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

[boy"O"boy]

So.
Another bag of Haribo gets a 2nd go at the seat tube hole repair. Filed back and sorted, it's then into etch primer. This was then followed by several coats of filler primer, plenty of wet sanding working through the grades to smooth the imperfections.
White primer was used as laying the red down on a grey primer would slightly darken the colour matched to original red.
Lots of little 'pock marks' on the top tube filled up by the primer coats.




Primer coats taken right through to 1200 grit smoothness.




Finally. Pleased with the Primer coats, it's into the 1st pass of red.
Red was Colour matched by paint store in Leamington. Note they've actually labeled it Offroad / Pro flex red.




Couple more coats and then onto the 2K Lacquer finish. Starting to come together slowly.

Cheers
boy"O"boy

 

[Thias]

That red looks great!
How do you paint the parts of the frame that it is resting on? Did you hang it on something and only put it down when it was dry?

 

[boy"O"boy]

That red looks great!
How do you paint the parts of the frame that it is resting on? Did you hang it on something and only put it down when it was dry?

@Thias Good question!
So....it was painted upside down 1st. This was allowed to dry. Being a solvent based paint, it cured pretty quickly. It was then turned the way you see in the pics and painted again.
It was allowed to cure over the weekend and then wet flatted with 1500 grit today and painted standing upright. The colour is actually flat when it's dry, not shiny as you see it in the pics.
It gets a grey scotchbrite pad next and is then off to the paint shop to get a clear coat with 2K lacquer in a temperature controlled booth.
The paint shop at work doesn't have the time to do all the prep work I've done here.... it's fairly easy to get someone to clear coat as it's added to a vehicle exterior that's already going through the paint shop and the lacquer is already in the gun.

More painted pics to follow soon.....then onto the best bit! Assembly

Cheers
boy"O"boy

 

[boy"O"boy]

Hi all.
The next update has taken a little longer than expected. It's taken a few weeks for time/space to become available to apply the 2K lacquer in the paint booth. Finally, it's done and the frame is back home ready to start the build.


It's taken some time to get to this point, especially with the seat tube crack repair and the rust hole near the bottom bracket, but now the paint is finished, the repair isn't visible at all.


So, all bits done.
Even the original flex stem has been revived from it's rusty state on page 1. I've also been trying to preserve as many of the original components from the rusty barn find as possible. More to come on that though.

Now onto the build. Updates to follow as they happen!



Cheers all.
boy"O"boy

 

[boy"O"boy]

Hi all.
Progress has been slow on the prototype. After getting all the parts back home, it's sat for a couple of weeks before I've found time to start reassembly.

First up - the MK2 Flex stem. Pleased with this one as I was able to salvage the original one from it's ratty state. Here's a start off picture 1st to show how far it has come.


And now .....next to another faded original one I have that has been cannablised as a parts donor for both Pro-flexes




boy"O"boy

 

[boy"O"boy]

And onto the main build.. ..


The wheelset was built by myself - Araya RM17's on M730/M732 XT hubs. The tyres are the Ritchey Z-Max from the other Serotta Pro-flex. That one is now shod with a nice pair of Tiogas


Fully restored MK2 flex stem with True temper bars. 1" Shimano XT headset is NOS


@fguki
The elastomer stack looks spot on to the original advert picture. Lots of effort went into matching these from the Catalogue picture.
Thanks again for all your help with this part


Seatpost clamp now fully repaired and crack free! Post is a NOS Shimano M730 XT 26.6mm
Fits absolutely perfectly. It's come a long way from the seized post nightmare at the beginning of the thread.


The rear of the Prototype looks tidier than the top clamp of the production version. Judging by the crack that was repaired though, this was a weak point that had been resolved by the time the Serotta Off-road Pro-flex was finally available in 1990


Space in the Man cave is filling up fast ... especially when you have 2 of the same bike!
Once finished - I'll do a comparison of the key differences of the prototype Vs production.
Once you start looking closely (with a beer in hand) there's a lot more than you'd initially think.

Hopefully some more progress pictures to come soon.

Cheers
boy"O"boy

 

[boy"O"boy]

Hi all.
A sunny Saturday afternoon and a bit more time to progress the build.
Decals now on
Cantilevers polished and installed - pleased with these as they've been salvaged from the original barn find. They had been sprayed rattle can Matt black, but underneath were the very poor condition anodised black. Went with a full strip down and polish. May revert back to black in the future, but for the time being, I quite like the polished look.
Gears cabled up and rear mech working
Pleased with this too as the rear mech was salvaged from the original bike.

To do -
Front mech cable up. Shifter missing barrel adjuster.
Rubber cap to protect open end of swing arm. Going to be made from a cut down chair foot rubber. - more to come.

Here's a latest update.... almost there.








And with it's 'production' sibling.



Cheers all.
boy"O"boy

 

[27motorhead]

Great progress and looks amazing!

 

[JCS]

Great job you’ve done there. What a transformation from when you first got it.
It’s like one of those ‘spot the difference’ competitions when you see them side by side.
I wonder if the ride feels any different between them.

 

[boy"O"boy]

Great progress and looks amazing!

Thanks
So close....but it has to be rideable to be finished! Having a prosecco cork wedging the front mech into middle ring position won't cut it for the finish! - not far to go though! Needs some better pics too.

Great job you’ve done there. What a transformation from when you first got it.
It’s like one of those ‘spot the difference’ competitions when you see them side by side.
I wonder if the ride feels any different between them.

Thanks! - yes, it's been a hell of a journey from when I first got it from @Cristian-T this time last year. I've learnt a few new skills by restoring this one which is always good.....but I don't want to do another stuck post or seized bottom bracket shell again!! Repairing the crack and rust hole was satisfying but couldn't have done it without some specialist help.
I'll drop 2 images here to see how many differences people can spot. Apart from the obvious groupset and wheels - the frames have loads of differences between them.
I'll do a comparison when this one is finished.

Prototype 1 of 2

Serotta 'production' batch of around 80 examples. Frame no. 54

Cheers
boy"O"boy