"forged" cranks, what a crock?

[Jason Knight]

I've seen more and more bikes listing "forged" cranks as if 1) they're actually forged, and 2) as if it's something to be proud of.

Is it just me, or do these in fact have jack to do with "forging" and instead are just ultra-heavy sand-cast pig iron? I'm asking because two friends had these on their cruiser bikes, and my aventure came with same... and they're overweight soft junk. Replacing the ones on my Aventon with some simple cheap aluminum "$30 e-bay specials" -- as part of my swapping up to a 52 tooth chainring -- knocked over two flipping pounds off the bike! Much less they just feel more durable. It's a laugh when I go from 3.12 pounds of cranks and chainring to 1.1 pounds, whilst making it feel higher quality.

How cheap can cheap get? It's shocking how the marketing turds seem to try and sell a negative as a positive... much less use terms like "forged" that they clearly have zero blasted clue what it means; because if what I've seen of these is "forged", I'm the Queen of England... well, unless they mean forged as in fake, not as in "shaped using heat and hammering".

Casting is not forging.

Guess it could be worse, I've been seeing more and more cheap bikes coming with stamped cranks... 'cause yeah, stamped metal handles stresses SO well.

 

[Stefan Mikes]

Perhaps if you bought a decent e-bike, alloy Praxis cranks could actually be "cold forged" there.

 

[tomjasz]

Chinglish often confounds descriptions.

 

[Bubba zanetti]

Perhaps if you bought a decent e-bike, alloy Praxis cranks could actually be "cold forged" there.

 

[RunForTheHills]

Alloy cranks are definitely superior to steel. Whether it is forged or cast, who wants to carry all that extra weight around? It is just another way manufacturers cut costs.

 

[Pulsar]

Don’t see forged cranks as even being needed. You have die forgings and hand forgings. Forgings just get the metal grain going in desire directions for structural reasons. Then you still need to machine the forging to shape. High speed machines are cheap enough now to machine from an aerospace alloy complete, shot peen it and powder coat. Stress analysis via computer allows you to optimize machining for thick and thin areas so you get strength exactly where needed. One would have to be hell bent to damage a 7075, 7050, or 2024 alloy crank. Weight would also be very light with these alloys.

 

[john peck]

I've seen more and more bikes listing "forged" cranks as if 1) they're actually forged, and 2) as if it's something to be proud of.

Is it just me, or do these in fact have jack to do with "forging" and instead are just ultra-heavy sand-cast pig iron? I'm asking because two friends had these on their cruiser bikes, and my aventure came with same... and they're overweight soft junk. Replacing the ones on my Aventon with some simple cheap aluminum "$30 e-bay specials" -- as part of my swapping up to a 52 tooth chainring -- knocked over two flipping pounds off the bike! Much less they just feel more durable. It's a laugh when I go from 3.12 pounds of cranks and chainring to 1.1 pounds, whilst making it feel higher quality.

How cheap can cheap get? It's shocking how the marketing turds seem to try and sell a negative as a positive... much less use terms like "forged" that they clearly have zero blasted clue what it means; because if what I've seen of these is "forged", I'm the Queen of England... well, unless they mean forged as in fake, not as in "shaped using heat and hammering".

Casting is not forging.

Guess it could be worse, I've been seeing more and more cheap bikes coming with stamped cranks... 'cause yeah, stamped metal handles stresses SO well.

Just a marketing ploy, next they´ll be ´hyper-forged´.

 

[rich c]

Most of the trouble with cranks is that people don't use torque wrench. Of course there are also the other group that don't know what a left hand thread is. True forged cranks, from a proper alloy, certainly do make a difference. And I agree with Stephan, you won't get top quality cranks on a $2,000 eBike.

 

[Jason Knight]

Most of the trouble with cranks is that people don't use torque wrench. Of course there are also the other group that don't know what a left hand thread is. True forged cranks, from a proper alloy, certainly do make a difference. And I agree with Stephan, you won't get top quality cranks on a $2,000 eBike.

