Indyv8a

I tried to ask this before, but I don't think the question came out clearly. I have an early 80's Austro Daimler Olympian. It has the standard front derailleur from Huret, and a Suntour GT rear. The wheels are shot, pitted bearings, bad rims, etc. so I am planning on replacing them with new wheels. I tried out the 8-speed rear from my son's Sora equipped bike. Width-wise it fit fine, no spacing or anything else needed.

My question: I could not get the current derailleur to shift across all 8 cogs. It only went across the middle six. Can I adjust this out? What parts do I need to get this working? Will I need a new derailleur? Will an 8 speed chain work with the original front chain rings? Recommendations?

I am flirting with the idea of slowly building this up to an STI setup. Budget-wise that will be a slow process. Skills-wise, I am probably my own worst enemy, but I'm willing to try.

anti.team

It's not too surprising that it wouldn't work, but you might not be completely out of luck.

Did you adjust the limit screws? That would be the simple solution.

If so and still no luck, don't despair. You may need a new rear derailleur but you can use almost any modern RD. Something like a Shimano 105 or even Sora would be fine and you could probably pick one up for under $20.

Don't worry too much about chain compatibility with the front chainrings. Your front chainrings don't really care what chain you have (there are some exceptions, involving 10sp chains) but you should be fine. I recommend the SRAM PC-850 (formerly PC-58), it should work with just about any 8sp setup.

dabac

You probably can. There are two screws that limits the der range of movement. Start by backing them out and see what happens. You might have to clamp the shifter cable a little longer in/out too.

Probably none.
Probably not until you go to indexed shifting and maybe not even then.

Can't promise that it will, but the odds are really good.