Spa Steel Touring frame

[pete75]

These are looking even better value. Spa are doing the frame at £315 and complete bike at£945 during Dec & Jan for CTC members.

[2wheeler]

Ok the computer is telling me the stack would be 555mm but the reach would be 383mm.

Thankyou for those figures.. I had a look over my calculations and get the reach to be 384mm, so that agrees with your cad derived 383mm

While we're about it, would you be so kind as to nip down and take a couple extra measurements for me please . They relate to clearances between tyre and cross members on the rear seatstays, top and bottom, and to front fork clearances.


So for the 51cm frame, I'm after 3 measurements...

a) distance between front fork dropout centers and underside of fork crown.

b) distance between rear dropout centers and the nearside of the bottom seatstay crossmember

c) distance between rear dropout centers and the nearside of the top seatstay crossmember


in other words b) and c) are the radius to the insides of the top and bottom crossmembers


Cheers, Gordon

[MikeF]

Mike F....
Can you give us some measurements of your existing bike......
BB axle to top of seat tube
top tube (centre of seat tube to centre of head tube)
Front wheel spindle to top of head tube
stem length.
front centres (bb axle to front wheel spindle)

This will allow fairly accurate comparisons.
Spas 48cm tourer has 26" wheels, I don't think 700 wheels are an insurmountable problem on a 51cm frame

Colin I've been away so not had a chance to measure until now. Measurements in centimetres.

Bike 1 straight handlebars, 26" 559 wheels, diamond frame
BB spindle - ST top 49.0
TT (ST- HT centre- centre) 54.5
Stem length Horizontal 9.0 Actual 11.0 (it's a rising stem)
Front wheel axle - top HT 50.0
BB - Front wheel axle 62.5

Bike 2 old type drop handlebars, 700c 622 wheels, diamond frame, non aero brake levers, down tube shifters
BB spindle - ST top 54.5
TT (ST- HT centre- centre) 54.0
Stem length 7.5
Front wheel axle - top HT 50.5
BB - Front wheel axle 61.0

Bike 1 seems to have quite a relaxed seat tube angle compared with nearly all modern bikes with that size frame.
It's just occurred to me that as it has a diamond frame it could easily be calculated using a ruler, plumb bob and trig.
Bike 2 is marginally too big in reach although I have ridden it for years, but it's interesting to note that the figures for both bikes are very similar.

I am not looking for 26" wheels specifically and I'm reasonably certain Spa's 51cm will be fine, but I would be very interested in your comments. Spa has also reduced the price for December and January.

What advantage or disadvantage does 853 tubing have over 725 apart from being more expensive?
Mike

[MikeF]

Mike, I'm the same height as you, a tad under 5'6". I normally have the saddle at about 66cm high, which was by chance exactly how their test bike was set up.

How are you measuring this? Is it vertical height to BB centre, or along the seat tube to BB centre?

[531colin]

Just so you know, I designed the Spa bike.
Theres loads here http://forum.ctc.org.uk/viewtopic.php?f=5&t=81415&start=15 about tyre clearance on the Spa bike.
It will take Marathon 700x35 tyres with mudguard clearance. This is about the maximum tyre you can use with mini vee brakes and guards, and rightly or wrongly most customers choose drop bars, road STIs and mini vee brakes.

My head is reeling with all these numbers!
To be honest, now you have reach and stack, which as you say you can compare with your existing bikes with a plumb line and level, I don't think its helpful to look at a whole different lot of measurements. You need to know seat tube angle fairly accurately to compare (effective) top tube lengths, one degree error in estimation can give a 10mm or so error in reach. But if you want to play, I think all the numbers you need are on Spas website.......front spindle to head tube top is fork length + head tube length + about 12mm for the bottom headset race.

I'm riding to-day, so this is just a quick response, I will re-visit probably this afternoon.

BTW, who is the librarian?

[pete75]

Just so you know, I designed the Spa bike.
Theres loads here http://forum.ctc.org.uk/viewtopic.php?f=5&t=81415&start=15 about tyre clearance on the Spa bike.
It will take Marathon 700x35 tyres with mudguard clearance. This is about the maximum tyre you can use with mini vee brakes and guards, and rightly or wrongly most customers choose drop bars, road STIs and mini vee brakes.

