boy"O"boy's 1989 Serotta Off-road Pro-flex prototype

[boy"O"boy]

Hi all. Thought I'd start a separate thread for this one rather than add to my other Serotta Off-road Pro-flex thread here -

https://www.retrobike.co.uk/threads/boy-o-boys-1990-serotta-offroad-pro-flex.462386/
The keen eyed readers of that thread will notice on page 3 that @Cristian-T shares a pic of his Pro-flex that is 1 of 2 prototypes. After chatting back and fort, Cristian asked if I'd like to buy this one as his workload meant he was unlikely to get round to restoring it.
We arranged to meet at Cristian's shop so I could also see his 'retro museum' of equally rare Muddy Fox bikes and a 1989 Ridgeback 602 LX.
Brilliant to meet up and trade retro bike tales with as well as being a helpful and extremely knowledgeable guy. I promised to start a thread for this and keep the updates going, so here goes......

Cristain mentioned on collection that the Pro-flex was in 'barn find' condition.....he wasn't far wrong! The first thing I discovered as I loaded it in the car was the LH Ritchey true grip had turned to mush and promptly got it all over my hand!

I've marked it as 1989 as a prototype it would pre-date the 1990 production versions.

So here are my 'as bought' pictures once back home.

As found condition


Prototype Rear swing arm has extra brace


Very rusty flex-stem. Handlebars seem bent on one side.


Non-drive crank missing.

More updates to follow
boy"O"boy

 

[boy"O"boy]

Let's start with the Jan 1990 MBUK ad that was the inspiration and start-off for my other build thread.




As mentioned by @Once A Hero and @pete_mcc in the other thread - there are some key differences over the 'limited' production versions. The main one has to be the brace on the rear swing arm.


Next is the treatment of the seat clamp.
- On the production it's a removable seat post clamp.
- The magazine ad has the seat tube 'butted' and the integral clamp is rearward facing.
- This prototype has the normal seat tube as production but the integral clamp is front facing.


The swing arm support/ down tube - seat tube support brace is horizontal. On the magazine ad, it dips downwards. It also has the pivot placement below the brace. This prototype and production have the pivot above.


This rules it out as not being the one from the magazine ad, This is most likely the other 'medium' prototype if it is 1 of 2 ......but the early magazine articles I've posted in the other thread show a large/XL version.

boy"O"boy

 

[boy"O"boy]

What other differences are there versus the production versions?

Well, from what I can see so far without stripping it down.


The true temper fork has a much narrower crown that the production version. Maybe this was done for tyre clearance? - from research on my production one when I was searching for a suitable fork...the one that I ended up matching with was a 1" true temper fork from a slingshot.

The decals are Daihatsu and Off-road.
This could suggest it may have been a team bike....but if I'm honest with myself, the Amateur nature of them suggests that these could have been applied at a later date to make it look like a team bike?

It is most likely the 'prototype' that is mentioned and pictured in the 'teamsters' article from June 1990 MBUK. If you look closely, you can just about see the extra swing arm brace (although it's easier to see it when reading the print of the actual magazine!)
I don't think it's an actual team members bike though....when you look through the Zoom race pictures of Carl Sturgeon and team, the bikes they are all riding by then don't have the braced swing arm.

All thoughts and opinions welcome. I'm hoping on the input of the collective to help me decide which way to go with the restoration of this one.

Cheers
boy"O"boy

 

[27motorhead]

Not much to do then!!!

Another thread I'll be looking forward to following!

Hoping to get to @Cristian-T shop one day as he's not far from where my older brother lives...

 

[boy"O"boy]

Not much to do then!!!

Another thread I'll be looking forward to following!

Hoping to get to @Cristian-T shop one day as he's not far from where my older brother lives...

Cheers @27motorhead
This is a full blown project - will update what needs doing in another post but this is possibly the worst condition bike that I've taken on. A true rusty barn find in every sense of the definition....but I believe it's Providence makes it worthy of bringing back.

As for Cristian's shop - if you're near pop in.... it's well worth it. I took a 180 mile round trip just to pick up!
I took the 'production' Serotta Pro-flex with me to show it off... But ended up talking retro and discussing the Muddy Fox and Ridgeback most of the time! Great guy....loads of retro info learned too.

Updates to (slowly) follow.

Cheers
boy"O"boy

 

[pete_mcc]

Ooooooooo, nice!

 

[27motorhead]

This is going to be a very interesting restoration. Depending on it's origins and provenance it might just be a clean it up to retain originality as opposed to a full respray and new shiny bits? Already lots of detective work going on which I love!

 

[boy"O"boy]

Ooooooooo, nice!

Becoming a familiar theme with my collection - restore one then get offered another which is too good to pass up/ deserved of restoration....and before you know it....I've ended up with several doubles of a particular model.

This is going to be a very interesting restoration. Depending on it's origins and provenance it might just be a clean it up to retain originality as opposed to a full respray and new shiny bits? Already lots of detective work going on which I love!

@27motorhead
Certainly is!! As much as retaining original paint sounds appealing, given it is one of the prototypes but has no team rider associated with it....I'm going to mull this over for a bit in decision of which way to go.
The fact that the seat post is well and truly stuck in the frame may have some influence on the final outcome depending on the removal technique. I've not done a stuck seat post before so I've been reading up on removal methods here.
It's a challenge I'm willing to take on given the rarity.

There's a lot wrong with it at the moment.
1 - Stuck Seat post
2 - Terrible bubbling of paint and rust coming through ( who knows what's under there given the other one had hole repairs done on the bottom bracket area)
3 - Rear elastomer missing / pivot bearings corroded
4 - Non original mis/matched wheels
5 - Bent handlebars/ very corroded + faded flex stem with no elastomer
6 - Most of XT group set is there....but some parts replaced with alternatives as they wore out.

In all....True barn find condition!
I'll try and save as much of the original as possible but some parts will need replacing. At least it's easy to find M732/M735 XT this time and not XC pro.

Attention has moved over to the Ridgeback at the moment. Expect slow progress!

Cheers
boy"O"boy

 

[pete_mcc]

With all those extras decals, that has to be a team ridden bike, they look too random to be someone putting them on to emulate a team bike.
And maybe this bike is earlier than the advert one as the butted section looks to strengthen up the weak spot on your frame which looks to have a crack under the qr?

So what you have is a rarer version of a rare thing?

 

[Once A Hero]

@boy"O"boy is there any evidence of the one in the advert actually being in existence still, or even any others exactly like it?
You've pointed out the differences in the seat clamp arrangement, seat tube and of course the dipping swing arm pivot tube, but I also note the advert bike has the rear mech cabling routed below the swing arm rather than above it as is the case on both of your frames.

Any chance you can give us a side by side pic of your two in their early stages? I keep flicking between your '89 and '90 threads and now my brain hurts