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cmbicycles
06-23-2012, 09:41 PM
I know this will open a can of worms, but I am considering getting a ti frame (which I have always wanted in lieu of my giant tcr composite) but have been seeing a few frames in stainless out there. Any opinions from those that have ridden the two materials for someone 6'5" 200lbs?
Thanks

jr59
06-23-2012, 09:48 PM
Paging Mr Dave Wages!

SPOKE
06-23-2012, 11:22 PM
Well, I have experience with both materials. I'm a fan of the new OS stainless pipes. The ride quality is nice and lively. Not springy like some Ti frames can be.
Be aware that the new SS material will show signs of corrosion if left with a brushed finish. If you get one that is polished to a mirror finish the surface corrosion isn't as much an issue. Lowest maintainence finish is to have it painted. The frame can be Tig welded or brazed with lugs.

Peter P.
06-24-2012, 06:15 AM
Costs for frames of either material will be virtually identical which means you don't have to debate price.

Either frame can be built to suit your weight and riding style by varying tube diameters so since you're thinking custom you can ignore any problems there.

I think the only thing to concern yourself with is, stainless doesn't really mean rust proof. You will see oxidation and staining if you don't perform a certain level of care for it. Titanium on the other hand, doesn't care how much you sweat on it.

I think the best application of stainless tubes is to still cover it with a paint job.

Titanium is tougher than stainless so it's less prone to denting and bending, such as in a crash.

cfox
06-24-2012, 06:39 AM
Titanium is tougher than stainless so it's less prone to denting and bending, such as in a crash.

I was hemming and hawing (sp?) the same thing, and this is one reason I ultimately went with Ti. Stainless is strong, but tube makers use that strength as an opportunity to draw the tubes paper thin, XCR is butted to .4 of a mm, and 953 can be even thinner. I knew that would be in my head every time I leaned my bike against a wall.

NHAero
06-24-2012, 07:56 AM
I am having a frame built from stainless tubes by Dave Anderson, it is in process now (he has been terrific to work with, BTW). I thought about the same material question, having had a Serotta Ti Concours, which was a great bike. In the end, it really was partially an aesthetic decision - I wanted lugs - and partially because I didn't want a carbon fork. As it turns out, the frame and fork are being made for disc brakes, so the custom fork is especially pertinent.

oldpotatoe
06-24-2012, 08:19 AM
I know this will open a can of worms, but I am considering getting a ti frame (which I have always wanted in lieu of my giant tcr composite) but have been seeing a few frames in stainless out there. Any opinions from those that have ridden the two materials for someone 6'5" 200lbs?
Thanks

Have owned a Waterford 953 stainless, and have a Moots. Different ways to do the same thing, IMHO. Loved the looks of the Waterford(sculpted polished lugs ans fork crown), but they both rode well. I personally think for the $, ti is the way to go.

holliscx
06-24-2012, 09:18 AM
IF's former president Matt Bracken said Ti is the best investment as far as frame material. Mike Flanigan of ANT said cost is the only reason not to go Ti; he works exclusively with steel. I think the stainless frames are hot but I just rolled the dice on a Ti Planet X.

Chance
06-24-2012, 11:01 AM
I was hemming and hawing (sp?) the same thing, and this is one reason I ultimately went with Ti. Stainless is strong, but tube makers use that strength as an opportunity to draw the tubes paper thin, XCR is butted to .4 of a mm, and 953 can be even thinner. I knew that would be in my head every time I leaned my bike against a wall.

Agree on dents, although the very thin stainless-steel tube walls are not driven just by its superior strength in my opinion. Like other steels, stainless is much heavier and stiffer than titanium. About twice as much on an equal size basis. If tube manufacturers didn’t make stainless tubes a lot thinner the frame would be too heavy and or too stiff. And weight does matter to most riders.

And unfortunately a very thin tube, even when made from stronger material, can often dent easier than a thicker tube of weaker material.

Chance
06-24-2012, 11:09 AM
Be aware that the new SS material will show signs of corrosion if left with a brushed finish. If you get one that is polished to a mirror finish the surface corrosion isn't as much an issue. Lowest maintainence finish is to have it painted.

I think the only thing to concern yourself with is, stainless doesn't really mean rust proof. You will see oxidation and staining if you don't perform a certain level of care for it. Titanium on the other hand, doesn't care how much you sweat on it.

