Updating old bike frame with newer parts
 

Steel frame is in excellent shape as well as fork.

Seeking ideas, options to rebuild using used newer parts.

If original rims are ok, is it better to used those or consider 27.5 or 29ers?

Basically sitting here now with naked frame wondering what to do and where to start.

Clean all the old parts...1

Put the bike back together...2

Replace with newer parts as you can, should or want to...3

Need a lot more information about the bike before giving any advice.

road, mountain, wheel size, brake type, rear spacing.....picture picture picture

Most C&V mountain bikes use cantilever brakes. This can make changing wheel size a serious challenge.

A good frame can be a lot of things, and it doesn't have to be permanent if you like to tinker. There are a few limiting factors like brake reach and tire width, but it's probably best to start with the type of riding you envision for that bike. Also, yes, pictures please.

It is always a good idea to at least consider reusing the original parts:

• it keeps the bike original, which is generally a good thing from a resale value point of view
• they were chosen by the original builder for a reason, and unless that reason was cutting costs, it is worth at least looking into
• it saves the environment from having to produce new ones

For me the most important thing is FIT FIT FIT if you haven't ridden it much or at all don't dive in on upgrades before doing so (ask me how I know :D) so clean up what you have put it back together lube it replace the consumables -tires chain bar wrap brake pads etc and then ride it ALLOT ( short long hills flats) and note what you like and don't like, tweak it etc and then think about upgrades or selling it on and finding something that does fit YMMV.

Depends. If the frame was built to use 27" wheels, there are only a couple decent quality options for tires, Panaracer "Paselas" and Swift "Sand Canyon." If there are others, I'm not aware.

You may be able to use 700C wheels, but long reach brakes may be needed if the frame was built for 27". 29er rims are the same ERD as 700C, but tend to be wider. Check frame clearance.

27.5 rims are the same as 650B, and are smaller diameter than 700C (27"=630mm ERD, 700C/29er=622mm, 27.5/650B=584mm), so your brake options may be limited, if at all available.

Gatorskins and Schwalbe Marathons also come in 27". I've never tried the Gatorkins but Marathons are pretty durable though not lightweight.

Bare frame? Where to start? Find a donor bike. Building it up a part at a time is very expensive. Transplant from a donor bike is typically the cheapest option. I upgraded my well worn and tattered 1988 Cimarron with a $65, lightly used, top of the line MTB from another brand.

27 x 1.25 are 630g. Yeah.... Heavy with that heavy protection gel down the middle of them.

Easily done.
Readily addictive.
It's a wonderful slippery slope to mobilemoving magnificense .

Ultra sport II is supposed to be a nice tire and was even tested for rolling resistance by some bike tire geeks and it tested well,

https://www.biketiresdirect.com/prod...UaAtgLEALw_wcB

Without more information, beat me to it. This way would be the most economical.
The previous advice is also useful, but there are many specific attributes of the frame that can guide or provide hurdles to building a bike.

@BridgestoneTBMB you'd be way better off sticking to one thread for this bike project, rather than eight. Less confusion for the people who would earnestly like to help you out. :p

Yep, I've got 27 x 1-1/8 Ultra Sport tyres on two of my bikes. Much better ride than Gatorskins, and they do seem to roll well.
They are generous in size though, and the 1-1/8 are as large as I can fit to allow clearance for mudguards.