I'm trying to restore a 10-speed Dawes from the 70's. The pulleys on the rear derailleur-A Simplex Prestige (red badge)-are completely worn. I'm wondering whether it makes sense to just replace the pulleys (from what I've seen online Sun Tour pulleys are compatible with these), find a Simplex Prestige online or get a new derailleur altogether. From what I've read, the derailleur I have is not the most long-lasting, with the plastic parts and all. Mostly what I'm asking is how do you know what parts are compatible?

You read correctly, SunTour pulleys WILL work in your Simplex derailleur. Spray some penetrating lube (I used Amsoil MP) to clean up the derailleur and grease liberally in areas that need it including the new bushings (I used Amsoil Synthetic Lithium #2).

Well...I mean, you pretty much nailed it ALL out in your paragraph. You can replace the pulleys; find a Simplex Prestige; Modern Derailleur (THIS WILL/MAY REQUIRE MODIFICATION IF YOU HAVE BRAZED ON DROPOUTS!!!! Do you?) I'm still using my Simplex Criteriums with 93km on it after the rebuild. The only issue I have is keeping things in adjustment, they become whacked after 10km or use and I suspect the 37 year old shifter cables are suspect .

According to many here I should have derailleurs and the Simplexes are supposedly going to disintegrate after ten years. I expect another five or ten years at least.

Thanks for the quick reply.

I think I'm going to go with this guy as it appears to be the cheapest option-$25 for NOS:
https://harriscyclery.net/product/sim...illeu-2416.htm
I tried looking on ebay but the pulleys seem to cost as much as a new derailleur.
Any other good places to find pulleys or derailleurs?


By the way, dropouts are not braze-on.

You'd have been much better off buying an old Suntour on eBay. Any old Suntour.

If you want to look-up some SunTour pulleys, I may have a SunTour GT NOS subtract pulleys that you can PM me for.