I think the best application of stainless tubes is to still cover it with a paint job.

Why do they call it stainless if it stains or corrodes?:confused:

Had an old steel bike with some stainless tubes and never had corrosion problems at all. Don’t know about the new stainless steels but seems weird it would require maintenance or painting to keep it from rusting. It’s hard to think of that as “stainless”.

AgilisMerlin
06-24-2012, 11:10 AM
would love to try stainless

CaptStash
06-24-2012, 04:52 PM
Wait just one cotton picking minute here. 6' 5" and 200 lbs? Don't you ever eat? I;m worried about you man. Have milk shake already!

Stash... (the food police. Hey whaddya' want, my mom is a Jewish mother, and then I married a gal and waddya' know she turned into one too.. It rubs off after a while.)

SPOKE
06-24-2012, 05:11 PM
Why do they call it stainless if it stains or corrodes?:confused:

Had an old steel bike with some stainless tubes and never had corrosion problems at all. Don’t know about the new stainless steels but seems weird it would require maintenance or painting to keep it from rusting. It’s hard to think of that as “stainless”.

Different alloying elements that allow the material to be drawn into a tube with very thin walls. It also is pretty hard compared to other types of stainless. This bit of info still doesn't answer the corrosion question I know but I'm not a metallurgist.

Ken Robb
06-24-2012, 05:19 PM
If we still have to paint stainless what is the advantage over other quality steel tubes?

false_Aest
06-24-2012, 06:09 PM
Why do they call it stainless if it stains or corrodes?



stainLESS

not stainfree.


wuz how it was explained to me.

Louis
06-24-2012, 06:24 PM
I agree with what was posted above regarding thinner vs thicker tubes.

Assuming your builder will give you the ride qualities you want, whether you choose Ti or SS, I think Ti is a better material for a bike frame if only because over time the tubes will hold up better.

Ahneida Ride
06-24-2012, 09:49 PM
My Bedford will have a KVA SS rear and a True Temper front.

pdmtong
06-25-2012, 12:28 AM
My IF SSR SEC 953 is painted.

Looks great, rides great. Dents? none.

mvrider
06-25-2012, 01:29 AM
When I design stainless steel parts and have them machined, I always call for passivation at the plating shop, otherwise the impurities at the surface will nucleate corrosion. Perhaps the same is observed with stainless tubing?

http://en.wikipedia.org/wiki/Passivation#Stainless_steel

Stainless steel

Stainless steels are corrosion-resistant by nature, which might suggest that passivating them would be unnecessary. However, stainless steels are not completely impervious to rusting. One common mode of corrosion in corrosion-resistant steels is when small spots on the surface begin to rust because grain boundaries or embedded bits of foreign matter (such as grinding swarf) allow water molecules to oxidize some of the iron in those spots despite the alloying chromium. This is called rouging. Some grades of stainless steel are especially resistant to rouging; parts made from them may therefore forgo any passivation step, depending on engineering decisions.

A typical passivation process of cleaning stainless steel tanks involves cleaning with sodium hydroxide and citric acid followed by nitric acid (up to 20% at 120 °F) and a complete water rinse. This process will restore the film, remove metal particles, dirt, and welding-generated compounds (e.g. oxides).[3]

One aircraft manufacturer's corporate standard for passivation of stainless steel parts involves coating or submerging them in nitric acid solution for 40 to 60 minutes, then wiping them with water-soaked cloth.

Nonetheless, I am lucky enough to own not one, but two stainless bicycles, and neither is showing any signs of corrosion yet in dry California. Granted, there is paint and probably clearcoat over most of the surface. Gotta say, my Pegoretti Responsorium rides and handles way better for me than my (since sold) 2005 Moots Vamoots ever did.

Joachim
06-25-2012, 08:52 AM
I have owned both, Ti and XCr stainless. I also had a Spirit steel frame. There is no difference in ride quality between similar tubes from XCr or Spirit. Dave Wages has answered that question in a previous thread. Stainless has bling factor and the corrosion resistance is a nice added benefit. Given that steel and stainless steel have similar ride characteristics, your question is really the difference between steel and Ti. That is very much builder dependent. For example, my Spectrum Super Ti rides like a super light MX Leader.

