Bicycle Mechanics - General Compatibility Question - older bike

Hi all,

I have an 80's Centurion Ironman that I purchased 18 months ago. It has a hodgepodge mix of components and I am wondering from a functionality standpoint if it is sound. From reading around these forums and Sheldon Brown's website, I *think* this setup works but I would like some insight.

Here are the specs:
RSX Triple 8spd Shifters, Double 53 39 Chainrings, some sort of Shimano FD (sticker came off), "9 Speed" Shimano Chain, Shimano 9-speed Tiagra RD, Shimano "8 Speed" HyperGlide 13/25 Cassette (was a 9 Speed Cassette but smallest cog was removed), and a Shimano HyperGlide Freehub Body.

How well will this perform? Are there any recommended upgrades/changes?

-Brent

So you're talking about an "8 of 9-speed" set up.

You need a 9-speed shifter to match the 9-speed cassette spacing and I'm not so sure about the lockring staying tight against a 2nd position cog.

doesn't make sense to me remove the last cog when you could simply set it up normal and the last click would probably stop right at the 2nd to last cog anyways. At any rate, your probably better off just buying a new 8 speed casette and then I don't see any reason why it shouldn't perform fine for you. RD's are pretty much interchangeable, I don't know how different 8 and 9 speed casette spacing is but putting on an actual 8spd casette could only help matters. I'd probably put a new chain on at the same time the two combined would probably be about $50. It's far cheaper to do this than to get a 9speed shifter.

So you're talking about an "8 of 9-speed" set up.

You need a 9-speed shifter to match the 9-speed cassette spacing and I'm not so sure about the lockring staying tight against a 2nd position cog.

Stupid of me, I forgot to mention what speed shifter I have! The Tiagra RD is a 9-speed. I was on my way out the door when I posted. Modified the original post to reflect this.


doesn't make sense to me remove the last cog when you could simply set it up normal and the last click would probably stop right at the 2nd to last cog anyways. At any rate, your probably better off just buying a new 8 speed casette and then I don't see any reason why it shouldn't perform fine for you.

So its unanimous that I should just leave the last cog on the cassette. It won't hurt since the cassette with 9-cogs doesn't extend beyond the freehub.

Thank you for the replies!

I must be a bit thick, but I don't understand your post. You've been riding this bike for 18 months or so.

Why are you asking a bunch of strangers who've never seen it to speculate on whether it'll work or not? If it's working, no need to post, if it isn't working what are the issues?

BTW- if it is working, you can probably make it better if you throw some dough at it, but there's a limit to what you can do with a bike of it's original quality and current age. I suggest that if it works you enjoy it as is, and if thare's a particular issue you deal with it and only it before you make a decent ride into a money pit.

I must be a bit thick, but I don't understand your post. You've been riding this bike for 18 months or so.

Why are you asking a bunch of strangers who've never seen it to speculate on whether it'll work or not? If it's working, no need to post, if it isn't working what are the issues?

BTW- if it is working, you can probably make it better if you throw some dough at it, but there's a limit to what you can do with a bike of it's original quality and current age. I suggest that if it works you enjoy it as is, and if thare's a particular issue you deal with it and only it before you make a decent ride into a money pit.

Good question. I rode it for a few months last summer into fall, and the shifting was a little slow. Where the shift cables exit my brifters, they come out at fairly sharp angles (not flowing and rounded). When I was in my LBS at the end of riding season last year, one of the guys in the shop made that observation. I bought some new cables and housing as they look really old, and I am going to clean the bike up real nice. I am just hoping that I didn't overlook anything component-wise before I put time into it.

So its unanimous that I should just leave the last cog on the cassette. It won't hurt since the cassette with 9-cogs doesn't extend beyond the freehub.

Thank you for the replies!

!?

Good question. I rode it for a few months last summer into fall, and the shifting was a little slow. Where the shift cables exit my brifters, they come out at fairly sharp angles (not flowing and rounded). When I was in my LBS at the end of riding season last year, one of the guys in the shop made that observation. I bought some new cables and housing as they look really old, and I am going to clean the bike up real nice. I am just hoping that I didn't overlook anything component-wise before I put time into it.

Just replace the cables and housings, clean everything up, relube the chain, and see how big a different that makes. While changing the cables and housings, it's a good opportunity to make sure all the settings on the derailleur are optimal. If you have significant shifting issues after that, then it may be time to think about changing components.

Your shifters need to match the cogset... removing one cog from a 9 speed cassette and running it as an 8 speed is a cludge and won't give you optimal shifting as a 9 speed shifter pulls less cable than an 8 speed shifter.

The derailleurs don't care how many speeds you run and 9 speed chain works fine on 8 speed blocks although 8 speed chain is much less expensive when it comes time to replace it.

Correct...you have an 8-speed shifter. Buy 8-speed or 7-speed SRAM 730/830/850 cassette. They all have the same spacing per my digital caliper. I run 730 or 830 interchangeably. Also buy the 8-speed chain, which is cheaper and last longer than 9-speed. Wait for the Nashar tandem chain to go on sale at 1/2 price, then load up. You'll pay about $7 per use. This chain is good for 4.5K miles before reaching the recommended replacement interval. The key is to keep the chain lubricated and reasonably clean. Those RSX shifters are very smooth if properly adjusted. No need to upgrade.

The 8-of-9 thing refers to putting 8 cogs of a 9 speed cassette on a 7 speed freehub (It also works with 9 out of 10), which is shorter and will not fit the full cassette - frame spacing is also smaller. You need a 9 (or 10) speed shifter to match the cog spacing - the reason this lets you fit more cogs is because they are closer together. An 8 speed shifter will not work on an 8-of-9 setup, and a 9 speed shifter will not work on a 9-of-10 setup.

When dropping a sprocket to, for example, use a 9s cassette as an 8s on a narrower freehub body, the key is to match the shifters, to the spacing, not the number of sprockets. 9s spacing calls for a 9s shifter, 8s spacing calls for an 8s shifter, etc. regardless of the number of sprockets actually used.