Backtoahobbie

I have a 1978 Raleigh Pro that Im rebuilding for a light around towner for now, my memory of sizing / specs is less than fair.


Looking to build a 6/7 speed, with just a single chainring up front for now.


Components:

Dura Ace 7400 RD and Cranks

Mavic branded hub Campy clincher 126mm.


Just working on the drive train for now, I gotta find a BB and freewheel for now.

SJX426 

Backtoahobbie Welcome! To be able to post pics on the thread, you need 10 posts. But you can upload pics to your albums and then we can post from there for you. Lets see some pics!

Your Raleigh is likely 120 old in the back so putting a 126 in there will be a bit of a challenge. You may want to spread the frame. There are several good sites that provide good directions for spreading the frame. Two important aspects, well three, with the first is to reinforce the brake and chain bridge first, ensure there is equal amount of spread on both sides, and finally, make sure your hanger is parallel to the center of the bike plane. Not spreading the frame is an option but will be tough to insert wheel and you don't know if the spread will be even and the hanger may be off ever so slightly. Oh an watch your chain line with that crank.

I don't know off hand but you may want to find out the max sprocket size for the RD to make sure it will work.

alcjphil

My 1973 Raleigh Pro had 126mm spacing, 6 speed freewheel

Classtime 

Welcome Backtoahobbie
Check this out.....https://www.bikeforums.net/classic-v...ictures-2.html
And there are other threads about "your" bike. There is a search function to show you more (use advanced).

SJX426 

I am now calibrated! Thanks!

Backtoahobbie

120mm. I’m trying to figure a bb an spindle length. Appreciate the cycle sass

alcjphil

Are you thinking about bottom bracket spindle length or rear triangle spacing? The raleigh pro was an early example of 126 mm dropout spacing, nothing to do with bb spindle length which depended on the crankset being used

Backtoahobbie

bb spindle length, 112, 110?

Backtoahobbie

Posting Pictures Soon

SJX426 

Good! I would like to see a 126mm Rim!

repechage

First name the crank. Mfg, model, and sometimes year all can make a difference.

Baypathbike

My 1978 Mk V has 126mm spacing

TiHabanero

The 1979 model I have since new is 126mm axle spacing. The 1973 my brother has is 126 axle spacing. As for BB spindle, will need to spec according to Shimano 7400 crank recommendation. Did not look it up, but I believe it is 113mm. Anything over 112 will work.

Joedead

Hello everyone,

It looks like rear spacing spec for my 1978 Professional is 126 and confirmed by some of these posts. I currently have 126 mm Origin 8 hub with a six speed freewheel and friction shifters, this worked great (not past tense). My apologies in advance for admitting that I did not restore this bike to its original glory using vintage parts.

Last week my friction shifter failed. I am considering two options:
1. simply replace the friction shifter with a new or used downtube friction shifter. This will obviously work and would be an simple fix.

2. Upgrade the freewheel to a Sunrace 7 speed MFR30 7CQ 13 -25 and Sunrace 7 speed downtube index shifter SLR 30. My question is will the freewheel fit and function on the rim and work on the bike without spacers and re-dishing the rear wheel? In other words will this set up not work and turn into a headache?

Thank you as always for your advice and input.

Cheers, Joe

Pars 

The '73 Pros and on were 126 and 6 speed. Same with the '73 RRA. The Internationals, etc. were still 120mm (5 speed). You can see in the attached '73 price list.