Moulton Deluxe F frame restoration.

After some hunting I found this rather lovely green Moulton Deluxe which I'm planning to restore to use as a commuting bike as well as taking on the Dunwich Dynamo this summer. It's a MkII, post 1965 with the slightly stronger rear fork. For a 51 year old bike it's in remarkably good condition, with most of the original components and just a little surface rust. Plans are to do the following:

1. Strip back to the frame, tidy up the rust, and then respray / powdercoat, decal & lacquer.
   
2. Replace the old steel / chrome rims with new 16"alloys, possibly from a brompton.
   
3. Reuse the old Sturmey Archer 4 speed hub and the front dynamo hub, however both are looking a looking a little tired and will need to be fully rebuilt and regreased. I may be better off replacing the rear hub with something a bit more modern, but also SA.
   
4. Replace the rather ancient original brakes with a modern pair. I have some long reach Shimano R650's from a previous project sitting unused in the shed which look like they may work, although they may cause issues with the mudguards. New cables all round.
   
5. Rechrome the chrome bits (mudguards, chain guard, stem, cranks, chainring, etc)
   
6. Replace the original straight handlebars with drops (not sure about this but do like the look of F Frames with drop handebars)
   
7. If the front dynamo works, then fit a new set of lamps. However I suspect that it doesn't put out enough wattage for decent B&M lights, so may not bother...
   
   

So, the question is - has anyone here restored a moulton? Am I doing this wrong? Should I be a stickler for tradition and keep all the original pieces, or am I right in building a bike that keeps the core of the moulton but uses (some) modern parts?

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I got one myself to do a similar thing but abandoned it due to lack of time but the idea was pretty similar.
I have still got it and will start it at some point.
my idea was to replace all the steel parts for alloy. Chainset, hubs and rims, stem, bars and seatpost.
I had in mind to fit a rear mech and 3 speed block.

If you are going to use it for commuting purposes I would keep the original parts in case you want to bring it back to original spec sometime in the future but fitting some more practical components.

1) I would personally try everything as you would like it first to make sure things fit as it should and repaint eventually. Also not sure how to take the suspension mechanism of the forks apart for repainting.
2) SJS Cycles have a selection of 16" rims. Most 28 holes but 32 & 36 holes also.
4) I cannot remember exactly but I think the drop of the Shimano brakes wasn't enough so I had to get Tektro R559 nutted version. Also there was something with the adjuster that was getting in the way of the end of the seat tube if I remember correctly.
6) I got a Nitto Technomic long quill and I was either going to use Randonneur bars or compact ones plus aero levers.

If you would like to do it on a budget but functional, a Shimano 600 chainset with only the 52T chainring works well paired with a sealed bottom bracket.

Anyway, I will follow this to get some tips for mine.

Thanks.

Yes, I'm definitely going to keep hold of the original bits so it can be brought back to original spec.

Suspension mech is fairly straightforward to disassemble - just need a v long screwdriver to get the front fork separated.

Both hubs look tired, and while they could be restored (and probably will be one day) i think new hubs and wheels are called for.
Brakes however are more tricky. The peculiarities of the rear suspension fork mount mean that the shimanos don't fit, and I reckon the tektros you mention would also struggle. I may have to make do with the originals. I hope the combo of alloy rims and swisstop blocks should bring them reasonably up to date, unless anyone can suggest an alternative.

I like the look of the nitto stem you mentioned.

If that's an old dynohub you should be fine with modern led lights. check your lights have voltage regulation though.

Stripped the main frame and rear suspension, sanded, rust treated and first coat of primer applied. Going to go with the original colour or as close as I can, picked up a tin of metallic Rover racing green from Halfords which looks close and seems vaguely appropriate given moulton's links with BMC.

Lots still to do, rear hub utterly knackered upon further investigation, and front fork remains untouched as I don't have a foot long cross head screw driver.

Anyway onwards...

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I know its only primer, but mustard yellow is an excellent colour!

haha, I was thinking that too. It has a touch of the desert storm about it, but no, metallic racing green it has to be.

perhaps mustard yellow is a little tokyo bike anyway... regardless, looking forward to seeing this build!

Oh excellent! I've got one of these that needs pulling apart and cleaning up. They are so much fun to ride too

Completed painting, rebuilt front and rear suspension, including fabricating a new aluminium suspension contact plate from an old piece of an italian boiler given to me by the excellent chaps at Clever Mike.

Front suspension on a moulton is a thing of beauty - very simple clever design, and given the age of the bike was in excellent condition, both springs and rubber have plenty of life in them.

The halfords rattlecan paint job looks pretty good, and a quick decal from ebay and it's almost good as new.

