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

[27motorhead]

You can just drag images off the threads onto your desktop and then drop them back where you want...

 

[27motorhead]

Sorry I should have put the advert one up in my post too! Now I can't seem to edit it?

 

[27motorhead]

Have had to delete it @Once A Hero so I could add the advert. So here it is properly...

Advert...

1989 Prototype/Team bike?

1990 Frame (not original forks)

 

[Cristian-T]

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.
View attachment 863638
As found condition

View attachment 863639
Prototype Rear swing arm has extra brace

View attachment 863640
Very rusty flex-stem. Handlebars seem bent on one side.

View attachment 863642
Non-drive crank missing.

More updates to follow
boy"O"boy

Hey ben! Great to meet you as well appreciate coming to pick it up and glad you liked my little collection.

My thoughts on this bike being the one in catalog photo.. as there seems to be 2 protos, and off-road being a US based company (?!) wouldn’t the catalogue bike be the US based versio, not the Uk (now yours) one ? Just a thought.

I’ll keep an eye on the thread with interest, slightly distracted this week trying to stay in one piece riding in morzine.

Cheers,
Cristian

 

[27motorhead]

@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

Lot's to think about and get your head around. Really interesting project. I'm sure you'll do a grand job no matter what approach you decide to take!

And yes XT vs. XC Pro makes searching for components a lot easier!!!

Looking forward to project Ridgeback too!

 

[boy"O"boy]

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?

@pete_mcc Part of me thinks...
- Yes this could be a team ridden bike, maybe a back-up bike rather than a specific Rider like Carl Sturgeon (The MBUK zoom pics of him riding show him on a non-prototype swing arm though)
- No because the stickers look like they've been placed to cover paint damage. On strip down, there's a lot of evidence of black overspray from a rattle can touch up of the swing arm on the frame.

Earlier than the advert frame? - maybe.
Personally I think this is the next one after the advert prototype though. The horizontal pivot triangle is nearer in design to the 'production' version, the cable routing to the rear mech is also resolved as the 'production' one.
Whilst the seat tube doesn't have the butting the seat clamp is the same as the advert version but the other way round. As rightly pointed out...there is a crack which is probably why the 'production' version has a removable collar as an evolution of this. All guess work mind... Someone out there (probably the frame builder) will know more?

@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

@Once A Hero
Looks like @27motorhead has sorted this for you! Thanks for this!.... I've deliberately tried to keep the 2 build threads separate but as the discussion requires a bit of cross reference with the 'production'.....having the pics grouped together helps explain it better!

boy"O"boy

 

[boy"O"boy]

Hey ben! Great to meet you as well appreciate coming to pick it up and glad you liked my little collection.

My thoughts on this bike being the one in catalog photo.. as there seems to be 2 protos, and off-road being a US based company (?!) wouldn’t the catalogue bike be the US based versio, not the Uk (now yours) one ? Just a thought.

I’ll keep an eye on the thread with interest, slightly distracted this week trying to stay in one piece riding in morzine.

Cheers,
Cristian

Hi Christian. @Cristian-T
Been a few weeks now since I picked up. Hope the riding in Morzine was all good this time!
Was great to meet you in person and chat about the collection. I'd definitely say we share the same tastes!
Family holiday and the re-appearance of another prototype that I had down as lost have slowed any progress on this one. That, and wanting to get the Ridgeback finished!

Agree with your above post that maybe this 'prototype' is probably more UK centric than the magazine advert. Maybe the forward mounting of the seat clamp was a request to prevent mud ingress? - like on the Pace RC100 where it's forward facing. The 'Wishbone' of the prototype swing arm has more clearance too when you look at it next to the 'production'

So....
I've started to take it apart. Before I went on holiday, I opened the clamp wider and poured a load of plus gas down the sides in the hope of it penatrating the stuck seat post.

On my return, I then drilled a hole through the seat post to take a lever bar

Unfortunately....this just ripped the top of the seat post. Onto plan B then ...


Plan B. Take the bottom bracket out and soak it upside down.....
Bugger! Bottom bracket well and truly seized in. I'm going to need to big vice at work....as I've done with previous seized bottom brackets.
OK... I'm going to need to take the fork and swing arm off to get it through the work turnstile.

Damn it!!
Headset seized in too!! With the all over rust and seized components - I think this barn find has either been stored outside for some of it's life or the barn/shed/garage was damp.
With some persuasion, the swing arm comes off to make it more manageable to get it into work!
I'll remove the headset and bottom bracket before returning to that stuck post. May go straight in with the caustic soda technique.



boy"O"boy

 

[boy"O"boy]

More updates.

Seriously rusted brake cable guides.
Cables were well and truly stuck in.

More investigation of frame condition once headset and bottom bracket come out.

Detail of the rear derailleur cable guide on the swing arm. On the 'production' this is a simple ring that the cable feeds through.


Any ideas on the bars?
Original unusual shape or cheap later replacement? With all the true temper links to the frame and fork would these also be true temper?
The weight and level of corrosion on these suggests a cheap Cro-mo bar. I thought they might be bent but they look like a shallow riser bar?


Possibly the worst condition wheel set ever!
Definitely not original.
Rear is M732XT on a Mavic 230 TIB
Front is Exage on Ritchey Vantage. - no saving the hubs on these! They look like they've been dredged from the Canal.



More updates once it's fully dismantled.

Cheers
boy"O"boy

 

[27motorhead]

WOW!

Is it not too late to return to @Cristian-T ??? That's a bucket and some more of worms you have literally unearthed!

There's patina and there's full-on corrosion. You have both going on. Get the BB out. Get the forks and headset out, then it's looking like caustic soda on that seatpost as you don't have much to grip on if you were going to try a slide hammer or a specifically made puller.

It's in safe hands. A PROPER project this one!

 

[mynchiboy]

Tuning in late to this one. I have every faith you'll knock it out of the park again Ben

Don't know if they're any use but I have the renmants of another early flexstem kicking about somewhere.. There could be an elastomer there but I cannot remember. You can have all the bits as karma if you need them?