There is no doubt that this bike is fitted with a Campagnolo Super Record 50th Anniversary Group. There is also no doubt that this is a Reynolds 753 Ilkeston Raleigh SBDU frame. And there is indeed no doubt that this frame does have an SB frame number. So why am I confused about the frame number?
This is a strange blog post to write because at the time of writing this post, I don’t actually own this bike. I want to, but at the moment, I don’t! So it is kind of like an honorary post for this bike.
A Bit of Background…
Starting With My Own SB6398
Every story has a beginning, so let me start there.
In August 2016 I bought SB6398 which is a Reynolds 753 Raleigh SBDU with a Campagnolo Super Record 50th Anniversary group. That bike is special in three ways.
- It’s an Ilkeston SBDU 753
- The bike is fitted with a Campagnolo Super Record 50th Anniversary group
- It was built for a member of my old bike shop and has its original DENTON livery
This is SB6398 following the preservation work I carried out on it. Apart from the bar tape and lever hoods, SB6398 is completely original..

In the back of my mind, I had SB6398 categorised as a ‘one off’. I really didn’t think there would be another bike out there that was similar. But I was wrong!
SB4522
A short while after I finished that project, another black DENTON/SBDU with a 50th Anniversary group popped up on the internet. SB6398 was so unique that several people thought I was selling mine, but I wasn’t, this was another one.
The frame number of this new bike wasn’t listed but it was close to me so I visited. The number on the BB was SB4522. My guess was that SB4522 was built for Colin Davison who was the owner of Dentons. SB6398 was definately built for a guy called Hughie who worked at Dentons. This 2nd bike is certainly Colin’s size – I built quite a few bikes for Colin over the years and this one fits with what I recall about his sizing.

I had just added SB1861 to my collection, so at the time, I couldn’t afford this one, and had to let it go. But the SBDU world is a small world, and I was sure it would pop up again, especially an odd one like this.
SB4522… Again
A short while later, my prediction came true and SB4522 re-appeared. This time it was looking a lot cleaner, but it was more expensive, and sadly, based on that new price, I let it go for a 2nd time. Something was telling me that this bike was never going to be mine. I did however give some advise to the guy who went on to buy it, and it is him that I am buying it from now.
But before I do buy it, he has kindly let me have it ‘on approval’, so I can take my time and have a good look over it.
On The Workbench…
First Impressions
This bike is clean. The white Turbo saddle and new white bar tape set this bike off and they match the black paint and white transfers. I’m not usually a fan of white saddles but I guess this one fits.

From my previous viewings, I already knew that this bike had a few bits that weren’t right. The brake shoes were missing the angled wheel guides, that’s nothing to stop the brakes functioning, but aesthetically they would be better with them. The seat pin is not from the 50th anniversary group. It is a standard Super Record pin. Nice, but not correct. One additional point I noticed was that the inner chain ring was sitting very close to the chainstay, and a close look at the BB cups showed that they weren’t the Nuovo Record ‘rifled’ type of cup that I would expect to see. The small amount of axle showing between the cups and crank was also the wrong colour. Many assume that the 50th anniversary group used a Super Record Titanium BB, but they didn’t, it was typically supplied with a std steel Nuovo Record BB set.

This bike has been ridden. That might sound like a strange statement to make about a bike. However, many owners of 50th anniversary equipped bikes sometimes hesitate to ride them. Many owners of this group might not even remove the group from the box and mount the parts to the frame. But in this case, the bike has been ridden. The MAVIC GP4 rims laced onto the 50th anniversary hubs have a good amount of wear, the brake blocks are well worn and there is plenty of rub on the cranks.

The paint condition and the appearance of the components is really good. The paint is clean, shiny and only has a few marks with some small signs of corrosion. The components are equally as clean and just as well maintained. The bars and stem look either new or they are mint condition used parts. There is a tiny amount of play on the rear hub and the front hub is silky smooth. The brake lever hoods have also been replaced recently.

Initial Thoughts on Frame Date
The frame number of SB4522 dates this to the first half of 1981. Based on that frame number, date and certain transfers, this would be a repaint. And that is very much the way I’ve always looked at this frame.
Stripdown
Frame and Parts
I’ve been granted so much freedom to do what I want with this bike, so taking it apart is fine. My aim is to check things such as…
- BB threads. Are they good
- Tubing. Does each tube look ok, bent, cracked, pitted, rusted, are the pins present
- Seat pin. Looking for correct size and seat lug damage.
- Fork condition. Does it have corrosion? Is there a number, is it random or does it match the frame
- Evidence of previous paint
It’s always good to open the Campagnolo Toolkit, the perfect tools for this groupset.

The chainset and pedals came off without a problem…

And just as I had thought, the BB is wrong. The axle has a shield logo and has the markings ’68-SS G’. A quick look in the Campagnolo Dealer Catalogue shows that this is an Athena BB from circa 1988.

The seat pin is ‘26.8’ but it’s slack. I need to check the seat pin and frame size before reassembling. The seat fastening bolt is an original SBDU Ilkeston fitting but could do with a washer fitted.

Through the empty BB shell, I can feel pins in each of the chainstays and at the bottom of the down tube; all the tubes are good, there are no obvious signs of damage to the paint that might indicate a problem with a damaged or rusted tube. The frame ends are period correct Shimano vertical and drilled in the SB 753 period style. The BB cups came out nicely and the BB thread felt ok. The Cinelli BB shell is also correct and in good condition.
You can clearly see the ‘SB4522’ frame number stamped along the drive side of the shell. The paint is nice and crisp over the stamped numbers.

