eyemkeith

Hi all.

I'm looking to replace the crankset on my 1992 XO-2 because at least the two big chain rings are pretty beat up. The previous owner put a Exage 500 CX crankset with Shimano SG E chainrings in a 50/40/30 triple. I'm not sure if this was original equipment or not, but I tried looking for just the chainrings and, oh boy, what a goose chase that has become.

So I'm thinking of just swapping out the crankset enitrely, but I'm unable to shell out $150 or so for a Sugino XD. Plus, I've kinda gotten used to the bigger chainrings anyway. I happened to find a SunRace setup that looks decent and it's in my price range, which is to say it's cheap. But I thought I'd put it out to those who know more. Is there anything wrong with this crankset?

https://smile.amazon.com/Sunrace-FC-...gateway&sr=8-6

Big thanks in advance!

Keith

Bill Kapaun

The 93 lists a Shimano 500CX, 30/40/50 teeth. (doesn't go back to 92)
https://www.bikepedia.com/QuickBike/...spx?item=41493

I would assume any 130mm BCD rings should fit.

eyemkeith

Can I do that?

See, this is why I ask first. I don't know the first thing about wrenching on anything. If I hold a tool, there's a 50 percent chance it ends up in my eye.

If I can just get 130 bcd chainrings, I'm good. Do they have to match, like brand and type, for all three or does that matter? It does seem the more economical way to go.

Bill Kapaun

"Matching" rings should shift as designed, since they have ramps & pins designed to assist the shift. They kind of "sync" together.
Non matching may be a bit sluggish to no perceptible difference.

Are you sure your rings are bad?
New rings will appear to have short/broken teeth, chips, gouges etc. That's to help the shift.
They are usually spaced equidistantly, so if every "broken" tooth is n teeth apart.......

OR
How do the old rings work? they may be fine if they don't skip.

Andrew R Stewart 

- I suspect the crankset does have a 130/74mm set of bolt circles for the rings.

- I suspect the front shifter is friction so as long as chain/ring spacing/clearances are good the shifter won't mater.

- I suspect the OEM rings are of a very early shift aided design. Modern rings might well shift nicer.

- Of course since so much of front shifting performance is the rider's technique... Andy

bikemig 

The sunlite crankset has steel chainrings; I'd avoid it.

Chainrings are available for your crank.

The exage crankset is original equipment. Bridgestone catalogs are available online

https://www.sheldonbrown.com/bridgestone/1992/1992.pdf

eyemkeith

Thanks for that, mister. I appreciate it.

eyemkeith

Again, I did not know about that. I was going on the assumption that broken looking teeth were just bad, but it does shift just fine. I'm just going to leave them alone until they break, I've decided.

Thanks so much for your help. And everyone else too. This is why I ask these things first. You guys have saved about $100!