Retrofitting a modern drivetrain on an old bike, caveats?
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Retrofitting a modern drivetrain on an old bike, caveats?
I have this bike in a size that doesn't fit me: https://bianchiusa.com/05_bergamo.html That's a 7-speed cassette, a 3-speed hub, and a single chainring in the front.
And a 1983 Ross Grand Touring 12-speed. It's your standard 80s road bike with drop bars, downtube shifters, and mostly Altus components.
I would like to take drivetrain components (Wheels w/ internally geared hub, Crankset, Chain, Derailleur, shifters, and cabling), off the Bianchi and retrofit them onto the Ross.
I am not an experienced mechanic and would like to know what problems I'll run into ahead of time. I have read a little about derailleur adjustment and limit screws but have never actually done it.
I know that I will need to have the shop do the crankset work for me, as I don't have the tools. And I am going to have to get a HubBub adapter to run that grip shifter on the drop bars (Unless there is another way??).
Is there anything else that I need to look out for?
Also, bonus question: Would it be possible to leave the double chainrings on the Ross and run this as a 42-speed bike? Mostly just a silly academic question.
And a 1983 Ross Grand Touring 12-speed. It's your standard 80s road bike with drop bars, downtube shifters, and mostly Altus components.
I would like to take drivetrain components (Wheels w/ internally geared hub, Crankset, Chain, Derailleur, shifters, and cabling), off the Bianchi and retrofit them onto the Ross.
I am not an experienced mechanic and would like to know what problems I'll run into ahead of time. I have read a little about derailleur adjustment and limit screws but have never actually done it.
I know that I will need to have the shop do the crankset work for me, as I don't have the tools. And I am going to have to get a HubBub adapter to run that grip shifter on the drop bars (Unless there is another way??).
Is there anything else that I need to look out for?
Also, bonus question: Would it be possible to leave the double chainrings on the Ross and run this as a 42-speed bike? Mostly just a silly academic question.
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Is the spacing across the rear hub the same as the spacing across the frame? This has changed over the years and will be critical to the conversion.
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On eBay I saw 126mm spaced rear hubs. Intuitively that seems like it could be pursuaded into either 130mm or 120mm spaced rear drop outs.
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I suspect that the 83 Ross frame is 126mm between the dropouts and the SRAM Dualdrive hub from the Bianchi is a 135mm device. This could be a stretch without cold setting the frame. Read Sheldon Browns Frame spacing article.