# Advantages of "true" fixie crank vs. coverted road crank?



## Johnny LaRoux

*Advantages of "true" fixie crank vs. converted road crank?*

What, if any, are the advantages of running a true fixie or track crank on a converted fixie, as opposed to a converted road crank?

I'm currently running a converted DA 7700 with 175mm arms on my converted Proctor, and want to get a set with shorter crank arms, say 170mm. I've found some 105's brand new on ebay for $40, and I wouldn't have to change my Octalink BB. Probably the cheapest route, but would I be better off spending a bit more and getting some track cranks?

Aside from the bling factor of say Sugino Messengers, am I really getting more bang for the buck?


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## roadfix

Aside from perhaps stiffer rings, track cranks usually are easier to set up as far as chain lines go, usually regardless of whether your converting an old road frame or using a true track/fg frame.

But OTOH, some track cranks may not work with certain road frames due to clearance issues (usually crank arm/chain stay clearance)

"true" fixie cranks are usually just converted road cranks sold and marketed as such by merchants......so they're not true track cranks.


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## ukiahb

true track cranks are truly round so chain tension does not vary and is much easier to set and the bike runs smoother too...this precision costs more to manufacture so that is why they are more expensive, but well worth it IMHO if you are going to ride the bike a lot and keep in for a long while. There is an article on this at http://www.peterwhitecycles.com/fixed.asp


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## Dave Hickey

ukiahb said:


> true track cranks are truly round so chain tension does not vary and is much easier to set and the bike runs smoother too...this precision costs more to manufacture so that is why they are more expensive, but well worth it IMHO if you are going to ride the bike a lot and keep in for a long while. There is an article on this at http://www.peterwhitecycles.com/fixed.asp


+1..true track cranks are round and don't have tight and loose spots during a revolution... I've yet to have a road crank/ring that is truly round

My 3Rensho is using a Dura Ace track crank and ring and a Phil Wood cog...It is super quiet and there are no tight/loose spots..


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## palu

Could you guys recommend a decent track crank at a decent price?


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## tihsepa

http://www.benscycle.net/index.php?main_page=product_info&cPath=188_193_655&products_id=357

Here you go. These guys are not the cheepest around but their customer service is second to none.


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## roadfix

A from Il said:


> http://www.benscycle.net/index.php?main_page=product_info&cPath=188_193_655&products_id=357
> 
> Here you go. These guys are not the cheepest around but their customer service is second to none.


Again, these are not true track cranks....they're merely converted road cranks.


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## Dave Hickey

roadfix said:


> Again, these are not true track cranks....they're merely converted road cranks.



+1...Agreed and track cranks are usually 144 BCD and are very expensive...

You are usually going to pay $200-$300++ for a quality track crankset...and that doesn't include a bottom bracket..

Check eBay for used Dura Ace 7600 cranks...They are equal to the Sugino 75 yet the aren't as popular with the fixie crowd..

This guy sell used Sugino 75 and Dura Ace 7600 crank arms and rings... I've bought from him many times...He takes paypal

http://njs-keirin.blogspot.com/2007/11/njs-cranks.html


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## DIRT BOY

palu said:


> Could you guys recommend a decent track crank at a decent price?


SOMA Hellyer.












let me know if I can help.


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## Dave Hickey

I love that drillium chainring


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## ukiahb

palu said:


> Could you guys recommend a decent track crank at a decent price?


I've been using a Sugino 75 for nearly 5 years and many miles, am very happy with it....FWIW got it from http://www.businesscycles.com/


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## Johnny LaRoux

roadfix said:


> Again, these are not true track cranks....they're merely converted road cranks.


What about Sugino's Messenger cranks? Are they "true" or "road"?


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## Richard

Johnny LaRoux said:


> What about Sugino's Messenger cranks? Are they "true" or "road"?


The Sugino Messenger is just a repackaged RD (i.e. road) 48. Originally designed as a 130mm bcd double but, with a 103 to 107mm spindle, it produces a pretty good chainline with the ring on the outside (I have one on the Raleigh commuter.) Good crank but that is "marketing."

Dave's right. Dedicated track cranks are 144mm bcd and come with VERY ROUND (and therefore very expensive) chainrings. As to stiffness, I doubt a Sugino, Shimano, Campy, or Miche track crank is noticeably stiffer than the mid-'80's FC-6207 Shimano 600 with a 130mm bcd that I have on my fixed. And with some creative tweaking, I was able to run the ring in the outside position and still get a good (and dead quiet) chainline.


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## Richard

Searching around found a decent picture of my crank since I did some "tweaking" which included respacing the bb and dremelling off the inner chainring flange to clear the chainstay. With a 113 Stronglight bb, I'm within a mm or 2 of a spot-on chainline with the ring in the outer position - which just looks so much better.

Looks good, stiff as a brick - at least as far as my old legs can tell - and at $20 a bargain to boot.


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## jmlapoint

Dave Hickey said:


> +1..true track cranks are round and don't have tight and loose spots during a revolution... I've yet to have a road crank/ring that is truly round
> 
> My 3Rensho is using a Dura Ace track crank and ring and a Phil Wood cog...It is super quiet and there are no tight/loose spots..


