Frame Weights of Specialist Bicycle Development Unit (SBDU) Reynolds 753 and 531 Frames

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.

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SB7393 1985 SBDU Ilkeston Reynolds 531 Professional Geometry and Design

SB7393 Raleigh SBDU Ilkeston Reynolds 531 Professional 1985 – Geometry and Design

Time Trial frame? Road frame? Or a bit of both? What exactly is it?

SB7393 came with a story that it was built and used for time trials and ridden by a junior. I was also told by Rob, the previous owner, that it was a “lively” ride! It looks like a conventional SBDU road bike, but then again, SB time trial frames can look like conventional road bikes too; and with vertical and horizontal ends as options on both types, it is ultimately down to geometry to unravel the puzzle.

SB9000 SBDU Nottingham Reynolds 753R Raleigh Banana Low Profile Frame

SB9000 SBDU Nottingham Raleigh Banana Reynolds 753R Low Profile Track Pursuit Frame – New Arrival

eBay! Love it or loathe it, every now and then it does serve a purpose.

Personally I loathe it and while I’m definately not a fan, it has actually accounted for a small amount of my new arrivals. I do prefer to collect frames that fly under the radar but sometimes you see a frame that is too nice and too special to ignore. So I watch the bids and try to figure out where an item’s price is going and what, if anything, it could add to my SBDU collection. On balance, SB9000 had more positives than negatives. The benefits I’d gain for my collection outweighed the one big negative which was that it had been viewed by thousands online and I clearly wasn’t the only bidder who wanted it.

SH377T SBDU Reynolds 753 Pursuit Track Frame Head Tube Detail

SBDU Ilkeston Reynolds 753 Raleigh Pursuit Frame SH377T – Cleaned and Documented

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.

SB3505 1980 SBDU Ilkeston TI-Raleigh Team Pro Reynolds 753 Geometry Check

SB3505 1980 SBDU Ilkeston Reynolds 753 TI-Raleigh Team Pro – Geometry and Design

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.

SB632 1976 SBDU Ilkeston 753 Track Frame Angles

SB632 1976 SBDU Ilkeston Beryl Burton Team 753 Track Pursuit Frame – New Arrival (Part Two)

This is post number two looking at new arrival SB632, and I’m measuring geometry. How will this frame measure up? What size is it? How long (or short) is it? What angles does it use? What is the bottom bracket height? Does the fork clearance affect the frame geometry and size? More importantly, will the geometry give me any clues to enable me to pinpoint what this frame is? Lots of questions needing lots of answers!

Oh, and this is also my 100th published TI-Raleigh SBDU blog post! A small milestone that I’m very proud of.

SB632 1976 SBDU Ilkeston 753 Track Fork Details

SB632 1976 SBDU Ilkeston Beryl Burton Team 753 Track Pursuit Frame – New Arrival (Part One)

I’ve had another new arrival, not long after the 753 Dynaflite came into the workshop, I’ve found another rather special frame that just deserves to be in the collection. SB632 is much smaller than anything I would normally collect, but the significance of this frame meant I had to have it.

SB7121 SBDU Ilkeston Reynolds 753T 1985 Silver Solder Head Lug

SB7121 Reynolds 753T 1985 SBDU Ilkeston – Seeking Answers Under the Paint

Sometimes my frames come to me without any signs of originality meaning that I can’t accurately identify them. There is seldom a known history to accompany a 2nd hand frame. SB7121 was a classic example of this. I bought it on a whim, based on a basic description which indicated that it was probably a Reynolds 753 frame. The frame number dated it to 1985 and it had a hand painted finish with ‘Wheel Craft’ frame transfers, but underneath the paint, it was 100% an SBDU. I wrote an initial blog post on the frame but always wanted to come back and dig deeper and take a proper look into what it was.

Dave Yates Frame Building Course Day 4 A Look Around Daves Workshop

A Week Spent with Dave Yates Learning the Skills of Framebuilding – Day 4

Bikes are not much good if you can’t attach cables for brakes and gears, it would also be nice to carry a water bottle or two. That means that day 4 was all about ‘braze-ons’ – those little guides that you pass cables through!

Raleigh SBDU Ilkeston Time Trial Special 753 1978 SB2692 H591 Frame Numbers

The Significance of the SBDU H Reference Frame Number

Realistically, there may not be many ‘original owners’ of SBDU frames – I.E. those people who still own an SBDU frame that they ordered and bought for themselves from Ilkeston. There may be even fewer original owners who have a frame with an ‘H’ reference.