There Are No Cast Fork Crowns For Tapered Steerer Tubes

I don’t understand why there are no cast for crowns for tapered steerer tubes(1.125" to 1.5").

1 1/8" is in my opinion just fine for any steel fork (except when you need a light 1").

Maybe I’m missing something but from where I stand and the bikes that I ride and get excited about tapered headtube is just a not so pretty solution designed for carbon bikes.

Truly interested in hearing what reasons people have for using tapered headtube if not for using a carbon or moden suspension fork?

Edit: sorry this really doesn’t answer your questions, but maybe it puts a perspective into why? Hopefully someone can give a better answer :slight_smile:

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The real question: why are there fork crowns at all anymore? So obsolete. Modern bikes either have a sus fork or a plastic one. No one wants a steel fork! :wink:

Or if they do, they don’t want 1.5". Why would you ever want a 1.5" steerer in steel? Tandems, for downhill racing or BMX jumping? I mean even tandems don’t need 1.5" unless you’re doing something crazy on them. Pretty limited scenario I think! I have 2 tandems, both have a 1" steerer. I’m a Clydesdale, but 1" has been strong enough. One is a 1971, the other from 1988, haven’t been able to break either one.

What with the makers of cast lugs, BB shells and crowns going out of business for lack of sales, no one is looking to add another SKU to this dying market segment.

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aluminum bike polo specific frames use tapered head tubes/forks because of the extra load on the front from stoppies, nose pivots, coming down hard on the front doing wheelie turns, etc, but the steel polo specific frames use 1.125" because it’s adequate
i can’t imagine needing a tapered steel fork for any kinda of riding really

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I’ve designed (and also sell) investment cast fork crowns for 28.6mm steerers years ago and still offer them. Maybe comb my site for details.

Idependent framebuilders are making steel forks with steel tapered steerer tubes. Mass production framebuilders are also making steel forks with steel tapered steerer tubes. If framebuilders are going to continue building steel forks with steel steerers and steel crowns(as e-RICHIE suggests), then why not with crowns for tapered steerers? They could be done in a modern style. Not every cast crown has to look like a nostalgic artifact from previous decades.

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I see what you mean, I just think it’s bad engineering. Adding extra weight for no benefit. Even losing a benefit, namely the little bit of shock attenuation you can get from steerer flex just above the crown. If you’re a “stiffer is always better” fella then that last point will not be seen as a benefit to you, but surely you still care about weight?

Looking modern for no reason other than looks will never outrank proper optimized engineering, for me

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Because 1.5" tapered steel steerer tubes are dumb. Heavier than 1 1/8 and so ridiculously stiff. 1.5 in carbon was needed for better fibre path and bearing interface. Steel just diesnt need the extra and builders use it for fashion over function. THE best steel fork is the Columbus MAX blades in matching crown with a butted straight 1 1/8 steerer. In my opinion.

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If the forks are already being produced by both independent makers as well as manufacturers, what would having a crown add - except weight?

The art file you’ve added looks like a copy of a 1950s sand casting from Davis Components, or the top of one of those Ashtabula forks that came on Bike Boom era Schwinns.

To agree with DEVLINCC above, there’s a tipping point in using steel when these headset dimensions continue to grow. At some point, its very inclusion is the nostalgia.

Lastly, and to answer your original question (as Mark Bulgier also has), if you want the piece in the marketplace make it yourself and sell it to others. Be the provider not the consumer.

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A 420mm 1.125" Tange Champion steerer weighs 478g. A 420mm tapered steel steerer weighs 545g. That’s a difference of 67 grams.

A KitKat bar weighs 45 grams.

image

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Let me throw my opinion into the ring.

1) Forks fail below the crown, not the steerer tube

They are not the weak link. All the steel and Ti forks I have seen tested cracked where the legs are joined to the crown. The headset bearing supports steerer tubes very well, the steerer is not the weak link.

2) Tapered forks are for downtube size

Tapered forks were invented so you could use bigger downtubes (50-60mm) for carbon fiber bikes.

