Tyre knowledge (vintage) required clincher but not !!!??? Help!

[Mickeyspinn]

I've nearly finished recommissioning a rather special and lovely old bike that belonged to my french gramps,it has what I'm pretty sure are either the first or very early Mavic rims but pre clincher as we know it ! They're not tub rims definitely clincher style.... simply put they have no lip for the tyre bead to "catch" in the profile!

I've tried quite a few 700c tyres one of which would maybe go on with lots of chalk.....however when your losing skin,plastic tyre levers turn to jelly and begin to cry yet there's still 8" of sidewall to go you know it's not right! I don't want roadside puncture repairs taking an afternoon!
So...anyone know of a 700c around say 30 to 35 wide that might fit? Don't have to be retro but do want something light, cotton tan/gum sidewalls would be sweet.
I've a feeling that tyre pressure is going to be critical on these rims.
Any and all help gratefully received .....once it's tyred I'll just need to source some correct calipers and it's rideable and ride it I will!

 

[jim haseltine]

Rims never used to have hooks, they came in during the late 1970s along with the first folding light weight tyres. Don't assume that the rims are for 700c tyres, we used to sell a lot of French bikes (Peugeots, Motobecanes etc.) that were fitted with 27" wheels for the UK market.

 

[Mickeyspinn]

Rims never used to have hooks, they came in during the late 1970s along with the first folding light weight tyres. Don't assume that the rims are for 700c tyres, we used to sell a lot of French bikes (Peugeots, Motobecanes etc.) that were fitted with 27" wheels for the UK market.

The rotten tyres that came off were 700c,if I'm correct in thinking technically you could put a 27" tyre on/over a 700c rim although they'd never "seat" but not a 700c tyre onto a 27" rim? There's absolutely no sizing or manufacturer brand markings on the rims but they do look very similar in profile to first Mavic alloy rims,not identical tho as there is an ever so slight ridge on the outer profile whereas the mavics I've seen do seem to be more of smooth profile....the weld and how they were filed into shape looks so similar tho. They are possibly very early... the bike was bought in 1943 Think I'd better wheel it in and snap some pics... maybe a positive id on the rim will help!
Cheers!

 

[Mickeyspinn]

outer width is 25mm and internal is 16mm. depth from rim edge to internal shoulder is about 6.3mm this measurement seems fair bit deeper than any other 700 rims I have!
Anyone have any ideas what rims these are?

 

[pigman]

I'd measure the diameter and compare to some modern 700Cs just to be sure and tick that one off.

I assume you know, but just in case, don't forget to ensure that the spoke ends don't show proud of the nipples and fit the protective rubber band over the centre ridge

 

[Mickeyspinn]

Yes I've just done that measures up the same diameter wise I'll be reusing the original Hessian and cotton padded rim tape ! Trying to keep it all as found .

 

[jim haseltine]

if I'm correct in thinking technically you could put a 27" tyre on/over a 700c rim although they'd never "seat" but not a 700c tyre onto a 27" rim?

Correct.
I think I can see your problem - that's a really shallow rim so the only way you'll get a modern tyre one is to ensure that the beads on the opposite side of the wheel are pushed as far as possible into the rim well (not that there's much of one). Even then it'll be a struggle. We had a tool that was supposed to be for fitting solid tyres which I would use whenever we were faced with a really tight tyre/rim combination - had to take care though as it was easy to put enough force in to damage things.

 

[Mickeyspinn]

Agreed! It's shallow yet the shoulder for the bead is deeper by about a 1.5mm !
So tight going on but baggy when in.
Definitely going to have inflate slowly whilst helping the tyre to seat true
Certainly want nice new supple sticky beaded tyres I don't want to roll the bead out whilst cornering
If I could get a positive id on the rims I might be able to find someone whose found a good fitting tyre. Can't really afford to keep buying tyres in the hope I get lucky.

 

[Mickeyspinn]

When removing the old tyres which were Hutchinsons they were so tight the spokes creaked!

 

[non-fixie]

Cover the beads as well as the inner tube with liberal amounts of talcum powder. Especially with new tyres, this will help the tyre slide into the well and over the rim.

Oh, and don't use folding tyres on hookless rims. Chances of them staying on under pressure are pretty slim.