And that still sets off my BS alarm; that putting $750 to $1000 in motor, controller, and battery on a bike with parts inferior to a $200 Walmart special is magically worth three and a half to four grand? BULLCOOKIES. 200% or more markup they should be hand delivering it to my door, assembling it for me, and giving me a happy ending at that point! 'Cause I've seen Pedego's and the offerings from other brands at the one remaining ski shop pretending they sell bicycles here in that $3500 to $4000 price range, and the BEST of them stripped of the electronics are just $150 Micargi's I could get for $100 a pop direct off the slow-boat in batches of five. Excuse me if I think marking it up three grand just because a motor is added is a bit absurd! Turns it into a "rich man's sport" -- hardly ideal when the biggest target audience seems to be seniors and the upper end of the middle aged.

Not that there's anything wrong with cheap Micargi's, I rode one of their cruisers for over a decade.

I've gotten better support and value out of the $20 crock pot I wax my chains in.

"Alloy" is another of those words I'm seeing that seems more marketing BS than reality; since if often seems they don't say WHAT metals are in said alloys. The cranks with that label seeming inferior in both weight, feel, and durability to -- again -- simple milled aluminum. I guess it's like web development frameworks -- the bane of my existence as an efficiency and accessibility consultant -- where words like "easier", "simpler", or "better" are bandied about when it's all just marketing nonsense to prey on those who don't know any better... the exact opposite being what's pedaled to fanboys who react the same as religious extremists / cultists when you dare to ask "HOW is it any of those things?".

Almost makes me want to get into the business of making these things... if you can get away with 200 to 300% markup on off the shelf parts and people will actually spend that.... And to think the norm twenty-five years ago for turnkey assembly (of anything) was 33%.

 

[mschwett]

if one is deeply offended by the choices a manufacturer makes to hit a certain price point, and a certain profit margin (it's highly unlikely these companies are operating far outside the norm for the latter, if they were, someone would swoop in and undercut them badly), the good news is you can not buy their product, build your own, buy someone else's, or whatever!

the bike industry is odd. you can pay $150 for an entire bicycle at walmart or wherever, or you can pay $150 for a tiny piece of milled aluminum, or $450 for just a seat, or $4,000 for the latest dura ace groupset... and dollars to doughnuts the companies which make each of those things are making very broadly the same range of profit in terms of order of magnitude. if any of them were making 300% profit margins, the market would invent a competitor for them very quickly.

 

[Jason Knight]

the companies which make each of those things are making very broadly the same range of profit in terms of order of magnitude. if any of them were making 300% profit margins, the market would invent a competitor for them very quickly.

Sadly that is often the ideal and the bs story we've been spoon fed, In my experience that's not how it works; it's now how any of it works. I see this in computer tech all the blasted time, where companies like crApple marks up the crap out of their rinky, half-assed, cost cut designs and then use marketing scams to position their products as status symbols.

Or in telecoms, where service providers all have mutual agreements not to compete in each-other's regions. Cable and Internet providers are the same way, they are for all intents monopolies who can charge whatever the hell they want, because they're the "only game in town". Not the same problem, but the same fallacy of so-called "free markets".

Let's use Pedego as an example, a company who's products I looked at and completely balked at their batshit prices. Their frames are LITERALLY your sub $200 beach cruisers from the likes of Firmstrong, Micargi, Titan, etc. The drivetrains are basically the same stuff companies like Nakto put on them; Shimano Tourney shifters and derailleurs, Shimano "hyperglide" 7 speed cassettes... they also use non-name rebranded motors and controllers, with the only thing warranting a price bump being their use of a better brake kit from Tektro.

You look at their "interceptor" for example, and it's a sub $200 beach cruiser, with a $250 disc brake kit, a $500 no-name motor conversion kit, a $200 battery mounted to a $30 rear rack. And they're asking three grand. And that's me quoting retail prices.

Again, makes one want to get into this business because if there are marks, suckers, and fools out there easily bamboozled into spending that type of money...

