Stuart Sinclair "Cadburys" 731OS

[juice.bikes]

Been a while since I've been thinking about bikes let alone riding them since I lost my workshop last year but somehow I've managed to end up with one more..

Was watching this bike on ebay for a few weeks and was genuinely surprised that I wasn't outbid when I took a very very last second punt at auction.. I bought it to build up and sell on as it was labelled 23" but after the ride home from Euston station I was very impressed by how stiff and fast it felt! I've had a couple of 731os frames through my workshop, one was a Mercian 700c time trial frame I built up as a cruiser for riding around LA back in 2019 and it felt great to ride albeit a bit small/low.



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Stuart felt a bit small for what I thought was a 58cm frame - I don't really use inches - so was pleasantly surprised that top tube measured 56.5cm ctc and seat tube 56cm ctc. Only a cm bigger than my 531c Brian Rourke which is my summer run around. I slept on it for a week and thought that if I can fit some bigger tyres, the "23mm" horrible green tyres on there atm made me feel sick, then I'll fix it up to potentially keep it.

I dug out some GP5000s from the stash and told myself theres no way these will fit in the already tight front brake bridge clearance but by some stroke of luck the front tucked in with about 1mm to spare.. def channeled my inner track/fixie/hhsb! Re done the cables, tape and switched out the stem/bars to something a bit more aesthetically pleasing.. can't really stand the 3ttt Pro Chrome stems, especially on a smooth fillet brazed frame like this. A quick service and I was off riding it to work and back with only praises to mention! Felt great overall and the power transfer was a big step up compared to the Rourke but wasn't fully convinced it would work out size wise.

Anyways, took some photos today and here it is as it currently sits -

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Plan is loose and very much tbc but for now I think an emphasis on upgraded to lightweight equivalents, 9 Speed DA for example. I want to sell the wheels as I can't get with the red tbh. I have a set of Hope TI Glides I want to use on something and this seems like the best bet but need to decide on rims, something shallow and silver or anodised grey. A slightly longer titanium? stem and modern compact bars like Nitto M106 - the shape on the 3tt's don't really work for me aesthetically Titanium seatpost maybe? or a Ultegra 6600 smooth finish post? shaved 50 grams putting on this Nitto S65 compared to the 600 it came with so could be easy to loose some weight here...

Anyways, any input welcome. Oh an if anyone has any history or info on Stuart Sinclair please send in

 

[sjcprojects]

That is a beautiful frame. Thank god you lost the green tyres ASAP . And I certainly agree about the wheels – those might work on some bikes, but not this one. Silver or grey will be a big improvement.

I've not heard of Stuart Sinclair, so it's always nice to see something new. Presumably a builder fairly local to Corby?

 

[MartinB123]

Gorgeous

Colourway reminds me of my MB Dronfield lopro. Like what you've done so far.

 

[peetee]

I have a 731 frame by Rixon. I’ve owned just about every iteration of Reynolds steel tubing and 731 is the best, IMHO.

 

[juice.bikes]

That is a beautiful frame. Thank god you lost the green tyres ASAP . And I certainly agree about the wheels – those might work on some bikes, but not this one. Silver or grey will be a big improvement.

I've not heard of Stuart Sinclair, so it's always nice to see something new. Presumably a builder fairly local to Corby?

The only bits of info are that he built frames when he was working for Bob Mitchell Cycles, around 100 frames. Someone else mentioned that he made a lot of frames for the British Paralympic team. Gonna see if I can get a direct contact for him in case he remembers anything about the build

 

[juice.bikes]

I have a 731 frame by Rixon. I’ve owned just about every iteration of Reynolds steel tubing and 731 is the best, IMHO.

Nice! I don't think you're wrong. I wonder why Reynolds stopped producing it. Also read somewhere a couple nights ago that Dave Yates said "it was a tubing time bomb".. wonder what that was all about!

 

[juice.bikes]

Had a rummage around some boxes for potential parts for this. The Hope Ti Glides I have are 28h and laced to Mavic CXP30s which are too deep for this build, so might mean a bit more work sourcing rims in the correct spoke count. Rim wise I was thinking something like the Campagnolo Ypsilon but already have those on the Rourke so leaning towards the Mavic CXP 12, 21 or 23 instead.

The CXP11. 20mm wide, 20mm high

The CXP21. 20mm wide, 20mm high. Machined.

The CXP23. 19.3mm wide, 23.6mm high. Welded + machined.

Some of the above are available online from those NOS resellers in Europe but aren't cheap.. don't really want to go any deeper than 25mm and want to avoid having to buy other hubs.

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I already have a pretty standard Flite on my Rourke so thought to source something else for this, spotted a perforated Flite on ebay a couple of days ago and luckily won the auction but the rails would need to be switched out for a titanium version at very least. Luckily I have a spare set of rails I used for the Kevlar saddle but I had to cut them down a bit to fit so not sure if they will fit - the Carbon rails cracked a long time ago which I will try to fix this winter :-(

Another thought I had was to use the carbon version I had on my track bike beater from way back but pad it with some foam then steam off the perforated leather and glue it onto that instead.. but this kinda depends if there is any difference in size. Is a stripped standard padded flite the same shape as the Carbon flite? we shall see.

Anyways, sunday rambling over.

 

[sjcprojects]

That's funny, you outbid me on that perforated Flite! Actually it's probably a good thing because I'm going to try renovating a saddle instead, so that will motivate me do it...

 

[juice.bikes]

That's funny, you outbid me on that perforated Flite! Actually it's probably a good thing because I'm going to try renovating a saddle instead, so that will motivate me do it...

ha! was at the top end of what I wanted to pay for it tbh. Wild how much some of the NOS ones go for. Def do it! let me know how you get on.

 

[ChromeChainstay]

i use classic and team ti flites on all my bikes, in all their configuations. no cutouts and no carbon rails • since 1990