I've searched and read multiple threads about how to convert from 27" to 700C, but something is still not clicking with me on how to do this.

I have a 76 Motobecane Grand Record that still has the original Mavics laced to Lux hubs. I love the bike but want to upgrade it's wheels and other parts to make it a good longhaul commuter.
I belive my brakes have enough reach to accomidate the 700c, but I'm not sure weather I need to stick with the 7speed freewheel or move to a casette set up. The dropouts are spaced at 126mm, so what options do I have?

If the gearing suites your needs, leave it alone. A drivetrain upgrade could cost more than it's worth to you. You could replace the freewheel with another 7-speed if needed and maybe a new chain.

Whats wrong with the 27" rims? If nothing then why not keep them on the bike? There are some manufactures coming back to making 27" tires again because there's a ton of those wheels still out there. Continental came out with a Gatorskin 27" tire which is the best tire available currently for a 27.

As far as converting the bike to a 700c rim, the only problems you will have is 1) whether or not the calipers will adjust to reach the rim. I have a 84 Trek 660 that I was able to adjust the calipers due to having medium reach calipers which gave me just enough reach for both size wheels. 2) problem is the rear spacing. All I had to do with my bike was to have a washer installed on the freewheel side and have the rim dished slightly differently then normally would have to be done...but I had the original 6 speed cluster replaced with a 7 speed cluster and it was for that reason I had to have the washer and the rim dished differently which they had to do anyways since they were new rims.

I would avoid the cassette nightmare, the cost will be much higher and you will gain nothing. They would have to cold spread your stays to accept the new hub with the cassette, switch to different derailleurs and thinner chain (which doesn't last nearly as long as the older wider chains). You can keep the downtube shifters (or barcons if your using those) unless you want briftors but there goes the price up again. Having never done that procedure before I may be missing some items or not giving the right info on what is needed to it.

I have several older bikes and have no intentions to converting them to cassette, I'm happy just the way they are.

I would love to keep the bike in 27's with the seven speed free-wheel, I just hate how bad steel rims perform in wet conditions. My ideal set up would be using my original hubs and lace them to a set of modern 27" wheels. Do you know if anyone makes alloys with a 36hole pattern?

Oh and BOOMER SOONER Al1943

27-inch pre-built wheels:
https://www.bikepartsusa.com/bikepart.../wheel-27_inch
27-inch rims:
https://www.bikepartsusa.com/bikepart...ry/rim-27_inch

Note that rebuilding your hubs with aluminum rims would probably cost more than buying pre-built wheels and having them tensioned and trued by a good wheelbuilder. The last step is recommended since cheap wheels are usually machine-built and not tensioned properly.

KinLin 5ALM true classic 27 x 1 1/4

Silver, Black or Polished in 36H.

=8-)

Awesome! Thanks for the advice!

You can also find new old stock (NOS) 27" rims on E-bay for usually less then Bike Parts USA. Someone sold a lot of 10 rims brand new NOS rims for less then $150 last year. Note, these were just rims no spokes or hubs. My point is the old stuff can be found brand new yet and cheap

I think good alloy rims and double butted 2.0-1.8-2.0 spokes would make a very good improvement. Steel rims are just too heavy.

Boomer Sooners. My son is a big OU fan, I'm still loyal to the Razorbacks.

Steel? Who said anything about steel rims? Razorback? OU? what about OSU? Oh, that's right OSU may not even have a team next year. Maybe with OSU out of the game next year teams like OU and Arkansas can have a chance at a title...NOT!

Find a set of wheels used. They are out there cheap, particularly 27 inchers, but 700c are out there too. I have rehabbed a couple of hundred bikes, upgraded countless wheels, and have yet to have bought a single new wheel. Run a WTB wheels in your local C/L, in the bicycles for sale section.

Saw a set of 700c, with tires, tubes and cassette, on my local C/L yesterday, $40..... I would have bought them, but I was out of town (they are gone now of course).

The only advantage to 700c wheels is that there is a greater choice of tires available , especially in wider widths, such as 700x35 or 38mm . The widest quality 27" tire I've seen recently is 27x11/4.

That's right, and the best 27" x 1 1/4 is the Conti Ultra Gatorskin, Ultra means it's foldable which means it's lighter. But the Gatorskin is $49 tire on sale at Nashbar not including the 10% discount code. Nashbar has quite a selection of 27" tires including 1 1/8 if you want a thinner tire, so if $45 is too much take a look at their others, just don't forget to get the 10% discount code.