I would like to turn my first bike, a 1972ish Moto Grand Record, into a 1 x (10?). Right now it's a beater, so I stripped it down and want it to be something I will actually enjoy using, probably including a powder coat new look and hand-paint the lugs. The rear dropouts measure at 120. I know a modern wheel with cassette needs 130. I've watched RJ Bike guy's videos about cold setting. I'm guessing the real risk is the brazed brake bridge and chainstay bridge? As well as general alignment? Any additional warnings/advice about trying this? Thanks.

The bridges won't break unless they were either badly brazed in the first place or developed cracks during use. If it breaks, in my opinion that means you already had problems. The high-end Motos from that era that I have seen are pretty well-built, displaying none of the quality control issues prevalent on their British contemporaries.

It is pretty easy to align a frame with string and a ruler. Having calipers and a large adjustable wrench to align the dropouts and a properly dished wheel to put in and check things also helps.

A Grand Record, as far as I know, should be all Reynolds 531, so it will be harder to spread the rear triangle than the lower-end "hi-tensile" frames, but won't offer nearly as much resistance as more modern bikes would. You can do it incrementally with a threaded rod between the dropouts, but I prefer putting 2x4s or other lumber between the seat tube and the dropout and prying them apart with my arms. This allows you to more easily make adjustments independently on either side, especially if you can fix the bottom bracket in a vise or clamped to a bench. Plus the lumber is easier to remove in order to insert a wheel or whatnot.

I think you are correct about all 531 tubing (decals all gone but catalogs that I've found online show either 531 main tubes or all 531). No visible cracks or defects. Thanks.

Most people recommend building a clamp to hold the brake bridge while you're doing your adjustments.

A '72 is Reynolds 531 main frame (not the fork and rear triangle). By '73 the fork was Reynolds but not the rear triangle.

531 main tubes if a '72; main tubes and fork by '73. Who knows what the rear triangle was made of but it wouldn't surprise me if it were hi tensile steel.

By the way, you can fit a pretty fat tire if running 700c. I'm running 700 x 35c Schwalbe Mondial tires on my '73 Motobecane Grand Record.

Thanks, and honestly I'm not sure the exact year. The components based on the catalogs place it somewhere in there. But I'll assume the rear is not anyway. I bought it around '74 from the original owner.

That's good to know. What brakes are you using? My Mafac Racers are definitely serviceable and figured I would stick with them.

The Mafacs are fine brakes. Kool stop makes pads for mafac racers. My Moto came with Weinmanns and they work great especially with kool stop pads. The bike has an impressive amount of clearance for a fat tire. I'm running a "compact" crank (really a Nervar 631/633) with 50/34 rings and a 5 speed 14-28 freewheel.

I've cold set 4 frames, all Columbus tubing. I haven't broken a bridge yet. I tried the threaded rod method on a TSX frame . Every time I spread it with the rod, the frame just went back to 126 mm when the rod was removed. I probably got it up to 145 mm with the rod and left it for a day, It just went back to 126 mm. I use the 2 x 4 method, but slightly different than what is seen on the web. I lay the frame on a blanket, put the 2 x 4 under the top drop out and against the bottom chain stay as close the the bridge as it can go ( if you cut the end of the 2 x4 at an angle, you can get it right up against the bridge). I hold the bottom drop out down with my foot and lift the 2 x 4. It doesn't take much to cold set. I then flip the frame and do the other side. I constantly check alignment with the string method and work both sides gradually. Then I check the dropout alignment and derailleur hanger alignment.

I do it with lumber and a chair, and a set of calipers. it's the best way to be sure you are moving the dropouts equally; threaded rod doesn't at all.
If it's 120 and has to be 130, bend one side until it's 125, then bend the other to 130. Sorted - and straight.

I used a clamp on my first one. It fell off halfway through spreading it! Gave me quite a shock, but the frame held strong.

Since then, I think I've done 20 or so frames, none with clamps. There may be certain use-cases for a clamp, but I have never used one since my first.

I cold set my 72 Moto Grand Record with the 2x4 method and no clamp, and it went fine. I spread it to 128mm so I could use a 126mm wheel and move to a 130mm wheel later if I wanted to. Little moves, check it constantly...

