Chain and gear thickness
 

Hi. I've got some silly basic questions regarding drivetrains and width compatibilities. My new bike is a Tricross Singlecross (singlespeed); it came with a KMC Z-510-HX chain, which is described as a 1/8" chain. I'm in the process of building a respaced Alfine hub into a wheel for it. I'd like to repurpose the original wheel for my old Nishiki road bike, if possible.

Now for the questions: (1) Will any cog work with this chain (for the Alfine), or need it be a "wide" cog (i.e. 1/8-specific)? I ask this because i have an old cog for the previous-generation Nexus8 and it noticeably narrows at the teeth, but they are both said to be compatible with the Alfine. (2) Will the existing wheel/freewheel work with any other chain (e.g. can i put the old wheel on an old 12-speed)? (3) Can an 1/8" chain work with a chainring intended for a 6- or 7-speed (e.g. if (2) won't work, will it if i change the chain to a wider one)?

So, yeah, basically, can 1/8 chains stay put on gears intended for narrower chains and do the job just as they ought? I guess that sums it up.

Thanks for your help.

It's like this;

a 1/8 chain will work with any sized drive train (3/32 or 1/8)

3/32 drivetrain components will work with any sized chain.

Any other combination and the chain and drive component must match sizes.

most geared bikes cannot use a 1/8" chain because of the lack of spacing between each of the rear gears on the casette/catridge.

with technology pushing 11 in the back chains are thinner than they were

Originally posted in the Bike Forums Singlespeed and Fixed Gear forum...

So that's not really of much concern...

Ah, i looked at some 3/32 chains and they are calling them 6/7 speed chains. That makes more sense now. Thanks. So the internal (width) spacing on 6-speed chains will fit over gears also intended for 1/8 chains. It's the 8-10 speed chains that aren't compatible.

So, that means that the 16 tooth freewheel in the singlespeed wheel should work with the chain on the 12 speed, and the cogs for the Alfine are all going to be narrow enough for either a 3/32 or 1/8 chain.

I think you have it backwards.

First, it's easiest to deal with single speed specific parts. You'll be able to find 3/32 and 1/8 chains from any LBS that are single speed specific, which removes the confusion of trying to figure out how many gears works out to what chain width.

Second, it's a 1/8th chain that works with either 3/32 or 1/8 drivetrains. A 3/32 chain will only work on 3/32 components. Basically, the chain can be bigger than the cog it goes on, the cog can't be bigger than the chain or the chain won't slip over it.

If you're talking about non single speed bikes, you need the chain that matches. A bigger chain will fit over the cog, but will probably get jammed between the next largest and smallest cog if it's too wide.

D'oh! Not quite backwards, but i didn't know that a 3/32 chain comes in ss-specific design, and also missed one implication from your first post. Thanks for your patience.

I have resolved the sprocket confusion: i have one Shimano sprocket:
http://sheldonbrown.com/harris/sturm...ges/HUH056.jpg
and one Sturmey-Archer sprocket:
http://sheldonbrown.com/harris/sturm...ges/hsl717.jpg

According to http://sheldonbrown.com/harris/sturm...html#sprockets, the latter is 1/8" only, while the Shimano one is 3/32, which explains that particular confusion.

So to use my singlespeed wheel with (presumably) a 1/8" cog (i say presumably because they put the 1/8" chain on it stock) on my 12 speed, i'm going to have to put a singlespeed 1/8" chain on the biggest chainring and run it as a SS (which is what i'd intended, but wasn't sure if it would work), right? I realize that's super ghetto, but i need a beater bike and don't have any use for the ss wheel after i build up the Alfine, and the 12 speed rear wheel died...

Let me also hijack my own thread and ask if anyone knows about the quality of the Shimano vs. Sturmey-Archer sprocket, or of any better third-party models. This is for the IGH, so maybe i need to take this to a new subforum. The SA sprocket is a dull, dark grey color. The Shimano sprocket is a shiny chrome color.