Dave Wages
06-25-2012, 04:27 PM
I know this will open a can of worms, but I am considering getting a ti frame (which I have always wanted in lieu of my giant tcr composite) but have been seeing a few frames in stainless out there. Any opinions from those that have ridden the two materials for someone 6'5" 200lbs?
Thanks

We had an engineer at Serotta back in the day who had a great quote, "there are no bad materials, only bad applications". Essentially what I'd say is, you could build a fine bike out of ti, stainless or regular steel as long as it's designed properly. I'm pretty close to your size, 6'5" and about 195lbs, and I'm riding the KVA tubed rando bike that I built for NAHBS this year with no problems. If I were building more of a straight ahead road bike, I'd probably go with XL diameter tubes for someone my size, but I wanted to try out the standard OS tubes for that particular bike.

Regarding the questions about corrosion resistance, I've got a few chunks of polished 953 and KVA tubing that have been sitting outside through the Wisconsin weather since last year, and they're yet to show any noticeable surface corrosion. Like others have mentioned, the high polish is much less prone to corrosion IMO. The downside is that the high polish adds $$$'s to the bottom line since it's so labor intensive.

Cheers,
Dave

CaliFly
06-25-2012, 05:04 PM
We had an engineer at Serotta back in the day who had a great quote, "there are no bad materials, only bad applications". Essentially what I'd say is, you could build a fine bike out of ti, stainless or regular steel as long as it's designed properly. I'm pretty close to your size, 6'5" and about 195lbs, and I'm riding the KVA tubed rando bike that I built for NAHBS this year with no problems. If I were building more of a straight ahead road bike, I'd probably go with XL diameter tubes for someone my size, but I wanted to try out the standard OS tubes for that particular bike.

Regarding the questions about corrosion resistance, I've got a few chunks of polished 953 and KVA tubing that have been sitting outside through the Wisconsin weather since last year, and they're yet to show any noticeable surface corrosion. Like others have mentioned, the high polish is much less prone to corrosion IMO. The downside is that the high polish adds $$$'s to the bottom line since it's so labor intensive.

Cheers,
Dave

^^^ Part of the reason this board is the bees knees. :banana:

zap
06-25-2012, 05:17 PM
snip


Regarding the questions about corrosion resistance, I've got a few chunks of polished 953 and KVA tubing that have been sitting outside through the Wisconsin weather since last year, and they're yet to show any noticeable surface corrosion. Like others have mentioned, the high polish is much less prone to corrosion IMO. The downside is that the high polish adds $$$'s to the bottom line since it's so labor intensive.

Cheers,
Dave

You throw some road salt and water on those tubes?

jr59
06-25-2012, 05:19 PM
We had an engineer at Serotta back in the day who had a great quote, "there are no bad materials, only bad applications". Essentially what I'd say is, you could build a fine bike out of ti, stainless or regular steel as long as it's designed properly. I'm pretty close to your size, 6'5" and about 195lbs, and I'm riding the KVA tubed rando bike that I built for NAHBS this year with no problems. If I were building more of a straight ahead road bike, I'd probably go with XL diameter tubes for someone my size, but I wanted to try out the standard OS tubes for that particular bike.

Regarding the questions about corrosion resistance, I've got a few chunks of polished 953 and KVA tubing that have been sitting outside through the Wisconsin weather since last year, and they're yet to show any noticeable surface corrosion. Like others have mentioned, the high polish is much less prone to corrosion IMO. The downside is that the high polish adds $$$'s to the bottom line since it's so labor intensive.

Cheers,
Dave


Thanks Dave, you are the best!

Ahneida Ride
06-25-2012, 05:23 PM
The downside is that the high polish adds $$$'s to the bottom line since it's so labor intensive.

Cheers,
Dave

Hey Dave ...

ask Kelly about polishing a SS rear end to a mirror finish ...
Ha ! that's what he did on mine ......
It's an amazing amount of hand labor.

soulspinner
06-25-2012, 05:47 PM
^^^ part of the reason this board is the bees knees. :banana:

+1

Dave Wages
06-25-2012, 11:30 PM
snip



You throw some road salt and water on those tubes?

