Holdsworth Frame Numbering

[CommanderChuff]

Re:

I think that the second graph with the rising curve looks better from a production volume point of view and more realistic for a business ramping up output. In my experience the supply chain line and manufacturing capability is always the limiting factor in output, which in turn is driven by market demand.

It seems that the 1973 date for the Prof was a bit of an educated guess by the previous owner and may be out by some years. This picture of the back stay tops on the Prof have a pattern which may be indicative of an earlier date.

However, I think that we have exhausted the info for now, so perhaps we should settle for 1970 as the starting point for this block of numbers.

Thanks again for the help and data.

David

 

[dwscrimshaw]

Its a great looking bike!

Just spent morning re-hashing the graphs, still have yours down a 1970.
https://drive.google.com/drive/folders/ ... TNKZkN4TmM

I am happy with the 6 digit numbering so tried to apply similar principles to the 5 Digit numbers taking into account what is known of production in this period. This in now a combination of putting the numbers in sequential order rather than stated date order, grouping them and then adjusting the predicted start/finish points to match what is know on number progression.

Seems a fairly consistent progress of ~1500/yr up to early 60's. Its the restart of the 5 digit numbers from mid 60's that is more problematic, very little good info. All I really know is that the shop had is own numbering during this time so the progression slows.

I think this is as good as it is going to get now without more numbers from 60's. Would welcome any more thought anyone has.

 

[Earl10]

You can add Holdsworth 28134 to the register.

 

[dwscrimshaw]

Thanks added that number. Do you have any further info on this number, do you know which model it is and date.

I was looking at this range of numbers only this morning and if I understand the discussion correctly there was a batch of 300 numbers, 28000 to 28300, issued by the factory to the shop in 1961 for their own builds. What ever this frame is it is likely to be shop built and may have been built in 1962 being somewhere in the middle of this batch.

Any further info you have would be useful.

 

[Earl10]

Re:

It's unusual in that it's an Hellenic frame.

 

[dwscrimshaw]

Interesting, I see you have some response to your post on this to confirm what it is. So as far as I can tell from the frame number this was mid way through a known batch of shop numbers issued in 1961. I therefore suspect it was actually built/sold a year or so latter.

 

[LesArcs]

Re:

Just some further info to add. my Holdsworth frame and forks are no. 33156. As the frame had no decals when I bought it I subsequently sent lots of pictures and measurements to the VCC marque expert who identified it as a Holdsworth Mistral frame set, built in 1966. Not sure how this fits in the list, but the chap who identified the frame said he worked at the Holdsworth factory at the time,miso should know what he's talking about.

Hope that this is of some help.

Paul

 

[dwscrimshaw]

Thanks, I do have this number in the Excel file and had it down as a 70's number from the info I found or could be there was not date so I placed it where I thought it goes.



As you can see in the file I am having difficulty with the post 65 numbers. There are no good fixes to relate this to. All I know is the first 65 number is reasonably accurate and the Shop ran there own numbering at this time so dropping the progress through the numbers.

Prior to 61 I have some good date fixes and it seems to follow the 1500/yr production rate commonly stated. post 65 the number progression seems strangely slow, but ramping up during the 70's. to get these numbers to fit a more linear progression I would have to shift a lot of them around, see graph below. as there are so few numbers to work with it is difficult come to any conclusions.

Your number is therefore interesting in that you have a good date fix. based on my graph as it stands I would place this as 1970. However the linear progression graph below, which is based on a production rate estimated from the lowest and highest number divided by the number of years, put yours around 66/67. Accepting that I do not have a goof fix on the dates your dating sounds good. The problem I am left with is what do I make of the numbers I have? I am inclined to think I need to find some more numbers with good dates to try and get this sorted out.

I will use this number and note it has a good date to come back to once I have some more information.

Thanks again for the number.

https://drive.google.com/drive/folders/ ... TNKZkN4TmM

 

[dwscrimshaw]

Had another look at this using your number and the other good dates. I have been back over some of the others to look at how confident these may be. I have used the April 65 date as a good fix point and looked at the progression across the years to get a yearly rate which is less than the ~1500 used for pre 60's that had the shop numbers included. (Does seem a bit low though) One of the obvious problems with the dates as they were originally is that 1970 and 1973 exceeded the likely production rate for the year.

So trying to juggle all this and re-assessing the date validity I have the linear graph below which places yours in 1967 by my reckoning. I am not in a position to argue with the VCC expert so I guess this is about as accurate as I could hope to get with the info at hand.

Hope it helps, will keep working on it as numbers come up.

 

[dwscrimshaw]

So from your excellent database that makes my Professional (it feels really good to say that, and proud), a 1969 model and not 1973 as Tim was given to understand. Only one year after the World Championship was won on one of these bikes, it makes the purchase of it even better.

Great news, and thank you again for your diligence and work to produce the numbers database.

Hi again,had reason to look at the late 60's graph again as an other good date/number came up, see elsewhere in the thread. I have now put it back in a linear progression and places your bike back a bit further. Accepting the accuracy can be out by a year or two I now make yours end of the 60's rather than 1970. Hope this helps rather than a disappointment.