Debating what to do about mudguards. I have the original but they're rusted and the chrome has gone. I could either get them re chromed, or take them to Armourtex and have them powdercoated (i think white, to match the racks)

Also - front wheel. I have the original SA dynohub, which I serviced and spins well, but it weighs a lot (1.5kg), and is a 50 year old dynamo, so not the best... Should I rebuild with that, or buy a new plain hub?

Anyway, onwards...

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Dynohubs are pretty decent - reliable, as much power output as a modern hub - but a little heavy and a bit of a bitch to build (mainly because of the keyhole flanges on the small-flange side). Worth re-using. Also, Moultons rule all.

Sub'd

👌

The more I think about this the more I think it should have a belt drive. Has anyone any advice on fitting one? Who in London supplies such a thing? Would the rear suspension mechanism cause tension problems?

Excellent project. This looks lovely. Have worked on 3 myself (Mk2 and Mk3 x2). The R559 will have enough reach on the front. Don't know about the back. Fixed gear and duomatic (coaster brake) on two of mine. I've read of others who have changed brakes having issues with the rear brake fouling the rear suspension block, however I do not know the details as I've adopted different solutions (fixed etc).

Belt drive is a really interesting idea. I have noted that when seated the move in suspension will create more tension. Also as the suspension moves over rough ground (poor pedaling style etc) it will affect and change tension. It has not proved a problem on my fixed gear Mk3 however I understand that belt drives need rather precise tensioning.

Definitely worth changing the rims from the steel originals to modern aluminium. Much lighter and way better stopping power in the wet. The Sun rims on SJS are a pig to get tyres on and off and I would avoid them (seriously avoid the Sun rims). Brompton rims are good and can be picked up a decent price.

Would the rear suspension mechanism cause tension problems?

Since the hinge for the rear suspension is not at the bottom bracket... most certainly.

Been meaning to update this for a while. Finished the build a couple of weeks ago and been happily commuting into town since. It's a wonderful thing to ride. not quite as fast as my old Cannondale T800 (which wasn't exactly quick either) but hugely fun, very comfortable and insanely practical. The twin racks make lugging kids stuff to school in the mornings a doddle.

So final specs:

Frame : 1963/64 Mk1 Moulton F Frame
Wheels:
Rear - Brompton rim on Sturmery Archer 3 speed SRF3 hub
Front - Brompton rim on Ambrosio Zenith Endurance hub.
Crankset: Shimano 600 Arabesque 52t
Saddle: Brooks B17
Cockpit : Nitto Technomic stem and Randonneur bars (as suggested by @ElGato)
Brake Levers: Shimano BLZ304
Gear Shifter: Sturmey Archer SLS30 bar end thumbshifter

Everything else was on the bike. Couldn't face getting the mudguards rechromed (cheapest quote was £218!!!!) so they got a dose of metallic silver spray paint. Paint was courtesy of Halfords and the Moulton Club for the decals.

Very pleased with how it turned out and couldn't recommend enough an old Moulton F Frame as a town bike. My only concern is that the gearing (at 52:16) remains a little low. Going to swap the rear sprocket for 14 or maybe even 12 in advance of having a crack at the Dunwich Dynamo this summer on it.

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The bike looks great. How's the suspension on the roads? Does it actually smooth out the ride a little. Oh, and how's the flex when/if you get out the saddle.

But, seeing yours, I really like to have a go at one too! Well done!

Thanks!
The suspension actually works really well. It definitely improves the ride and goes some way to compensate for the stiffness of the small wheels. The frame is incredibly stiff and there is very little flex, however the suspension can make things a bit bouncy if you get out of the saddle.

I suppose if you wanted to be scientific about it you could replace the rubber springs in each side with a slightly harder formulation but I have no idea where you would find such a thing. Moulton don't make parts for 50 year old bikes, and it's not exactly the kind of thing you could fabricate yourself.

You might be able to stiffen the suspension by strapping a jubilee clip around the rubber block. Tightening the jubilee clip would vary the stiffness of the suspension. I have never worked on a Moulton but I know that works on Bromptons.

Unlike the Brompton the Moulton's rubber block is glued in place and is essentially a wedge shape, as in this pic:

https://lfgss.microcosm.app/api/v1/files/209d977eee824805c7d9852694d75732437cd3c3.JPG

There's no way you could put a jubilee clip around it. TBH I like the suspension as it is, which is just as well...

Looking excellent.
It's described here how to stiffen the front suspension should you wish to try it:
http://www.bicyclehub.co.uk/index.php?option=com_content&view=article&id=52&Itemid=114

that looks really good! I'm planning a Moulton build in the not too distant future, I'm on the look out for a standard as I mistakenly bought a mini (14" wheels) in haste!
Cheers,
Matt

That looks brilliant, and a very quick turnaround.
I shall have a go at mine this spring.

Favourite forum bike.