RADBMX.CO.UK
Technical & Reference Section => Tech and Restoration => Topic started by: Avro on January 12, 2017, 01:47 AM
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I posted this on the museum first as the parts are primarily fitted to a Huffy model but open it up to here. I am trying very hard to keep an open mind but it is becoming difficult!
This is a question regarding the Shimano SX Z2 chainwheels fitted to the Huffy Pro Thunder (possibly other bikes).
I have a quirky frame that I am hoping to fit quirky parts to, including the Z2 twin chainwheels, just for the hell of it.
I have bought most of the components, enough to get going but I have come across a problem. The outer 40T chainwheel appears to have a number of broken teeth. The seller insists that they are not broken but ramps to assist gear change. I want to give the seller as much latitude as possible but I have found a picture of the same chainwheels with a full compliment of teeth. I have also found another picture of a chainwheel also missing teeth. That said there are very few pictures available.
Having big gaps, and what certainly looks like broken teeth on the chainwheel does not look likely to be factory. To assist gear change....come on! But I am never one to dismiss something out of hand. It would be great if someone with this gear set up could post a picture of their chainwheels. Opinions welcome, I'm I being too kind!
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I know nothing of these but it is unusual in the fact that the missing teeth are diametrically opposite each other so I would say intentionally not there rather than broken off :-\
Just my thoughts - i'm sure someone on here will know the correct answer.
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Hi Peter,
Yes these are supposed to be missing teeth....helps aid the transfer of chain from 1 sprocket to the other when pushed/pulled by the front derailleur
I have spent many hours researching this setup for my shimano Builds... actually quite jealous you have these lol... does your frame have the hole on the dropout for the rear derailleur ( it hooks over the rear spindle then secures with a 2nd fixing to the drop out) if not you may need to drill one
What components do you have so far to get this going
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Yes, a little bit of research and the 'missing' teeth are indeed supposed to be missing. Still looks odd!
I do not actually intend to use these chainwheels as they weigh a ton and they will be tricky to fit them to the intended bike.
I plan to use 44T and 36T alloy chainwheels with a conventional five arm spider, should be straight forward I think. I am sort of going for the Bobby Encinas look without the DX cranks unless someone wants to donate a set of those, they are not worth much, no one wants them, honest.
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Simon, regarding the rear derailleur, or more correctly rear chain tensioner: there is no need for a drilling. The bolt you see actually mates to a semi circular boss which locates into the wheel spindle slot, fortunately I have this spacer.
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I have all the parts required except a cable but that will be easy enough to make.
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I am liking this..... :daumenhoch:
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I think that's the first pic I've seen of a bike with DX cranks where they actually suit it
Although I love the look of them (as objects in their own right) for some reason to my eyes they usually look horrible as soon as they're fitted to a bike
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I've got a NOS Shimano SX Chain Tensioner if needed ;)
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Interesting stuff! :daumenhoch:
I think that's the first pic I've seen of a bike with DX cranks where they actually suit it
Although I love the look of them (as objects in their own right) for some reason to my eyes they usually look horrible as soon as they're fitted to a bike
My thoughts exactly! For that reason (ignoring crazy prices), I've never considered them for one of my bikes, but then I do like a good ol' opc!