Well, I've got my own bike as a test subject, and the tube bits have just been sitting outside my window all winter in whatever conditions Mother Nature throws at them. I suppose if you ride your bike in the Dead Sea, then you should probably wipe it down a bit afterwards, that's not going to be good for anything! ;)

pdmtong
06-25-2012, 11:43 PM
We had an engineer at Serotta back in the day who had a great quote, "there are no bad materials, only bad applications".

the other version is "there is no such thing as bad weather, only bad clothes."

dave...any pref between 953, XcR or KVA...? is the choice mainly about supplier availability nowadays?

fogrider
06-26-2012, 04:42 AM
the thing that makes stainless steel resist rust is nickel. the more nickel, the more resistant to rust. common nickel is pretty soft, but for bicycle tubing, it has to be harder and thin to keep the weight down.

zank
06-26-2012, 08:36 AM
A quick metallurgy lesson.

There are three general families of stainless steel: martenstic, austenitic, and ferritic. The names describe the dominant crystal structure of the steel at room temperature. We won't discuss ferritic as it really doesn't bring anything to the discussion.

The stainless steel used in current bicycle tubing sets is drawn from a martensitic grade of stainless steel (400 series). All three companies are elusive about exactly which grade. Martensitic steels are heat hardenable to high tensile strength, which is what allows the manufacturers to draw thin wall tubing of adequate strength. These grades have lower chromium content compared to the more familiar austenitic grades and have very little or no nickel.

The austenitic grades (300 series) are what most people think of when they hear the generic term "stainless steel" because they are used in cutlery, most appliance applications, and many other common applications. These grades contain greater amounts of chromium than martensitic, and nickel is added to make the austentite crystal stable at room temperature. Nickel is not added to increase corrosion resistance. The austenitic grades are not heat hardenable, are very tough, but do not have the tensile strength of a heat hardened martensitic grade. Most of the 300 series grades have lower tensile strengths than 4130. If we tried to make a bike out of say 304 stainless tubing, it would be heavier than a frame made of 4130 and be very expensive.

Chromium provides the corrosion resistance in stainless steel by combining with oxygen to form a passive surface layer of chromium oxide. The martensitic grades have lower chromium content (11.5%-18% depending on the grade) compared to the austenitic grades (16%-26% depending on the grade). The reduction in quantity of chromium in the martensitic grades is what contributes to the staining that's seen in some bicycle tubing. But that's really only part of the story. Any free iron on the surface of the metal will form iron oxide (rust) and give the appearance that the tube is rusting. How does the iron get there? Usually from using steel cutting tools during fabrication or while maintaining the bike, a chain slapping a chainstay, or a steel fastener or ferrule coming in contact with the frame. There is also the chance that the chromium oxide layer is scratched off and iron oxide forms before the chromium oxide can form to "seal" the surface. This happens rarely in the austenitic grades because of the quantity of chromium present in those grades. As mentioned, passivation removes the free iron on the surface of the steel with an acid, but it doesn't prevent further iron from being deposited on the surface.

There is a lot of bad press out there about bikes being made of stainless steel tubing. That is because it is often built the same way a steel frame is built. The two materials should be considered entirely different. In terms of preparation and back-purging, it must be treated in the same way as titanium. In addition, stainless steel transfers heat much more slowly than any other metal used in bicycle tubing. It also has a much higher coefficient of thermal expansion. So there is a greater chance of localized overheating during welding and brazing and it will distort to a greater extent. If the builder is not prepared for this, the end product can simply be a mess. By the book, these grades should also be heat treated after welding to bring them up to full hardness.

I have also done some backyard corrosion tests and had similar results to what Dave found. I welded up some sample joints in both KVA tubing and XCr tubing. I passivated some samples, put a brushed finish on some samples, and left some samples as-welded. I threw them in a bucket with some salt water and left them there for a few months. I sloshed them around from time to time. The brushed and passivated samples showed no staining. The as-welded samples showed some staining and pitting in the heat affected zone after a few months.

Hope this all helps. It probably won't help the OP decide what kind of bike to get, but it might clear up some of the mysteries around stainless steel. The common joke is it shouldn't be called stainless steel because it's neither stainless nor steel.

Fixed
06-26-2012, 08:48 AM
zank is king
nice post thank you
cheers :)

EnginCycle
06-26-2012, 10:44 AM
Just to add to the test the guys have been doing with the outdoor elements. The key to seeing if this is going to last is having oxygen in the mix. As Mike said he shook the bucket occasionally but it would be even better if you just sprayed the piece with salt water and let the air dry it and see how it handles it. There is no denying that the rougher the finish the more prone to staining. The reason the heat effect zone is prone to rusting is because when you heat these materials it draws the iron (yes iron) content that is in the material to the surface. If this iron is not sanded, then buffed out and off the material it will rust. The rust is more of a stain on the surface and it not as much of a structural issue as standard high carbon steels. In many cases a light patina of rust is a protective shell but if you have the type that is pitting and penetrating the material then it is bad.