Framebuilders have this relationship backward. This is how it should be:

  1. Pick your downtube diameter
  2. Match your headtube diameter
  3. Design a fork to fit into this headtube

With steel bikes, very few people use more than a 38mm downtube. This is why I have been pushing for EC37. The headtube’s 40-42mm OD matches 95% of downtubes you would use on a modern steel bike.

So, from a technical perspective, tapered steel forks don’t make sense. People only use them for aesthetic reasons. This is because we got stuck with EC44/ZS44 HT in the first place.

Why don’t we have cast tapered fork crowns? Economics. It costs ~$3000-5000 to cut a casting mold. How many $40 fork crowns would you need to sell to break even? Probably 200-300.

Casting mold, somewhere in Taiwan:

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A 420mm 1.125" Tange Champion steerer weighs 478g. A 420mm tapered steel steerer weighs 545g. That’s a difference of 67 grams.

A KitKat bar weighs 45 grams.

I started designing (and selling to others) cast parts in the late nineties because I was disenchanted with the supply chain which, at the time, had been on life support. If you think this crown has merit, don’t rely on the industry to offer it. You are the industry now, as are many of us who survived the changing times.

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I am interested in the process(and economics) of investment casting bicycle parts. Any photos of molds or other technology related to the process would be greatly appreciated. One of the reasons I posted this thread was to determine if there is interest in an investment cast crown for the specified application.

I currently have about 3 dozen different cast parts on my menu. The originals were produced from handmade samples that were sent to the foundry with the instructions, “copy this.” After about six projects I started sending over Solidworks files but only after outputting a bunch of 3D samples to ensures everything edge, curve, and dimension was as desired. The foundries seem to only want art files now.

Each tool (every cast part requires a tool) cost a minimum of three thousand dollars. That’s your commitment to the project after the part is actually designed. Once the metal is being poured and parts shipped to you, the per piece price can be as low as ten dollars for a dropout set to over twenty for a bottom bracket shell.

It’s a commitment but NOT for the faint of heart. For me, after twenty five years of doing it, the tooling and start-up costs have long been amortized. And along the way, I’ve done my bit to keep framebuilders supplied. In another era, that job fell on industrial suppliers; they fed us. That ship sailed a long time ago. Now it’s your (the proverbial your) turn.

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I was at MADE in 2023, where I showed a bike with my 3D printed crown that uses a straight 1 1/8" steerer to create a tapered fork. The crown has a taper and a 40mm crown race seat built into it. At the show I chatted with @Carl_Snarl who said (if I remember right) he was working on a cast crown that would accomplish this. Maybe he can fill us in.

This is so true. What I did was have a crown made to the spec I was interested in. With 3D printing, MOQ is one unit and the price is not outrageous, so this is a process we all have access to. I have had a total of four crowns made for me this way.

Case closed then? Paragon and Engin don’t tend to make dumb stuff and they both offer tapered steel steerers. For the naysayers, here’s the reason I’m interested in them: you can use a steel fork, a carbon fork, or a suspension fork on the same bike with the same headset. Some folks would rather have flexibility and utility in a single bike than a shed full of bikes for specific purposes. It also allows for someone to change their mind later about what fork to run.

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Paragon and Engin offer tapered steerer tubes that are turned from tube stock. Bicycle Fabrication Supply and Incepi offer tapered steerer tubes made with a swaging process. People are using these products for exactly the reasons you have described.

A cast crown for a 1.5" steerer tube is just as rational as a cast crown for a 1.0" steerer tube or a 1.125" steerer tube.

A cast crown for a 1.5" steerer tube is just as rational as a cast crown for a 1.0" steerer tube or a 1.125" steerer tube.

Be the provider AND the consumer.

Exactly

OK now there’s a reason I can understand, thanks. Not for me, since I would never use a 1.5" steerer in any material. I’d rather walk than use a plastic fork and I don’t make bikes with sus forks. But I’m obviously an outlier there. I’m an old roadie stuck in the past and quite happy with that. You can safely ignore anything I say since the market and what I like diverged about 30 years ago.

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Your 3D printed crown has a taper incorporated into the crown. This allows it to be used with a non tapered steerer tube. It would be simpler to make the crown for a tapered steerer tube.