Fork

The paint on this fork column is a good sign of SBDU paint. I’ve seen so many original paint SB frames to know that Ilkeston painted forks usually have a couple of inches of paint up from the fork crown. The Cinelli SC crown is also period correct. There is a small amount of surface corrosion on the column but this cleans up easily with a wire brush.
Threading
A few new SB owners get in touch with me with images and questions about their new purchase. I often see Italian threaded headsets and French threaded hubs on these bikes. I’ve also seen a French thread SBDU BB shell. So threading is always worth a check, never assume. The BB on this frame is fine, it is std 68mm English 1.370″ x 24tpi thread.

The hub has an English thread (1.370″ x 24tpi). The Maillard freewheel is ISO (1.375″ x 24tpi).
This Campagnolo Super Record headset is English (1″ x 24tpi). Just as a side note, the 50th Anniversary Super Record group didn’t have a dedicated headset, the headset was always just a std Super Record part. Part No 4041.
Thread Interchangeability
My personal preference is to fit an English thread headset to an English fork. That would be a ‘CLASS A’ fit. Lots of others may say that it doesn’t matter, an Italian thread headset on an English fork is fine and works. And there is some truth to that. An English thread is 1″ x 24tpi whereas an Italian headset thread is 25.4mm x 24tpi – surely the same thing? 1″ = 25.4mm… right? However, there is a slight difference in thread angle. So although the diameter is the same, and they both share the same amount of threads per inch, the slight difference in thread angle makes English/Italian a ‘CLASS B’ fit. A CLASS B fit means that it will fit and be serviceable but there may be problems.
A Super Record headset is very lightweight with soft threads, especially on the top nut. If you don’t have a perfectly clean fork thread and an excellent condition headset, the headset thread might get damaged.
So far, everything on this bike, apart from a couple of parts, is looking ok.
But Now For a Problem
Fork Stamping
Dropping the fork from an SB frame is always interesting. Will it have a number, will it have letters, will those letters be initials, what if it doesn’t have a number? These are all questions I have in my head just before I see the fork column.
As you can see, this fork does have a number but the images below show differing numbers on the frame and fork.

My initial reaction was one of disappointment, thinking that the fork was a replacement from another frame. But the ’22’ on the end of each number was too much of a coincidence and too similar. Then my second thought was that they had mistakenly stamped the fork by stamping the ‘5’ first followed by the ‘4’. However, the more I look at the frame, little details and design cues are leading me to think that it is probably the frame that has been stamped incorrectly.
Final Thoughts…
The biggest question with this bike has to be, is this SBDU Reynolds 753 frame from 1981 (SB4522), or is it from 1982 (SB5422)? I really need to check all the details and do some research to answer that one – I’ll keep my findings for another post.
So what were my overall thoughts? Well, it is a beautiful frame with great paint and an amazing groupset. Therefore, regardless of the frame number question, I think I need to buy this one! Destiny keeps putting this bike in front of me, it wants me to buy it…
Hi Neil.
Another interesting post. It posed a question for me in the fork stamping; what is the significance if the fork has letters versus numbers that may or may/not as in this case match the bike stamp? The fork on my SB2257 is stamped POLY. Does that mean anything?
Looks like a lovely bike for the collection which clearly you have some connection with.
Regards
Paul
Hi Paul
The fork stamping that the SBDU did clearly went through an early patch where different ‘random’ things were stamped. Some early forks had nothing, then some appeared that just had ‘SB’, then a few had letters, often just 2 letters. Some had NED which is often seen as ‘Netherlands’ and some have ‘POLY’. During the period where the ‘H’ reference was stamped on the frame the corresponding H ref number would be stamped on the fork. It took a while for the SBDU to settle on the frame number (without the SB prefix). And even then there are anomalies. Most people expect the fork to have the corresponding frame number, but that isn’t always the case. I’ve got forks that have the frame number stamped but also have another number that has no relevance to the frame at all. SB6398 has ‘6398’ stamped on the fork but also has ‘2104’ stamped on the fork – I can’t find a link between SB6398 and 2104? I’ve often wondered about the forks that have ‘POLY’ stamped on them. ‘POLY’ can mean ‘Many’ or ‘More than one’. So does that mean that batches of forks were built at some point that could be used for many different frames – a generic fork? There are a few frames in your frame number range that have the same ‘POLY’ stamping. There are lots of the things about the SBDU that we will never understand!
Cheers
Neil
Hi Neil,
Could it be back then, that the SB serial numbers, though important on the BB shell, were not considered important enough on the steer-tube, if steer-tube slightly miss numbered.
Not sure, builders back then could have known how important matching numbers would be, or mean later on, to collectors (or that they would be analyzed as they are by us).
My 1975 SBDU #107 has only “SB” (no numbers) stamped on the steer-tube, just above the crown. Have another SBDU (1181) that came to me from the original owner, but it had a stamped right crank-arm, but the other stamped as originally built (Campy miss-match just a reference to lack of matching number’s importance in general).
Bet your fork is original to frame, with just the two numbers accidently reversed.
Phillip
From what I know of the build process, the guys who built the fork also numbered the fork. But the frame was numbered by someone else. The frame was numbered at the final check stage, just before passing it over for painting. I’ve got a bit of checking to do to see if it is the fork or the frame that is wrong – I definately think the fork is correct to the frame, but I’ll try and check that too if I can