Tubular Tyre Replacement (Tubs)

[whitesix]

Hello I have a Knights Cycle, see images attached. I believe the bike was made around 1982, some 38 years ago. I purchased the bike from the father in law of a good friend some 33 years ago and the tyres are the same as when I purchased it. I think they therefore need renewing. Can anyone help me with this please. I understand the tyres are know as Tubs and from the image they have a yellow patch stating Liontyres GT 30 (or50 or 80); there is also a badge on the wheel rim stating Super Competition Champion Made in France. I'm really not sure where to start and the wheel rim measures around 24" dia (ie side to side); what size therefore are the wheels?

I have consulted a very well respected bicycle mechanic, but he does not go back this far and has no experience with this sort of tyre. Can anyone also recommend a good video or any instructions to enable me to fit such a tyre, when I can establish which tyre I need to purchase and where such tyres can indeed be purchased from.

I am also considering if it would be viable to have the wheels re-built, because some of the spokes are a little rusty?

Any help and assistance would be very much appreciated. I have also posted this within the vintage section, but perhaps it should have been posted in here, Mechanics and Repairs; apologies for any unnecessary duplications.

 

[Cycleops]

Those will be 700c wheels. Tubs need gluing to the rim which has a shallow U section. If the spokes are rusty I should remove them and have them built up with conventional clincher rims. Availability of tubs is poor these days and are generally quite expensive plus they have poor puncture resistance and mending them is a pain. If you insist on using them Vittoria have the cheapest (£60pr): https://www.evanscycles.com/brand/vittoria/rally-tubular-tyre-976399
Back in the day they were used mainly for competition.
That's a very nice bike and looks in excellent condition with a quality 531 frame so well worth upgrading the wheels.

 

[Ajax Bay]

https://www.sjscycles.co.uk/tyres-t...no-t-hs424-tubular-tyre-black-700-x-22-22622/
Something odd with the two teeth on the large chainring 'behind' the right hand crank?

 

[Sharky]

I rode tubs for many years and they are nice to ride. If you get a puncture, you just rip it off the wheel and put a new one on and off you go. Can be done in about 4 minutes.

But that's where the plus points end. You always need to carry a minimum of one spare tub and on a long ride, probably two. When they were popular, club mates would be carrying spares, so they would help you out.

They can be repaired and I have done it at the road side, but you need to carry razor blades, needle and thread and a thimble as well as normal patches.

I converted to clinchers in the 90's and wouldn't go back now and would recommend the same.

 

[whitesix]

Hello Sharky, my tubs seem to be well stuck on; I don't think they could be ripped off and replaced, but perhaps with a new set and a re-glue that would be possible. That does seem like a lot of kit that you need to carry about with you and obviously I do not have the experience as to why you would need razor blades and needle and cotton etc. Cycleops has also suggested the new wheel route; I am assuming that a new wheel rim and spokes would have to be produced utilising the original wheel hubs to maintain authenticity; would you have any idea of how much the parts and works are likely to cost?
I have a MTB that I am currently using and my main aim is to ride for fitness and therefore I am wondering if perhaps it may be prudent to consider to perhaps think of purchasing a new road bike (depending on the cost of the wheel renovation)?
Sorry, so many questions; depending on answers to the suggestions above is there a market for my Knight bike or is it really merely for the real enthusiasts as a labour of love?

 

[Sharky]

Tubs are sewn together and taped over. An old fashioned razor blade is small and fits in the tool bag easily. You need this to cut the stitching in the area where the puncture is. Finding the Puncture hole is an art in itself and if you start cutting the thread in the wrong place, you end up with a lot of re stitching. Once you pull the inner tube out and patch it and push it back in, the next step is to stitch it all back up. This is where the waxed thread,, needle and thimble come in. Imagine trying to sew heavy canvas. You need the thimble to push the needle through.
Removing a tub is just brute force, once you can get a start. Solvents might help, but I just used force.

No idea on costs for rebuilding. There are some experts on here who will know. If your hubs are in good condition, probably worth a rebuild, especially as the rear hub won't be the same as modern 130mm hubs. Find a wheel builder and discuss options.

Good luck.

