nice training/adventure bike with a custom geometry for now, till we can get around to getting a proper bike fit done, at which point we'll pick up the race bike.

So yeah, i dont want to stick her with a heavy bike that she isnt excited about. She's also very light - under 110lb - so weight matters a fair bit for her. If the lighter/nicer bike is more fun to ride, I'd rather get that.

Also, re your recommendation - wouldnt a beefier downtube make more sense, for power transfer?

Re dents - what kind of risks are we talking about? On crashing or through normal usage with stones hitting the downtube, for example? If it is a greater chance of crash damage, i am not too worried - can always send it back and have the tubing replaced, if it comes to that. If it is damage from just riding around, that's a different story.

niknak

If she's less than 110lbs then I doubt she can produce enough watts to require a big down tube. I'm perfectly happy using the same down tube on my bike and I'm 165lbs and ride a much bigger frame than her. Remember, a frame for her will also be small. The smaller front triangle will be stiffer anyway. All you're doing is adding more weight and actually increasing the chances for the tube to dent by going bigger. Larger diameter tubes are more prone to denting than the same thickness tube in a smaller diameter.

IMO, the bigger tubes you see on steel bikes these days are just following the aesthetic trend of beefy tubing found first on aluminum, then ti, and now carbon. Steel doesn't need to be as big to perform the same.

I suggested using a 9/8" .7/.5/.7 downtube. That'll be just fine against road and gravel debris kicking up. I like to add a bit of clear protective tape to the underside of my frames that see off-road use, just to protect the paint.

guy153

Agree that 9/8 DT and 1" TT will ride really nice and be fine for power transfer and everything. I only suggested oversize because it's a gravel bike and it sort of goes with the chunkier stays you will end up with and general off-road robustness.

If you don't really need off-road capability maybe go for a road frame with 25mm max width tyres and pencil-thin seatstays with straight chainstays. I think this is the nicest riding setup for the road.

Doug Fattic 

I have ridden 7/4/7 frames with a 1" top tube I have made for myself for more than 30 years. I would not want to go with anything with heavier walls or larger diameter tubes. There is a liveliness I can feel that doesn't happen with heavier tubing. When I made my last one I was 5'8" and 135lbs. I think the myth that a frame should be unyielding to transfer power has been debunked. A frame rides the nicest when there is a bit of give that doesn't beat one to death that robs energy. As already mentioned, a smaller frame makes it stiffer and that needs to be compensated for too. I've been building for over 40 years and half of my customers have been females. It is also likely that she would be fit better on her bicycle if it had smaller wheels (unless she has a very aero position) but that is a subject for another thread.

In all those years I never had trouble with dents either. Heat treated tubing is more dent resistant. Well one time mine fell off of the roof of my car but of course that is special abuse. One of the reasons steel frames were made with more robust tubing is because most were made in a production environment not suited to treating light tubing with special care. Also they have to assume the rider might weigh a great deal more than your wife and needs stronger tubing so the frame won't break.

guy153

The one use-case where I think you do want a very stiff frame is if you are actually racing, specifically sprinting. But most of us never do that. 1" TT and thin-wall is very well suited to riding on the road. I wonder if the recent fashion for wide tyres is because frames have become bit too stiff.
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Andrew R Stewart 

This seems like the classic mistake of guys designing a women's bike and using their male driven competitiveness as the guide points. I've build a number (or at least for a hobby guy a bunch) of small lady's frames and can agree with the lack of the need for the stiffness that guy driven mags seem to market.

A 110 lbs and small in stature there's no way she needs a stiff and tight frame, unless she has raced at the highest levels and knows her stuff. And if that's the case the guys need to listen to her and not male speak for her. Andy

TenGrainBread 

A $500 upcharge for 631 vs. double-butted 4130 Taiwanese tubing is ridiculous.
First of all, a comparable double-butted 4130 tubeset made in Taiwan for Nova Cycle Supply, for example, costs around $115. That includes head tube, down tube, top tube, seat tube, chainstays, and seat stays.
A 631 tubeset goes for about $160 at retail.
Likewise, an 853 tubeset costs about $220.
So for an additional $1000 paid to the builder you can go from a $115 tubeset to a $220 tubeset. I understand that 853 is a little more difficult to work with given its thin gauge and hardness, but that's ridiculous.

