# STX crank question



## patrase (Sep 20, 2007)

Hi

I have a 1994 Diamond back ascent, it has an stx crank and i want to get a new 32 tooth chainring to run singlespeed.

The problem is that the middle ring has a 58mm bcd - it bolts to where the granny ring resides

So there dont seem to be any obvious chainring replacements

If i cant find anything i will either buy replacement cranks or grind down the old ring and bolt a new one where the big ring bolts up

What was the solution back in the day?


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## MendonCycleSmith (Feb 10, 2005)

patrase said:


> What was the solution back in the day?


Not that I heard of. They were from a time period where they were trying to cut some costs, and while the STX group was a fine entry level, trail worthy group, I'd say either grind it, or scrap it. Any significant effort is unwarranted, as you can get a modern replacement, with a BB, and replaceable (therefore easily SS-able) rings for about $40.


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## DeeEight (Jan 13, 2004)

The solution was you ordered the chainrings from shimano, which is what they intended when they made the middle ring bolt to the inner holes (the big ring bolted to the middle ring).

Same thing SRAM is intending for the XX group when they changed the 4-bolt patterns for the small and big rings to something nobody else uses. Or ControlTech with their 2-ring cranks which use a 94mm bolt circle... in a 4-bolt pattern (smallest tooth ring in 94mm is 29T).


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## Zanetti (Sep 18, 2005)

patrase said:


> If i cant find anything i will either buy replacement cranks or grind down the old ring and bolt a new one where the big ring bolts up


Be sure to measure the outer ring BCD. I'm pretty sure it's 95mm instead of the industry standard 94mm for compact/micro-drive cranks. Shimano strikes again.


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## gm1230126 (Nov 4, 2005)

There were two STX cranks the STX and the STX-RC which had the "Chromica" colored chainrings. From what I recall the low end STX crank was the same as the Alivio crank with riveted chain rings and a lighter arm... hence not replaceable but a plug and play throw away crank. The STX-RC crank had replaceable rings. Alloy outer and steel middle and inner from what I recall. What the heck do I know anyway I just wrote specs for a bunch of bikes that had them back in 1994. Hit the link below and scroll down it will give you some insight. Your best bet would be to pick up a low mile one off the bay and do your own ring swapping or plug and play of the crank arm. I just sold one on the bay a week ago. See pic

http://www.bikepro.com/products/shimano_tables/shim_frtchnwhl_table.html


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## WEBERTIME (Feb 4, 2004)

gm1230126 said:


> There were two STX cranks the STX and the STX-RC which had the "Chromica" colored chainrings. From what I recall the low end STX crank was the same as the Alivio crank with riveted chain rings and a lighter arm... hence not replaceable but a plug and play throw away crank. The STX-RC crank had replaceable rings. Alloy outer and steel middle and inner from what I recall. What the heck do I know anyway I just wrote specs for a bunch of bikes that had them back in 1994. Hit the link below and scroll down it will give you some insight. Your best bet would be to pick up a low mile one off the bay and do your own ring swapping or plug and play of the crank arm. I just sold one on the bay a week ago. See pic
> 
> http://www.bikepro.com/products/shimano_tables/shim_frtchnwhl_table.html


It was STX and STX SE (shiny finish). Both used the odd-ball bolt on method mentioned in earlier posts. STX RC came out in 96:skep: with the 4-bolt pattern, although they did make a few STX-RC in 5 bolt.


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## gm1230126 (Nov 4, 2005)

WEBERTIME said:


> It was STX and STX SE (shiny finish). Both used the odd-ball bolt on method mentioned in earlier posts. STX RC came out in 96:skep: with the 4-bolt pattern, although they did make a few STX-RC in 5 bolt.


Ahh check that....STX-RC was out in 1995 http://datenbanken.freepage.de/cgi-bin/feets/freepage_ext/41030x030A/rewrite/traut/SHIMANO.html#95
Some of us were working specs with the stuff in late 94.


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