Frame weight… it’s often talked about, requested and used as a measure to try and determine tubing type. From my own experience I can see several factors that affect final weight and I frequently see through my own documentation process that frame weight can be very random and time and again I see that it can be impossible to correlate frame weight to frame size to frame tubing.
It was just another night in front of the television when an email dropped into my Inbox regarding an SBDU frame, this is a situation I’ve been in a few times now. Another frame with a case of mistaken identity came up on my screen, actually, this time it was more a case of confused identity. A frame that looked like a Panasonic/Weinmann but with the name of Wes Mason emblazoned on the tubes. After a couple of emails a deal was done and the frame was with me two days later.
Every new addition gets a good clean and although it was already looking quite good, SH377T still needed a bit of work. Wet oil and grease on the surface of a tube will attract dirt and dust, and that is all that was covering this frame. When a frame is clean I can measure and document it. SH377T is a curious frame and I’ve looked forward to getting to this stage in my process.
eBay… it is a place I try to avoid. I like to find bikes and frames that haven’t had much exposure to the internet. eBay links containing interesting vintage bikes are shared across social media, and before you know it, the item has been seen by thousands and hyped up to a point that the auction escalates and bidders get into a frenzy pushing the prices up beyond anything sensible. I enjoy the hunt, searching and discovering SBDU bikes that have been hidden away. But I do keep an avid eye on eBay and every now and again a little gem crops up to pique my curiosity. SH377T was listed with no reserve and a low starting bid so I saved it into my ‘Watch List’ thinking it would go the way of so many others and spiral out of control… but it didn’t!
The SBDU seemed to stop stamping their H reference on frames towards the end of 1979, meaning the frames coming out of Ilkeston at the beginning of the 80s would only have the SB frame number stamp and nothing to identify a frame as somehow different. I guess from this point on, the only reference to a specific build or geometry would be shown on the paperwork and build sheets that followed the frame and fork through its production, eventually ending up in Ilkeston’s records. If your frame does have an H reference then you still really have no idea what the ‘H’ was all about unless you have original documentation; that is why I try and measure, document and figure out all my frames.
In the beginning there was Metric Reynolds 753 tubing, and then later in 1982, a new Imperial Reynolds 753 tube was introduced. The new tube, called 753R, had different diameters, different gauges and was slightly heavier than the original Metric tube. And that’s how it was always known… Metric 753 before 1982 and Imperial 753 available after 1982. That seems quite straightforward doesn’t it?
There has always been lots said on the subject of Reynolds 753, and that doesn’t surprise me. This tubing had such an impact on the sport of cycling; the frames and their riders were breaking records before anyone even knew 753 existed! 753 frames are still sought after 40+ years following their introduction. You can’t go a day without the subject of 753 cropping up on the internet and the online debates and discussions mean that there are always stories and different opinions. But are these stories real and are the opinions accurate? What is truth and what is myth? What are these stories? Have I done enough research and accumulated enough data to either prove or debunk them?
This post isn’t necessarily about the SBDU, but I thought I’d write it as I get asked regularly to confirm seat pin sizes, or to try and decipher what an SBDU frame might be made from based on the seat pin and tube size. After collecting several SB frames over the years, I’ve seen lots of different seat pin sizes used in Reynolds frames. I have seat pins ranging from 26.6 to 27.4 – and 753 frames with 4 different size pins. That demonstrates just how varied their tube gauges were. So here is a little post that lists some of the most common seat pin sizes and the associated Reynolds tube gauge (wall thickness).
There are many stories about the SBDU and even more about Reynolds 753 tubing. Most of these stories travel the internet, changing and evolving each time they are told. Something as simple as which seat pin size should fit a 753 frame is one of those stories. It causes the most confusion and creates some of the longest discussions whenever it is raised. Everyone seems to have an opinion about what is right; few ever seem to agree. My latest addition, SB3800, means that I may now have a couple of frames that could finally settle the seat pin debate.