 

[whitesix]

Thanks Sharky; learnt something new; I thought Tubs didn't have an inner tube; probably like most things, obvious once you know it. Yes, I can imagine, not really something you want to be doing at the side of the road! I suppose that you have to be extremely careful that you don't pierce the innertube, when you are re-sewing up the tyre as well (if of course I have understood the process properly).

 

[screenman]

https://www.sjscycles.co.uk/tyres-t...no-t-hs424-tubular-tyre-black-700-x-22-22622/
Something odd with the two teeth on the large chainring 'behind' the right hand crank?

Looks like a shadow to me making the two you see the actual ring.

 

[whitesix]

Thanks Dogtrousers; so I'm looking at probably around £260.00 for two wheels, new tyres and innertubes etc and I'm still going to be riding with the old style gear shifters on the down tube (and not the new fangled shifters, linked in with the brake levers, as they now are, as I understand it).

 

[whitesix]

Ajax Bay, I can see what you are saying now, as screenman says, yes, it is a shadow, the large chain ring is fine; no damage, no teeth missing!

 

[Ajax Bay]

Though you haven't stated your aim here, you've implied it - wheels that complement your lovely bike. I was going to offer you a spare tubular but I'd agree with others, rebuilding with new spokes and clincher rims is the way to go.
But first I'd give those lovely hubs a good service to make sure they're in sufficiently good nick to use. I assume they are both 32 spoke wheels/hubs.
Then (for style) select a box section 'silver' rim - Mavic Open Pro has been mentioned but the Mavic Open Elite is cheaper and entirely fit for purpose.
For spokes choose Sapim Race or DT Swiss Competition, doubled butted, and silver of course, with brass nipples.
@Dogtrousers has given you some likely costs (less with a £28 rim) so say £65 per wheel (with your hubs). Tyres (622-25) are anything between £15 and £35, plus £5 for a tube and £1 for rim tape (LBS will do that). And you're done and riding, confident that if/when you puncture you can be up and riding 10 minutes later.
https://www.cyclechat.net/threads/knight-frame-me-likey.197502/

 

[biggs682]

@whitesix swapping over to clincher wheels makes a lot of sense as others have said.

There's enough choice out there new , but nothing wrong with picking up a set of second hand wheels or another bike of same era and just using the wheels .

You might be surprised how little you would pay going second hand route.

Have a chat with your tame bike mechanic and see what he says .

 

[Sharky]

Assuming you have a screw on freewheel, a wheel like this won't hurt the bank balance

https://www.sjscycles.co.uk/wheelsw...-wheel-with-screw-on-freewheel-all-black-36h/

And you can probably find a similar priced front wheel.

But this wheel is 130mm oln, which could make it tight getting it into the frame.

 

[whitesix]

Thanks Ajax Bay, very kind thought, but, I think that all of the excellent advice I have received within this post lends itself to a wheel rebuild.

 

[SkipdiverJohn]

There's enough choice out there new , but nothing wrong with picking up a set of second hand wheels or another bike of same era and just using the wheels .

You might be surprised how little you would pay going second hand route.

This is the route I would go. It always amazes me on here that people will tell you a new this costs X, and a new that costs Y, then you've got to pay the LBS mechanic Z to put it all together. No you haven't. There's plenty of used stuff around, available at prices from free upwards.
Road racing/club sports/touring frames historically were almost always made in one of two wheel sizes, either British 27" with a nominal diameter of 630 mm, or Continental 700c sizes with a nominal diameter of 622 mm. Today, the 700c size has largely replaced the 27", but the size difference is small. 700c size wheels are absolutely everywhere in the cycling world, and the wheel has a radius just 4 mm less. That means so long as your brake calipers have even just a tiny amount of available adjustment left in the slots where the brake blocks are mounted, then 700c wheels can be used instead of 27".
Replacing a 700c tubular tyre rim for a 700c wire bead clincher tyre rim is even easier, it's a straight swap. The only thing that matters here is the rim width needs to be within the limits of what will clear the frame when mounted on the bike with an inflated tyre.

Edited to say the easiest option of all would just be to ride a modern road bike instead, but then you'd miss out on that tangible but very difficult to describe in words quality that a good hand-built Reynolds 531 frame has. If you've ever ridden a frame like that, you'll know what I'm going on about. I have a nice little collection of old 531 bikes, and they are nothing like riding modern stiff alloy framed bikes. Much more comfortable.