My head is reeling with all these numbers!
To be honest, now you have reach and stack, which as you say you can compare with your existing bikes with a plumb line and level, I don't think its helpful to look at a whole different lot of measurements. You need to know seat tube angle fairly accurately to compare (effective) top tube lengths, one degree error in estimation can give a 10mm or so error in reach. But if you want to play, I think all the numbers you need are on Spas website.......front spindle to head tube top is fork length + head tube length + about 12mm for the bottom headset race.

I'm riding to-day, so this is just a quick response, I will re-visit probably this afternoon.

BTW, who is the librarian?

Maybe a test ride might be better than asking for loads of measurements. Even if they are all spot on the "feel" of the bike may not suit a particular individual.

[Jezrant]

Mike, I'm the same height as you, a tad under 5'6". I normally have the saddle at about 66cm high, which was by chance exactly how their test bike was set up.

How are you measuring this? Is it vertical height to BB centre, or along the seat tube to BB centre?

Hi Mike, that's my saddle height as it's normally measured, i.e. from the centre of the bottom bracket to the top of the saddle (going up the middle of the seat tube). What's your saddle height?

BTW, any particular reason why you prefer 26"? There's a larger choice of road tyres in 700c than 26".

Edit: just saw the bit about 26"/700c in your last post.

[iviehoff]

Does anyone know who makes Spa's frames these days?

Frames are made in the Far East. Wheels are built and all assembly is done in the shop in Harrogate. Warranty is by Spa.
Because English framebuilders expect to be able to feed a family, the 853 frames made by Lee Cooper were comparable in price with a far eastern Ti frame.
I'm sure any English framebuilder would build you a frame, if that's what you want.....Lee has the drawings....

I was just interested to know whether he could still do it economically be employing English framebuilders as he (or at least his father, who was the one I knew) did in the past.

[pete75]

Does anyone know who makes Spa's frames these days?

Frames are made in the Far East. Wheels are built and all assembly is done in the shop in Harrogate. Warranty is by Spa.
Because English framebuilders expect to be able to feed a family, the 853 frames made by Lee Cooper were comparable in price with a far eastern Ti frame.
I'm sure any English framebuilder would build you a frame, if that's what you want.....Lee has the drawings....

I was just interested to know whether he could still do it economically be employing English framebuilders as he (or at least his father, who was the one I knew) did in the past.

Probably be about 200 quid more made here eg Bob Jackson World Tour frame is £550

[531colin]

Realised I can answer a few questions from the drawings.....
axle to chainstay bridge is 375 (centres) so subtract half of 16mm diameter bridge gives 367 clearance.
axle to seatstay (brake) bridge is 375 centres, but I don't have the bridge diameter....the stays are 16mm diameter, so it won't be more than that, ie. clearance comparable with the chainstay bridge.
at the front, axle to crown race seat is 385, fork crown is about 18mm deep from memory, gives 367 clearance again.

Its readily possible to get much too hung up on "what tubing is it?"
its 725 main 3 tubes, stays and head tube are plain gauge cromo, forks (from memory) are butted cromo.
Now the fun starts....
apart from the steering geometry, the main determinant of how the frame rides is the stiffness of the frame, and the main determinant of frame stiffness is tube diameter....stiffness varies with the cube of the diameter. Stiffness varies also with the length of a (single, straight) tube. Now I forget the numbers, but its maybe something like if you make the tube 20% longer, then its 30% less stiff. It follows that small, light riders are usually riding a frame that's much stiffer and less comfortable than ideal, and big tall strong riders are often riding a frame that is too flexible.
I have had a stab at equalising all this out by using bigger top and down tubes on the bigger bikes, but I think I'm right in saying that most manufacturers don't bother.
its difficult with a production frame, there are lots of people shorter and heavier than me, and a few taller and lighter....its a case of take your best guess and build a prototype.

what was the question?....oh yes, 853...its strong and it welds well, so you can make the walls a bit thinner and shave a bit of weight, and its a nice springy ride if you get the tube sizes right....on a camping tour, it will make very little difference....

