How hard (moreso costly) is it to put a modern drivetrain on a vintage mtb?

[Tootyred]

How about this....

Bicycle Marin Bear Valley Retro 20in for Commuting/Touring Thorn Bar Tortec Rack | eBay

I added a nice Fabric saddle, Sks mudguards, Thorn riser bars, Tortec rack, Koolstop brake blocks and Schwalbe Landcruiser Plus. Set up as Commuter/Tourer. I have recently stripped it down, cleaned and serviced all the parts.

www.ebay.co.uk

Guards and rack off and your ready to go. If you want flat bars, just ask here...we all have piles of them blocking up cupboards!

 

[retrobiker273891]

How about this....

Bicycle Marin Bear Valley Retro 20in for Commuting/Touring Thorn Bar Tortec Rack | eBay

I added a nice Fabric saddle, Sks mudguards, Thorn riser bars, Tortec rack, Koolstop brake blocks and Schwalbe Landcruiser Plus. Set up as Commuter/Tourer. I have recently stripped it down, cleaned and serviced all the parts.

www.ebay.co.uk

Guards and rack off and your ready to go. If you want flat bars, just ask here...we all have piles of them blocking up cupboards!

Don't use ebay.

 

[Guinessisgoodforyou]

In response to the original question. Turns out way more difficult than it needs to be.
Experienced people offer you advice and you argue the toss with them? I genuinely hope you find what you are looking for.

 

[nstarmore]

I genuinely hope you find what you are looking for.

Likewise, never seen a new member dominate the forum so much in 1 weekend

 

[Imlach]

Likewise, never seen a new member dominate the forum so much in 1 weekend

And to think there's 273890 more out there...

 

[Tootyred]

Well.....it fills my time whilst the relatives are here...

 

[Imlach]

On a serious note I too want you to find something that works for you. I know what it is like to think this is exactly how i want my bike to be set up and I have sunk good money into projects which were a success but with hindsight I could have done it more economically. I feel like it is pretty clear that a full bike with the right components, to not have to do any major adjustments is the key. There's many ways to get into the hobby and none of them are wrong. But you're doing very intense mental gymnastics about something rather marginal and easily attainable.

 

[Imlach]

I also fear your rigidity may make it harder, not able to collect if urban location, not using any of the major commerce platforms and not doing PayPal is fair enough but obviously restrictive.

 

[highlandsflyer]

On road or off road? You say gravel, so I found one or two fulfilling your criteria then noted you don't like going to cities.

How about giving your broad location, to see if anyone can help?

 

[klunkrider]

Have only scanned the thread so may have missed something but...

Microshift 11 speed mini group £90. https://sportandleisure.com/products/microshift-xle-x-shimano-11-speed-drivetrain-groupset-11-42t?

Leaves £310 of a £400 budget to find a bike with (or upgrade to) an 8+ speed HG freehub.

I'd look for a bike with (or again, upgrade to) 104bcd cranks that you put a cheaply and readily available narrow wide chainring onto.

I see chat about 22t chainrings but with a 42t at the back you do not need that size of ring. I don't think I could maintain the cadence required to keep a bike upright with 22:42 gearing for very long and you'll find the limits of grip long before you run out of gearing even with something a 32t ring.