You climb up the ladder to something a bit less off the shelf and, well... Compare their "Trail Tracker" to the Aventon Aventure, they're almost identical apart from the Pedego having shorter cranks, less useful gearing, weaker motor, smaller battery, superior brakes (though that's debatable since we're talking 180mm vs 150mm), inferior headlight, inferior shifter, and of course no suspension fork. The Aventon even comes with a more powerful name brand motor and controller, instead of some rebranded who-knows-what.

And again, the bullshit "forged aluminum" cranks that I've seen in person, and look -- and feel -- and weigh -- what should be cast pig iron.

So where's that extra $2600 in price coming from? I don't care how huffing good their support is, it's not worth $4500 for their offerings -- like every other brand I've looked at in that price range -- is utter bullcookies. It's Warhol's "Illusion of value". They have BS overpricing because they prey on people who don't know any better. Thus their over the top marketing campaign, opening of franchise stores, and trying to ingratiate themselves like most snake oil peddlers do.

 

[K PierreR]

How do you all know that these cheap cranks are not forged. Cranks are a safety critical item set with minimum standards. Even one failure would be devastating to a companies reputation and sales. Modern forging is relatively cheap. The alloy makes more difference as well as cold or hot forging. Forging eliminates defects. I do not believe that there are any manufacturers that are casting cranks. Casting cranks would be more expensive than forgings.

 

[Jason Knight]

How do you all know that these cheap cranks are not forged.

Uniform coarse outer texture, flash lines, ground down spots from the pour and bleed holes. Just as weight indicates composition. If they are "forged" the most they got was a single heating and then a post-cast stamping. Remember, if you stamp it while hot, that still counts as "forged' even though it does nothing in terms of making it better; just makes it "prettier" in terms of details.

Cranks are a safety critical item set with minimum standards.

Are there actually standards?

Even one failure would be devastating to a companies reputation and sales.

Who says they're going to fail just because they're cast. Cast iron or many iron alloys are more than durable enough after casting to handle the rather weak sub-300 pound loads someone pedaling would create. Remember, it's effectively impossible for a crank to undergo more force than the weight of the rider... which is bupkis in terms of material stresses when talking about what for all intents and purposes is a half inch by one inch or larger slab.

The alloy makes more difference as well as cold or hot forging. Forging eliminates defects.

Defects that might not even matter... though good point about "the alloy" because the question becomes WHICH ALLOY?!? People talk about "alloy cranks" and you see the word thrown around as a sick marketing buzzword.... Brass and Bronze are alloys, Solder is typically a zinc-tin alloy. Doesn't mean you use them for cranks. Titanium-aluminum alloy would be the ideal, but when people are just saying "alloy" without specifying, it's pretty questionable. Folks seem to throw around the word "alloy" like some form of marketspeak double-talk; as if it means some type of unobtainium wonder-metal out of the pages of a comic book.

I do not believe that there are any manufacturers that are casting cranks. Casting cranks would be more expensive than forgings.

Casting more expensive than forging? DA****? What are you on and where can I get some? Casting is fast and simple, particularly sand casting at the industrial scale. When you can cast a dozen or more in a single pass, and then only use a bit of light grinding and polish to finish them? It's many times less labor and faster.

And cast isn't uncommon on cheap bikes. See Ashtabula cranks where you're as likely to see cast as you are forged. The cast ones are often better quality than forged since most "forging" of such cranks involves taking a steel rod, heating it enough to bend, doing one press, and saying "done" without even bothering to heat treat it before welding on the pins/mounts for the chainring. You really think they're pounding and shaping over and over to "drive out impurities" on those? BULLCOOKIES!

In fact, forged one piece cranks are a good chunk of why the throwing around of the word "forged" strikes me as marketing BS used to prey on people who don't know what forged means. It means heated and shaped. I heat up a rod of 330 and put a bend in it, it's "forged". Doesn't mean I've done dick in terms of aligning the structure or driving out impurities.

Either way, wasn't really kvetching about strength, so much as the weight and the easy by which one slip and you've got tool marks all over the place. Again, took 2.5 pounds off my bike by switching from "forged" cranks to some cheap milled aluminum ones.