Mine has the last remnant of a decal with a "3" on it, so it is definitely Reynolds main tubes only, not chainstays or seatstays.

The clamp is absolutely necessary, in my opinion. The second concern is over bend and needing to bend back. Care and careful measuring after each bend attempt will help to guard against this. Finally, equal bends on both sides are important to keep things running true to the centerline of the bicycle. Once drop to drop distance is achieved, you must align the drops, ensuring that they are bang on parallel to one another. Fingers crossed is a rarely mentioned part of this procedure.

I never use a 2 x 4. They are too unwieldy. making it more difficult to modulate the force being applied. My ideal cold setting tool is the shaft from a broken, wooden, hockey stick. Pre-Covid there was a ready supply for free, in the garbage bins outside ice rinks.

...but this is more or less how I do it. I don't worry too much about the bridges, but I don't usually make adjustments that go to 10 either.

I guess I can see some valid reasons for going to 126, if for no other reason than the freewheels are easier to find. But unless I had some set of 130mm hubbed wheels lying around, and I was desperate to use them, the switch from 5 cogs in the back to ten has little to offer in the way of improved gear range and some definite disadvantages if your ten speed chain has some trouble on your old chainwheels, because they're cut a little wider at the tooth, and are spaced far enough apart for that chain to drop down in between them some time when it is inconvenient.

And I find it problematic friction shifting a ten cog rear, quickly and by feel. I'm sure there are people who do it, just not me.

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...I see your intention is a 1X10. My apologies for missing that. I have zero experience with those. Anyway, I hope the pictures give you some idea what's involved.

fwiw, I have cold set once, from 126 to 135 on a 82 nishki. I used the sheldon brown 2x4 method.... bit scary but work out well. https://www.sheldonbrown.com/frame-spacing.html

Just thought a thread on frame alignment should include a picture of professional tools. I didn't have dropout alignment tools (Campy H tools) in this picture but 3Alarmer has those covered. I'm not a proponent of the string method because it assumes the front triangle is correctly aligned. More often than not it is not. I've aligned thousands of frames over my long career and especially classic era frames are out. Many of the best Japanese ones are spot on. The Park Frame Alignment Gauge is not that expensive and a much better option than using string.


In this picture you will see a surface gauge with a bent point to check that the tubes are parallel to the cast iron surface. There is also a black V step gauge that lets me know the dropouts are equidistant from the frame's centerline. The unit is adjusted up and down by placing the V into the seat tube. The the inside of the dropouts should match one set of steps. The Park tool is there as well as 2 of my own versions. Mine could be used instead of the table by placing it against the face of the BB shell and adjusting the end of the screw to just touch the tube near the BB and then again out on the other end to see if it matches. If not, bending begins.

If the rear triangle is hi tensile steel on your '72 Motobecane Grand Record, you should be able to spread that rear triangle by hand. I did that on a 70s Peugeot PR 10 (531 main frame, hi tensile steel rear triangle and fork).

For a little perspective, a couple years ago I cold set a decent quality Ross frame (Ishiwata tubing?) for my wife’s use as a city bike, by laying on the floor and levering with a shovel handle. She’s very happy with it.

Your bike is gorgeous. Mine is almost down to bare metal after years of neglect so I'm not restoring it, but repurposing.

OOps, newbie here. That was meant for Bikemig's black & red pic.

Yeah, I started out thinking a single speed, but my terrain and riding style, age and fitness wouldn't get much use out of that. So I focused on the 1 x 10 with tubeless wider tires, which I think I will use a lot and I'm not interested in a bike hanging on the wall. Thanks for your feedback, all great info.

I'm not 100% certain on the original year. I bought it around 74 from a guy who raced a year or two (don't remember). I know the original equipment (still have most of it) and that puts it in around that year. (FWIW: Campy Nuovo Record der/levers; Mafac racer brakes; Normandy Competition Luxe hubs/Weinman rims; Pivo stem; Brooks pro saddle (lost in a move, damn!); Stronglight bb/crank/headset. Atom pedals). I'm not clear on the steel differences: if it happens to be 531 rear will it not take kindly to cold setting?