+1 for Track Cranks.
My converted Track Bike has Campy Record Pista 144 BCD Cranks and Campy Track Chainring with Izumi Mod-V Chain and it is still very smooth and round`.


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## roadfix

I may be way off on this but the larger the BCD, the lesser margin for machining error, among other things...


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## FatTireFred

Dave Hickey said:


> +1..true track cranks are round and don't have tight and loose spots during a revolution... I've yet to have a road crank/ring that is truly round
> 
> My 3Rensho is using a Dura Ace track crank and ring and a Phil Wood cog...It is super quiet and there are no tight/loose spots..




the rings are round... the crankarms simply don't have a shoulder for an inner ring and (usually) have a larger bcd (144), limiting the choice of rings to >42 or something like that... and are often shorter 

if you use a road crank you'll often need to use the inner ring position for the right chainline (ugly to some), or use a guard on the outer ring position (ugly to some), or monkey w/ bb spindle length if you want to use the outer position




.


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## David Loving

Me, I'd go with the 105's on eBay and get used to it.


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## roadfix

Early 90's C Record road cranks for the sexiest conversion cranks!.........just .because I've got them on my SS conversion.


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## Johnny LaRoux

David Loving said:


> Me, I'd go with the 105's on eBay and get used to it.


Ya, that's the way I'm leaning also, judging by the posts here...I don't really want to drop the $$ for a "real" track crank right now, and I'm currently running my 7700 Dura Ace crank with a 109.5 octalink BB, and the chainline is dead-on, and pretty quiet also. I've just had a couple of scrapes with the 175mm cranks, and would feel much better with 165's or 170's on there.

Saves having to get a new BB etc.

Thanks to all, for you input.


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## Alx

roadfix said:


> I may be way off on this but the larger the BCD, the lesser margin for machining error, among other things...


Is there any references or truth to this or to the comments about track Chainrings being more round than road? Cause I find it hard to believe that a machined piece of metal has an oval shape "designed" into it because its not a track part, short of the cheesy biopace rings of course. I guess I'm at a loss believing that manufacturers of chainrings manufacture a part that should be perfectly round yet they program their machines not to be as precise????


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## FatTireFred

Alx said:


> Is there any references or truth to this or to the comments about track Chainrings being more round than road? Cause I find it hard to believe that a machined piece of metal has an oval shape "designed" into it because its not a track part, short of the cheesy biopace rings of course. I guess I'm at a loss believing that manufacturers of chainrings manufacture a part that should be perfectly round yet they program their machines not to be as precise????




I don't think it's machining related to bcd, prob more likely a higher standard of production and QC... imperfection is more tolerable when you have a tensioner/derailleur

see the first para under sugino http://www.peterwhitecycles.com/fixed.asp
there are prob other references out there (s. brown, etc), pretty sure I first saw it mentioned in a book


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## zigurate

I'm probably also getting some Dura Aces for me.



Dave Hickey said:


> +1...Agreed and track cranks are usually 144 BCD and are very expensive...
> 
> You are usually going to pay $200-$300++ for a quality track crankset...and that doesn't include a bottom bracket..
> 
> Check eBay for used Dura Ace 7600 cranks...They are equal to the Sugino 75 yet the aren't as popular with the fixie crowd..
> 
> This guy sell used Sugino 75 and Dura Ace 7600 crank arms and rings... I've bought from him many times...He takes paypal
> 
> http://njs-keirin.blogspot.com/2007/11/njs-cranks.html


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## PeanutButterBreath

Cutting tools wear and have to be replaced, which adds production cost. If the market price of the item (or function) doesn't justify the extra expense, it is more cost effective to loosen tolerances and let the tooling ride that much longer.

QC costs are also going to be lower.

Also, if you are working in a small niche, you have to account for less variation across manufacturers. A low-cost aftermarket chainring like a Dimension has to account for a vast array of cranks of varying quality. Better to make them with enough wiggle room for maximum compatibility.

With track stuff, the market and function justify the higher price of making things to a tighter spec.


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## bikeman68

To Fat Tire Fred
As a guy with machining exp, i can tell you that the manufacturers of track crank really hav eto go out of the way to ensure totally concentric spider seats and chainrings. It cost more to do this.
The shimano road cranks with their matching chainrings will be about .3 or .5mm out of round, and this is considered fine for road bike use, even on a DA equipped bike. .5mm out of round is no fun on a track bike.


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## bikeman68

Hey Fixie Guys
I race on the track at a more grass roots (literally, grass infield, hehe) old track, Kissena in Queens.Anyhow for a rider on a real Budget,look at the picture of the spankin new SOMA, it has the 80 buck track crankset with 144mm bcd, and made at a taiwanese component manufacturer under a few different names,(Andell) in 165mm or 170mm.It has only one outside chainring position, so it is a track crank.Roundness is fair, not excellent, but unless you are doing the Pro/Am night at the elitist Velodromes, this ones fine. If you need sizes like 167.5, 172.5, 175, then you need to get the Miche track cranks


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