Decoding Marin frame numbers.

Tootyred

Senior Retro Guru
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What brought Retrobike to my attention in 2010, was a search for info on marin frame numbers and the 2008 post which has gone on ever since!


However, ive always been concerned about the number of people on the thread saying the system "dont work for them". Given the rise in demand, interest and frankly prices over the last 2 years, i thought i might spend a bit of time looking into WHY it wasn't working for everybody.

Having owned several marins, including some 80s ones, I very soon realised that most of the confusion and problems arise between 90 and 93 models. So I set about " collecting" 50+ frame numbers and model info from you guys and ebay sellers.

Marin have come in for some serious berating, about this, but my realisation of late was that actually they had it pretty much right, it just how you read the result that may be at fault.

So here is our update...this may be old news to some, but might be helpful new news to others.

Thanks to "marc two tone" for his help

As with everything, im only human, if ive got it wrong or you have additional info to share please do so to help the group and update the thread.
 
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Tootyred

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There are 4 distinct sets of marin frame numbers between 1986 and 2004

So. ( dates stated are purely to identify the groups not an exact cut off).

1st Group A ....These are 9 characters long. Consisting of 1 letter followed by 8 numbers. ( roughly pre 90)

Example M91554037

M = factory of origin
9 = year of construction

Rest of the number seems to have no relevance to anything and i assume its marins code for batch etc. There is no consistent indication of model, month or date so far

So the above bike is a Marvel built 1989 bike.


2nd Group B ....These are 10 characters long. Consisting of 1 letter followed by 9 numbers. ( roughly 90 to 91)

Example M905540374

M = factory of origin
90 = year of construction

Rest of the number seems to have no relevance to anything and i assume its marins code for batch etc. There is no consistent indication of model, month or date so far

So the above bike is a Marvel built 1990 bike.


3rd Group C..... These are 9 characters long. Consisting of 1 letter, followed by 2 numbers, followed by 2 letters, followed by 4 numbers. (Roughly 91 to 93)

Example M21BE0069

M = factory of origin
2 = Model code
1 = year of construction

The rest is marins code and i can find no relevance or pattern to show anything else.

In this era, with 2 letters the hierarchy is...

1 = team marin 2 = pine mountain 3 = eldridge grade 4=bear valley etc.

So the above bike is a Marvel built, pine mountain, from 1991.......No sizing in this code.


4th Group D. These are 9 characters long. Consisting of 1 letter, followed by 2 numbers, followed by 3 letters, followed by 3 numbers. ( roughly 93 on)

Example F13DAC016

F = factory of origin
1= model code
3 = year of construction
C = frame size

In this era the, with 3 letters the hierarchy is....

1 = team issue 2 = team marin 3= pine mountain 4= Eldridge etc.

So the above example is a Fairly built, team issue, 1993, size 17"

The sizing code as far as i can work out is ...a=14 b= 15.5 c= 17 d= 19 e=20.5

Things to remember.....

1.Titanium frames are not included in this system.

2.Early monostay team issues carry their own numbering system, normally starting TET.....

3.There are a few team issues with 2 letters at the start of the frame number.....its not many, but my theory is marin did this to NOT upset their numbering system.....this was done uptill the point the code changed to the " group d" system (when team issues got the " 1" as a model denominator). Marin could not give it a "1" in the "group c" system as this spot was taken by the team model.

4.This system relates, i believe, to steel frames only. I did not look at alloy frames, but it seems they carry a slightly different numbering system.


The original post in 2008, didn't take into account the change in the number of letters, which is key, although several posters did point out the change in lineup would effect the model number.

The system above seems to resolve many of the issues encountered on the original 2008 posts.

Imo, the serial number is much more indicative of the model rather than the physical attributes of the frame, as marin did have a habit of having differing model specs dependant on world territory. So looking at a catalogue from the uk, could lead to mistakes if the bike came from america or japan for instance.

I have not found any real evidence of frame sharing....ie an frame stamped with an identifying number of an Eldridge, having factory decals of a bear valley on it.....i believe, imho, this belief has sprung from misinterpretation of the model numbers and the fact that some groups of frames are basically the same.

Like i said i hope this helps.
 
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Tsundere

Fat Chance Fan
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My Muirwoods is exactly as listed in the 1990 catalogue...
Muirwoods 1990.PNG
The frame number also appears to have pre 1991 characteristics, ie 10 characters - one letter followed by 9 numbers, assuming that last mark is another poorly stamped number (6, 8 or 0?), and yet the year indicates it was made in '91.
muirwoodsfn1.png

So if it is a 91 frame, and that last mark is just a remarkably number like dent, and therefore the frame number has only 9 characters as per pre 1992, where are the letters? And why were they making 1990 spec bikes in 1991?
🤔
I am still confused.
 

marc two tone

Retrobike Rider
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It's good that you alert this, as it helps us tighten the net and gain a better logic. We (uk) got the light zolatone in 1990. I've not got to the bottom of which countries got supplied with brightly painted bikes.
Where are you based tsundere?
 

Tsundere

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It's good that you alert this, as it helps us tighten the net and gain a better logic. We (uk) got the light zolatone in 1990. I've not got to the bottom of which countries got supplied with brightly painted bikes.
Where are you based tsundere?
UK, I bought the bike from the original owner, also in the UK. He said to me he believed he got it in 1989, but didn't seem completely certain about that, just to throw more mud in the water 😁
 

marc two tone

Retrobike Rider
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Right now, I can only expect it's a 1989 (put for sale 1990) and the other numbers dont mean a great deal, I expect, frame size, etc....hidden there.
Tootyreds' pre 1992 still fits for your bike as letters are involved, thus eliminating as 1991.
Your code is one letter, then all numbers.
My cash (20p) is that you bike is 1989.
I do agree that extra code deciphering is needed for that year.
 

Tsundere

Fat Chance Fan
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Right now, I can only expect it's a 1989 (put for sale 1990) and the other numbers dont mean a great deal, I expect, frame size, etc....hidden there.
Tootyreds' pre 1992 still fits for your bike as letters are involved, thus eliminating as 1991.
Your code is one letter, then all numbers.
My cash (20p) is that you bike is 1989.
I do agree that extra code deciphering is needed for that year.
It's amazing that there is so much unknown about something so recent, I mean we decoded the Hieroglyphics and the Rosetta stone but still can't quite figure out some bike frame numbers 😶

But this kind of mystery is part of what makes this hobby so engrossing, everyone loves a quest and these types of challenge are constantly being thrown up on here, Godspeed to all retro bike archaeologists 💪🧐
 

Tsundere

Fat Chance Fan
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Just a theory - Could it be that Marin placed advanced orders for frames, perhaps as a way of reducing cost per unit, but sales for 1990 surpassed expectations and they were forced to break into stock earmarked for the following season? So this could have been a frame made in late 1989 but originally intended for release in 1990/91.
 
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