This is purely my opinion but I have given up on stainless as a material used in making bicycles. I felt the stuff available was too difficult to get my hands on and when I did there were quality control issues that I needed to deal with. True Temper S3 is about the same material if you plan on painting the bicycle.

I have since decided to devote my time to titanium and feel it is a better (for my applications) product for its dent resistance and it is actually rust proof (actually the rust on ti is the protective shell that you get from it being mixed with the air and is what helps it maintain a constant color). There are still some availability issues to deal with and there is definitely a difference in Ti. Just being grade 9, 3/2.5 or 6/4, CWSR (cold worked stress relieved) is not all that matters. The more domestic product you can get your hands on the better your product will be.

Again this is not a pointing fingers type response. I need to be able to bend the rear stays, make stuff able to handle disk brakes, long dt's that support front suspension, etc, etc. These hurdles were all less complicated to get over with Ti compared to stainless. It was essentially impossible to make a COMPLETELY stainless steel 29R and this was something I tried to do for many years. It just never came to be and I accept that.

Thanks for reading.

Cheers,
Drew

Lionel
06-26-2012, 11:58 AM
My XCR bike is painted. Belt and suspenders :)

Pete Mckeon
06-26-2012, 01:51 PM
BUT #1 priority should be designed for your purpose and also a good fit!

Spokes and I are good friends and neighbors. We do always disagree on somethings but many others we never disagree.

I have had ti for over 12 years and never a SS but then I am Serotta biased.:roll eyes:


Pete (aka Serotta Pete in past forums)

Chance
06-26-2012, 04:25 PM
Love titanium for bikes, and also for its unique property which promotes bone to grow in such close proximity to the titanium that it effectively adheres to the metal. Just in case our cycling doesn’t go as planned.:rolleyes:

Ti Designs
06-26-2012, 04:31 PM
I want to know who this stainless guy is...

soulspinner
06-27-2012, 05:58 AM
Just to add to the test the guys have been doing with the outdoor elements. The key to seeing if this is going to last is having oxygen in the mix. As Mike said he shook the bucket occasionally but it would be even better if you just sprayed the piece with salt water and let the air dry it and see how it handles it. There is no denying that the rougher the finish the more prone to staining. The reason the heat effect zone is prone to rusting is because when you heat these materials it draws the iron (yes iron) content that is in the material to the surface. If this iron is not sanded, then buffed out and off the material it will rust. The rust is more of a stain on the surface and it not as much of a structural issue as standard high carbon steels. In many cases a light patina of rust is a protective shell but if you have the type that is pitting and penetrating the material then it is bad.

This is purely my opinion but I have given up on stainless as a material used in making bicycles. I felt the stuff available was too difficult to get my hands on and when I did there were quality control issues that I needed to deal with. True Temper S3 is about the same material if you plan on painting the bicycle.

I have since decided to devote my time to titanium and feel it is a better (for my applications) product for its dent resistance and it is actually rust proof (actually the rust on ti is the protective shell that you get from it being mixed with the air and is what helps it maintain a constant color). There are still some availability issues to deal with and there is definitely a difference in Ti. Just being grade 9, 3/2.5 or 6/4, CWSR (cold worked stress relieved) is not all that matters. The more domestic product you can get your hands on the better your product will be.

Again this is not a pointing fingers type response. I need to be able to bend the rear stays, make stuff able to handle disk brakes, long dt's that support front suspension, etc, etc. These hurdles were all less complicated to get over with Ti compared to stainless. It was essentially impossible to make a COMPLETELY stainless steel 29R and this was something I tried to do for many years. It just never came to be and I accept that.

Thanks for reading.

Cheers,
Drew

Thanks for the response, interesting thread.

christian
06-27-2012, 07:42 AM
If I were in the market for a road bike, I'd be interested in Ti or a steel bike with stainless chainstays.

For a mountain bike, Ti all the way. (But, for me, personally, I'd probably get a steel Coconino...)