erbfarm

I have a circa 1973 Raleigh Grand Prix, I'd like to turn it into a ridable bike if possible. My situation is I live in a very hilly area, to ride anywhere further than 1/2 mile from my house I have to deal w/ serious hills. So I'm thinking really low gears on this bike. Where do I start? The bike didn't come w/ wheels, and the cottered crank has a 52t big ring (I'm thinking too big for my purposes) so that will have to go also. I'd like to put 700c wheels on. Any suggestions for freewheels, cranks, bb? And what other options are there for the centerpull brake? The bike doesn't have any other brazeons or mounts for anything other than fender eyelets above the rear dropouts and on the front fork. I'd really like some feedback. thanks guys!

Maria

roccobike

First, I like early 70s Raleigh Grand Prix's. I have one, but it's too large so I'll have to sell it. OK, you asked three questions, brakes, rims/wheels, and gears.
Brakes, You want to change the center pull brakes, but you didn't say to what. I'm assuming your going to single pivot, side pull brakes. Every time I've asked that same question, the answer from each bike mechanic was the same, there is little to no mechanical advantage to change from center pull to single pivot side pull, I never inquired about dual pivot side pull. However, there is mechanical advantage to change the brake levers from the original levers to aero levers, and they look nicer and make the bike look clean. IMHO, I'd change the levers before I'd change the brakes.
Rims, I'm not a big fan of the original steel, chrome rims. I would buy alloy rims. You might find them on a yard sale bike or a thrift store bike for less than buying on line via ebay. If you buy alloy, check them to see if they have a bead along the inside edge of the rim to help hold higher pressure tires in place. That will make a big difference since you can ride with higher tire pressures. As for 700C, I've made this change twice. In both instances, I had brakes that had a long enough reach to allow for the pads to be adjusted (down) so that they would reach the smaller, 700C rims. While I like 700C over 27 inch, you have to be sure the rims will work with your brakes/bike, or you can purchase longer brakes that allow for the pads to be set properly to stop a 700C rim. The bad news is, I checked the Weinmann brakes on my Grand Prix. The current brakes ARE long reach brakes, and the rear pads are nearly at the bottom of the setting (max extension). I doubt that I can mount a 700C with that set up. The front also had a long reach brake, but it had more adjustment and might work. Your bike may be different or maybe someone else can refer you to an extended reach brake that will work, but make sure your brakes will work with 700C before spending the bucks on those rims. For me, I would stay with 27" rims if I was making these mods on my Grand Prix.
Gears, This is not my best subject. Many 70's bikes sold in the US came with "Alpine gearing". The freewheels had a large rear gear for taking hills. If I were trying to build that bike, I'd start by buying alloy 27 inch rims from another bike and check out the freewheel that came with it. It may have the gearing you want. For what it's worth, my 74 Grand Prix does not have a wide spread between the gears, but I suspect the freewheel is not original.
Once I resolved the rims, then I'd consider other changes like brake levers and freewheels. Should you decide to change the crank, you should check Sheldon Brown's comments about changing the cranks on your bike to new, cotterless, square taper cranks. The good news is, it can be done.
OK, I'll let others disagree with me or add their comments.

erbfarm

Thanks for the info. The Grand Prix didn't come w/ wheels, just the Simplex deraillers, and the Weinman brakes (no levers) so I have no clue what the gearing on the back wheel was. The cranks don't have any name stamped on them, and they've got some rust on them and like I mentioned, I think they've got too many teeth for my hilly terrain so I want to put something different on. As for the centerpull brakes, I'm just wondering what other kind you can use when you only have that one center hole to use for a mount. My other bike has cantis so that's the only kind I'm familiar with. was hoping someone could fill me in on the range of brake options I might have. Oh, and I do have enough room for 700c, the current brake pads are in the middle of the arm, so there is quite a bit of room to move them down.

bikemore 

This thread has a bit about converting from cottered to cotterless BB.

https://www.bikeforums.net/classic-vintage/151785-converting-raleigh-cottered-bottom-bracket-cotterless.html

Charles Wahl

The biggest problem you're going to have with a '70s Grand Prix is the (probable) 26 tpi threading of bottom bracket and steerer tube. Most common is 24 tpi for these assemblies (Italian or English). The second problem is the width of the bottom bracket (probably 71 mm, rather than the more common 68 or 70). If your BB cups are in good shape, that's great. But to put another crankset in (cotterless), you're going to have to find a spindle and crank combination that will a) fit the cups and b) give you a livable chainline. That might be a Mountain Bike (MTB) BB, since those come normally 73 wide. The Raleighs seem to have a weird right BB cup that doesn't have a raised shoulder. I don't know if you can use that to your advantage (screw it in farther), but your should know that you're getting into some very tricky compatibility issues here. If your headset is in good condition, that's another plus. Good news there is that if there's roughness, or parts that have to be replaced, it's usually trouble with the lower bearing, not the upper one, which is limited by the threading issue.

