Another email, another road trip, another bike.
I was sitting with my feet up on holiday at the end of May, just relaxing and watching the boats go by on the Norfolk Broads, when I received an email asking for a valuation on a bike. After a few more emails and some shared pictures, I ended up agreeing to buy it. SB7393 is an original paint SBDU bike built with Reynolds 531 Professional tubing and spec’d with a great selection of parts… and best of all, it is my size, 57cm.
I mentioned in a recent blog post on SB6827 that I was cutting down on how many frames I was collecting and wanted to be a bit more particular and specific this year. However, I’m always on the lookout for something a little different. It was the originality, tubing, colour scheme and parts on this bike that were enough for me to take the plunge and have it.
I’m interested in bikes and frames that can fill gaps in my data and collection, I like something that is original and different and I’m a sucker for stories and provenance and tracing the history back to the original owners. Even though it is looking a bit tired, this bike has everything, and I’m sure there is a gem just waiting to shine here! The story on this one also gives me a clue to the type of frame, but I’ll hopefully confirm that in another post when I strip the bike and measure the geometry.
SB7393 was originally ordered for Time Trials and the new owner competed as a Junior. But after a few years, and finishing university, the plan was to take some time out and cycle from Oxford to China; SB7393 was sold to help finance the trip. It was bought by Rob who was a friend of the owner, and it is Rob that I’ve bought the bike from. He has assured me of a very lively ride! If this does fit the geometry of a time trial frame then it will add another tubing type to my sub collection of TTs, as I already have 531c, 531SL and 753 versions.
The paint scheme isn’t what I would call the norm, it is quite different, the two contrasting seat panels are something I’ve only seen on a couple of occasions. Although the paint in places is dull and there are some rust issues around the fork crown and rear bridges, the paint work should respond to a deep clean with some paint restorer and polishing. I really like the contrasting red head tube and seat tube panels with the grey frame.
Once the cobwebs are dusted off and the rust around the bridges, fork crown and cable stops are dealt with, I’ll see if I can put some shine back into the paint. There are hints that the paint is still good so I’m hopeful.
I’ve got bikes that are equipped with Record, Super Record, 50th Anniversary Super Record, Dura-Ace, Shimano 600EX and Superbe Pro, so SB7393 gives me another, MAVIC. I’m not a Mavic aficionado and I’m also not going to try and spec this bike to be a period correct example, but I’d like to replace the Campagnolo Record brakes with something that fits with the rest of the Mavic components.
The calipers look to be the longer reach version as the brake shoes are right at the top of the slot. They also show the originality of this bike as the small cardboard ring that was used to keep the adjuster in the caliper while they were new in the box is still there – it’s just looking a bit older! The brake lever hoods have been replaced at some point. Some Modolo levers and calipers could be a better option.
A lot of this bike is ‘stuck’ or looks like it will be a problem. I had to remove the front derailleur in order to get the chain onto a chain ring, the rear brake doesn’t move and some of the cables have pulled through the cable stops. The allen key fittings on the rear of the brakes also look like they will be a challenge. But I have plenty of experience and tricks to sort things like this out. This was the fastening of the front caliper on SB3800…
I haven’t tried moving the stem yet but I did give the seat pin a twist and thankfully it moved and came out. The Campagnolo Super Record seat pin should clean up well but I’m not sure about keeping the saddle, that might change to a standard Turbo.
Apart from the rear derailleur and freewheel, which was changed for easier gearing, all the mechanical components are original.
The Simplex SLJ 5500 derailleur was fitted when the original Mavic broke. The BB is Mavic 600RD, the front derailleur is Mavic 810, Pedals are Mavic 640, gear levers are Simplex SLJ (springs still feel ok) and the chain set is Mavic 630 (the narrow font version – not block font). The Simplex levers demonstrate a typical problem that many have encountered, see how the cable end is sitting proud of the recess – these levers need a smaller diameter cable end; if you need to fit a std size cable then you have to grind the end to the correct diameter.
The hubs are Mavic 510 laced onto Mavic MA40 rims.
Reynolds 531 Professional tubing sits in the middle of 753R and 531c; as light as 753R but without the same heat treatment and strength, essentially a “light gauge 531 tube”. The figures below are all taken from Reynolds documentation and they show the same wall thickness shared between 531P and 753R – the only difference I haven’t shown is that 753R used a plain gauge steerer and 531c/531P used a single butted steerer.
The table also shows that the gauge at the seat pin end of the seat tube tube is 0.5mm – this means that on all three tubesets, in the imperial 1 1/8″ (28.6mm) diameter, the seat pin size is the same, 27.2mm.
It also shows the reason why many cannot differentiate between the hand held weight of 531c and 753R – as you can see, there isn’t a great deal of difference in wall thickness meaning that the weight of the same size frame using the same geometry in 531c and 753R is very similar. The significant advantage of 753R was the tube strength derived from its heat treatment. The original Metric 753 and 753T will always be much lighter because of its diameter, thinner wall thickness and the tapering applied to the stays.
SB7393 is the 33rd SBDU bike to be added to what is now a large and varied collection. Some bikes are the wrong size for me to ride but I’ve collected them because of the significance of the features that they demonstrate. The size I prefer to ride is an SB 57cm of which I have a few; I can also squeeze onto a 56 or 58 depending on the top tube length.
Some of my 57cm frames are 100% show bikes and I’ll never ride them. SB4059, SB6398 and SB6827 are three bikes that I’ll never take out on the road. Some may call them ‘wall hangers’ or ‘garage queens’, and I often feel that there is just a hint of jealousy when I hear people call a collector’s bike like this and say that all bikes must be ridden! I’m more than happy to have that discussion with anyone who expresses that kind of criticism for someone who puts so much work, time, effort and money into a restoration. My opinion is, if you want to ride your bike then great, equally, if you don’t want to ride a bike then that’s ok too.
The great thing about my collection is that there are so many, that means that I can get enjoyment from just owning some bikes while riding others, and some are definately ‘riders’. SB3800 is an example of a 57cm 753 Team Pro that fits me really well; SB6560 when it is built will be another 57cm that I can take out, and this one should be a great bike to ride too. I’ve had a quick measure of the top tube and it is short so it will be a good reach and fit for me.
But all that work will have to wait for a couple of weeks until I get a bit more time to tackle the stripdown. Following that I’ll measure and document he geometry before dealing with the rust and paint.