[bigjim]

I sometimes wonder why we make our choice of bike so that it will suit a 2 week loaded holiday once or twice a year? Unless you have only one bike, it will then sit in the shed or whatever for the rest of the year.
If you do have only one bike, then is it not better to make decision on a lighter more useful road bike and then gear this up for the odd time you will use it on tour?
I'm just as guilty having bikes for different roles, but any of them would probably be up to any job with a possible change tyres/wheels etc.
Although I must admit I don't pay that much for my bikes.

[Jezrant]

Realised I can answer a few questions from the drawings.....
axle to chainstay bridge is 375 (centres) so subtract half of 16mm diameter bridge gives 367 clearance.
axle to seatstay (brake) bridge is 375 centres, but I don't have the bridge diameter....the stays are 16mm diameter, so it won't be more than that, ie. clearance comparable with the chainstay bridge.
at the front, axle to crown race seat is 385, fork crown is about 18mm deep from memory, gives 367 clearance again.

Its readily possible to get much too hung up on "what tubing is it?"
its 725 main 3 tubes, stays and head tube are plain gauge cromo, forks (from memory) are butted cromo.
Now the fun starts....
apart from the steering geometry, the main determinant of how the frame rides is the stiffness of the frame, and the main determinant of frame stiffness is tube diameter....stiffness varies with the cube of the diameter. Stiffness varies also with the length of a (single, straight) tube. Now I forget the numbers, but its maybe something like if you make the tube 20% longer, then its 30% less stiff. It follows that small, light riders are usually riding a frame that's much stiffer and less comfortable than ideal, and big tall strong riders are often riding a frame that is too flexible.
I have had a stab at equalising all this out by using bigger top and down tubes on the bigger bikes, but I think I'm right in saying that most manufacturers don't bother.
its difficult with a production frame, there are lots of people shorter and heavier than me, and a few taller and lighter....its a case of take your best guess and build a prototype.

what was the question?....oh yes, 853...its strong and it welds well, so you can make the walls a bit thinner and shave a bit of weight, and its a nice springy ride if you get the tube sizes right....on a camping tour, it will make very little difference....

That's all very interesting. You've really put a lot of thought into these frames. I honestly think the steel frames are by far the best steel touring frames available in the UK in their price range. Now, I hope this doesn't sound too hung up, but I was wondering about the tubing diameters and gauges of the three main tubes. Do you remember what they are for the 51cm frame?
Cheers

[RJS]

Ooook, what's with the spear You don't usualy get those in a library, even in Unseen University. Sorry, this should probably be in Tea Shop, or rather, Banana Shop.
The Librarian

[Brucey]

....apart from the steering geometry, the main determinant of how the frame rides is the stiffness of the frame, and the main determinant of frame stiffness is tube diameter....stiffness varies with the cube of the diameter. Stiffness varies also with the length of a (single, straight) tube. Now I forget the numbers, but its maybe something like if you make the tube 20% longer, then its 30% less stiff. It follows that small, light riders are usually riding a frame that's much stiffer and less comfortable than ideal, and big tall strong riders are often riding a frame that is too flexible.
I have had a stab at equalising all this out by using bigger top and down tubes on the bigger bikes, but I think I'm right in saying that most manufacturers don't bother. ....

Tube torsion and bending stiffness goes as the cube of the diameter (OD) if the ID stays the same (which of course it won't).

At constant wall thickness the stiffness goes as the square of the diameter.

At constant weight ( so wall thickness less pro-rata in larger diameter tubes) then stiffness goes with diameter.

Longer tubes +20% in a simple cantilever bend will deflect approximately +70% more at the free end (for a given end load). This loading etc isn't like that seen in a real bike, but the takeaway is that longer tubes (of any given diameter and gauge) are disproportionately more flexy; this is made worse again in most cases because the applied loads into larger frames by larger riders are also likely to be... larger...

cheers

[531colin]

what is it with the librarian?....I still don't get it......maybe its a generational thing?