As far as the gearing is concerned, you could a) try to build, or have built, a high tooth-count freewheel; since you don't have wheels, you could actually go to a freehub, and do the same thing -- and then live with the crankset as is. Or, b) go through the complicated exercise of replacing the BB or just spindle, to fit a newer set of cranks. A BB from a later-model Grand Prix might do that -- they came with square drive, though they had studs on the ends of the spindle, not the usual crank bolts threaded into the spindle. If you could do that, then you could, if you were lucky, fit a crankset with 110 BCD (small bolt circle) and use very small chainrings. With 110 you can go down to 34. The expensive option would be to get a Phil Wood BB (they actually still sell stuff that is 26 tpi) -- but I don't think you'd feel that a Grand Prix is worth that sort of investment, unless it was Pa's or Grandpa's bike.

I'm not saying that the Grand Prix isn't a grand bike, or that you can't do what you want to with it; you just have to decide how much frustration and limitation you can tolerate, how much time you want to spend adapting, rather than riding.

Wheelwise, I think that your most cost-effective approach would be to a) buy a pre-made set from one of the online places (they also run eBay auctions for the same thing) or else find a decent lightly-used set with the features you want. Sun CR-18 alloy rims are reasonably priced, for new equipment, or in a pre-built set. There are a zillion hubs out there; freewheel, freehub, old-style loose bearings, cartridge bearings; and on and on.

You will probably have difficulty finding replacement brakes that will have the kind of reach you need to install 700C wheels. The Grand Prix of that era came with Weinmann 610 in front, and 750 in the rear -- allowing max. reach of 61 and 75 mm respectively. You'll need an extra 4 mm reach to go from the original 17" (nominal diameter 630 mm) to 700C (622 mm). I would stick with centerpulls; you're not going to get any better braking out of center-pivot sidepulls. If you really have to "upgrade" the brakes, you will need to measure, and see what reach you need, and buy accordingly. Tektro makes some longer-reach sidepulls (dual pivot?).

You're not going to like this advice, but: if you want to ride the hills on vintage steel, in the long run, you will spend less money, and tear less hair out, by getting rid of the Grand Prix, and buying a ubiquitous Japanese bike (hereabouts known affectionately as a UJB) that has touring cranks on it (a 110 BCD crank, or a triple crankset, which are generally 110 with threaded holes for a 74 BCD "granny" ring). Think Panasonic, Univega, Nishiki. They're much more "standard," and therefore easier to customize to different riding conditions with parts that are readily available.

John E

Charles, are you sure about the 26TPI bottom bracket? If you are correct, perhaps he can force-fit a pair of 25.4TPI Swiss-thread aluminum cups.

For the brakes, I second Roccobike's recommendation: keep those great Weinmann centerpull calipers, but with KoolStop pads, new cables and housings, and aero-style brake handles. Braking leverage will be marginally better with 27" wheels than with 700C.

For gearing, I like the idea of keeping the current crankset with a large tooth count freewheel or freehub. You should not need anything smaller than 14 or 15T for the high gear, and you can easily find up to 32 or even 34 teeth for the low gear. Spread the rear triangle and get yourself a 14-32 7-speed freewheel, for example.

top506

1973 is most likely a Gazelle-made Grand Prix and therefore standard English threading.
If the serial # starts with G you're in.
Top

redneckwes

#5 Spindle, old 26tpi cups, rock and roll.

Early Carlton (Worksop "W") built GP's are 24tpi standard, at least the BB's anyhow.

Kommisar89

Sacrilege!

Sixty Fiver

I'd keep the brakes because they're good... I use a single Weinmann centre pull in my vintage fixed gear and it provides more than enough stopping power.

Alloy wheels will really help for wet braking and lighten the bike as will replacing the cottered axle with a #5 tapered spindle and more modern crank... if the cups are good just keep them.

The wheels may prove to be the priciest item.

Any freewheel with more than 28 teeth will require a long cage derailer.

erbfarm

this is a lot of info to take in! The only serial number I can find on the frame is on the rear drop out, it's 16709 so there's not even a letter in it. It does have a Made in Nottingham plate on the front, and a made in England sticker thing on the bottom (the paint is flaked off in a lot of places). The brakes are the Weinman 610 and 750. Ok, so far you guys have convinced me to keep the brakes(with new pads) and keep the crankset. The headset is still there so I'm keeping that. I guess my only questions are now: what kind of wheels, what kind of hubs, and what kind of freewheel? Aren't the hubs a bit tricky on that bike or don't I have to worry about that? The frame spacing is 120mm so I'm shooting for a 6 compact or straight 6 I guess and I will go w/ the 700c wheels since I know there is room to move the brake pads down on the Weinman's.