631 doesn't even come in any particularly light gauges. A 200 gram weight reduction isn't enormous but it's hard to imagine where the builder is getting these numbers from, unless they uses some very porky touring gauge 4130. They need to be more transparent and specific about the cost of materials and labor and what is going into this quote.

unterhausen

I don't know why people are so quick to complain about a framebuilder expecting to be paid. This builder is probably under-charging for the cheap tubing as opposed to over-charging for the expensive tubing.

Andrew R Stewart 

Materials are the smallest part of the cost of making a frame. Time and tooling is generally the greater portion. Working with harder heat treated tubing is a lot more time consuming, unless you have the tooling (which has it's carrying costs). I've avoided using the harder tubes, more then I have done, for much of this reason. Thinner walls also take more care to handle and finish. I know of no builders who over charge for their products although I do believe many undercharge. Andy

himespau 

Since she already has road bikes, give serious consideration to allowing larger clearance for fatter tires. Maybe consider setting it up for 650b? I'm assuming this will be a disc brake frame?

guadzilla

Thanks for all the info, guys.

Point taken about the tube sizing - I dont have a lot of experience on what the tradeoffs re tube sizing vs stiffness are (and I also did not realize that my ignorance of these things is considered male-speak and a case of not listening to my wife, as one poster so virtuously put it :roll but it seems pretty unanimous that the 1" 7/4/7 and 9/8" 7/5/7 TT and DT would be the way to go. While this is definitely going to be a build with clearance for atleast 40-42mm tires - and yes, disc brakes - we dont expect to be doing anything particularly gnarly - just gravel and light off-road. Let's say 80% tarmac, 20% off road.

Re pricing - the builder is not in the US, and the custom duties here are all weird - and he also has to deal with MOQs (there isnt a lot of demand for 853, I imagine). As I said, guy is a friend and i am pretty confident that he is not ripping me off. The weight differences he gave me were just off-the-cuff, as well. Once we decide on the frame and geometry, he will get me more precise info.

So to narrow this down further - assuming we go with the tube sizing mentioned above, would the grade of steel make a big difference in ride quality? From what i can gather, it doesnt appear to be the case - but just thought I would confirm.

(Also - appreciate everyone taking the time to provide info - this has been super-helpful)

guy153

Correct, all steel will have the same ride quality if the wall thickness, diameter and geometry are the same.

Road Fan

OMG, I just had this happen 4 weeks ago with my Mondonico ELOS! But the good news is, it rides just as well, on the road and on the trainer.

fietsbob

4130 unlike 631 & 853 is not a individual company trade name. it's an AISI - SAE steel alloy designation..

guadzilla

Bumping this thread up with a follow-up question.

After much thought, we have decided to get Breakway-style bikes for both of us. I am gonna flip my Bike Friday and also my current steel bike (which has more of a CX geometry) and go for a more gravel-style design, with a greater BB drop and also disc wheels.

So 2 questions:

1/ Would that impact the tubing choices for her? 110lb, 1" 07/4/7 top tube, 9/8", 7/5/7 DT was what we had decided on, based on input here

2/ For an 180lb guy like me, who puts out more power and more torque, should i consider thicker diameter tubing? The builder feels that the above may be a little too noodly for me, but as I said, he's more of a MTB guy and not a roadie, so may be being overly conservative. He is suggesting something like the oversized tubes used by Battaglin.

guy153

What's your rough frame size? This also affects the noodliness. 1" TT and 9/8 DT with 8/5/8 or probably also 7/4/7 is fine at least up to about a 56cm frame I would say and I don't think your weight is a problem.