 

[rich c]

Alloy is not a marketing term. All metals are made from an alloy recipe. At Caterpillar we experimented with some castings from China. We had a ton of tooling issues machining some engine blocks. On a follow up trip to the foundry in China, the engineer found that they were sweeping floor trash into the pot of cast iron. That included glass Coke bottles which put glass filled voids in the blocks. It's hard to machine glass.

 

[indianajo]

Alloy is not a marketing term. .

It is when nobody controls the word. It is not copyrighted, nobody will sue if the term is misused by some marketing type. When you get an ASTM report with a metal product, the reputation of the vendor stands behind it. A truck spring maker told me he was getting great test reports with the 4130? steel he was buying from a wholesaler, but the material made in ***** was inconsistent with hard spots & flexible spots. Maybe the whole billet met spec, but his piece of it did not. **** Crucible Steel is out of business.
I broke a bargain 3/8" chain last Friday trying to pull a crane out of the dirt it sank into. Breaking chains is very dangerous to operators (me). I just bought $400 of 7100 lb test 3/8" chain and 7500 lb hooks from mcmaster. Will be stamped with test proof, and likely will not be made in *****. Most stuff from mcmaster is from twn, tha, or kor. They are not cheap. Chromate plated too, not much more rust.
Crane has a 1/2" cable on the winch, only rated to 5300 lb mcmaster says. Winch was stalling before the chain broke. May need a new hydraulic pump; the Perkins motor is great. 1968 Drott crane.

 

[Jason Knight]

All metals are made from an alloy recipe.

Another "what the?!?" statement. Copper is not an alloy. Tin is not an alloy. Iron is (or shouldn't be) an alloy. Lithium is not an alloy. Titanium by itself is not an alloy (though generally not useful until you work it into one). Aluminum is not an alloy.

STEEL is an alloy (iron and carbon). Bronze is an alloy (copper and tin). Brass is an alloy. (copper and zinc).

 

[Stefan Mikes]

Aluminum is not an alloy.

Pure aluminium is not an alloy. However, aluminium alloys are construction materials, commonly used in bikes/e-bikes. Hence the Alu alloy names such as 6061.

 

[kmccune]

I've seen more and more bikes listing "forged" cranks as if 1) they're actually forged, and 2) as if it's something to be proud of.

Is it just me, or do these in fact have jack to do with "forging" and instead are just ultra-heavy sand-cast pig iron? I'm asking because two friends had these on their cruiser bikes, and my aventure came with same... and they're overweight soft junk. Replacing the ones on my Aventon with some simple cheap aluminum "$30 e-bay specials" -- as part of my swapping up to a 52 tooth chainring -- knocked over two flipping pounds off the bike! Much less they just feel more durable. It's a laugh when I go from 3.12 pounds of cranks and chainring to 1.1 pounds, whilst making it feel higher quality.

How cheap can cheap get? It's shocking how the marketing turds seem to try and sell a negative as a positive... much less use terms like "forged" that they clearly have zero blasted clue what it means; because if what I've seen of these is "forged", I'm the Queen of England... well, unless they mean forged as in fake, not as in "shaped using heat and hammering".

Casting is not forging.

Guess it could be worse, I've been seeing more and more cheap bikes coming with stamped cranks... 'cause yeah, stamped metal handles stresses SO well.

Casting is not all bad if done correctly, especially if "forging" is torturing something into place, a pressure casting machine makes a very good product( ask Mr.Musk about that)
OTH I have had some early import castings that were porous and pure junk!" Caterpillars "cast steel parts are second to none. Now though you have me on the replace crankset bandwagon.

 

[kmccune]

Pure aluminium is not an alloy. However, aluminium alloys are construction materials, commonly used in bikes/e-bikes. Hence the Alu alloy names such as 6061.

Right on there are Aluminum alloys that rival a lot of steel alloys in tensile strength,I believe "Duraluminum" has a tensile strength of 70,000 PSI, not bad for something that light