Charles Wahl

Hubs are not a problem. With 120 spacing, you can actually fit a 126 mm (6-7 speed) hub in there with no problem, just need to spread the stays as you install the wheel. You could also have a good LBS cold set the frame to 126 width, or even 130 if that's what you decide you need -- but talk about sacrilege! I believe that all the 120 and 126 rear hubs are basically the same (in terms of distance between flanges) -- the difference is just in how thick the axle spacers are installed. Sheldon Brown said that it's the same deal with most all the Shimano freehub models too -- just slice and adjust the spacers to get 126, 130, 135 -- except (of course) Dura Ace. Look at the spacers when buying hubs on eBay or at a used parts place.

If you wanted to stick with 120 spacing, you can get 6 speeds with an Ultra-6, but they're getting rarer. Somewhere I read that all the Suntour "New Winner" freewheels were built on the same mechanism; don't know if that's really true.

You should attempt to check out the threading thing. My bet is that an Nottingham-built Grand Prix will have the 26 tpi disease, but I may be wrong. The serial number you give doesn't have enough characters for a 73-ish Raleigh, and it's not in the usual place, which would be near the top of the seat tube, on the rear of the tube. Should also begin with two letters indicating the manufacture location (N for Nottingham) and the fortnight of manufacture, followed by numbers, first of which is the last digit of year (3 for 1973). Unless it were a 531 tubing model (built at Worksop facility), in which case serial would be on the underside of BB, and begin with a W.

redneckwes

My "W" G.P. is a 20-30 Tru-Wel frame. Worksop built some non, 531 frames too it would seem.

I'm betting the O.P.'s is a Nottingham machine though, but thats no reason to give up.

luker

I had a '73, that I rode for about 13 years. I put a japanese triple bottom bracket in, added a sugino triple crank (from Bike Warehouse, remember them?), and changed the derailleurs out (they failed at about the five year mark) for a shimano triple front and a long-cage rear (maybe a tourney? I remember that I bought 'em used). They worked very well, and I had a 28/28 low gear. Side pulls were very trendy, and supposedly better (naw, not really). I replaced the brakes with weinmann 500's with drop bolts to get the brakes centered over the 700c weinmann concaves that I got used from a racer dude. It was a great setup for the time.

It all went over when I started racing; I sold it and bought a Supercourse Mark II...

erbfarm

I put a japanese triple bottom bracket in,

How did you do that? wasn't there a problem w/ the threading?

mrejda

If anyone knows where to find one of these, I (and the OP of course) would appreciate the info. Harris seems to be out of stock, although I haven't called them.

Charles Wahl

If you do a Google search on the part number used to describe it on Harris' site, you might find another source. Also,, try an eBay search using the "title and description" option (appears below the search criteria when you've made an initial search.

Rabid Koala

Weinmann center pull brakes work quite well....IF you put Kool Stop pads in them. I have them on my P-15 Paramount and they stop very well.

luker

I do not remember that there was a problem. I ordered the parts up and stuck it all together, I'm sure. So mine, at least, was modern standard English threading...

I suppose that I could have reused the stock cups with a different axle, though?

due ruote 

fwiw, I recently worked on a Carlton Grand Prix from about this period. The BB was definitely 26 tpi, as was the headset. Unfortunately.

-holiday76

OK , I'm trying to convert my GRand Prix to cotterless. I'm reading on this thread that you need to use the old cups , and a #5 spindle. But on Sheldon's site I'm seeing this:

""7" series spindles fit "oversized" 73 mm ISO/British bottom brackets, sometimes also work with Raleigh 26 tpi cups in older Nottingham-built Raleigh bikes."

https://www.sheldonbrown.com/harris/bottombrackets.html

So which is it? Is where the heck can I get either one?

mrejda

The #5 should work. As to where to find one, good luck. After a lot of complaining a local C&Ver felt sorry for me and dug one up out of his spare parts bin. He most likely pulled it off of some junk bike he found. I did find this on ebay:https://cgi.ebay.com/VINTAGE-5SS-SCHW...742.m153.l1262
He sent me a picture of the internals and it looked like the spindle might work. YMMV.
edit: measure your BB, it should be 71mm, not 73.

-holiday76

thanks, I'll measure it tonight.