Moulton Mini for distance riding, Advice Required.

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landsurfer
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Moulton Mini for distance riding, Advice Required.

Post by landsurfer »

I have a Moulton Mini, F type frame .. i think .. see picture.
It's currently for sale .. but .. can the frame be converted into a small wheel distance bike ... are tyres available for the 14 inch wheels etc
Can bigger wheels be fitted .... or should i just sell it and get the bigger wheeled version ?

s-l1600-7.jpg
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Brucey
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Re: Moulton Mini for distance riding, Advice Required.

Post by Brucey »

IIRC the required tyres for a moulton mini are 37-298 size (14 x 1-3/8"), as opposed to the standard moulton 37-349 size (16 x 1-3/8" same as is used on Bromptons).

These tyres (also used on the front wheel of original bickertons) are basically obsolete. SJS have a few (not very good) ones and that is about it, apart from a few NOS tyres that might crop up.

This makes a moulton mini a less useful proposition than you might expect it to be, if you plan to actually ride it. The frame won't accept larger diameter wheels and other 14" fitments require different rims and even then they are probably going to be too wide.

I would suggest that you get a standard moulton with 16" wheels if you want that authentic 1960's small-wheeler experience. Even then there are parts for those which are difficult to source.

[edit; you may already have a standard moulton with 16" wheels; the 'mini' is a perfect 7/8 scale model, so it is difficult to tell from the general look of the thing in a photograph, but all the 'Mini' ones I have seen have the seat binder at the front of the seat tube not the back, and have so-called 'clapperbox' rear suspension. Yours looks like a MkII frame (or at least has a MkII straight swingarm) fitted with Mk1 forks. This may have been original since not all changes were introduced at the same time. This one
Image
is a dead ringer for yours, with the same fork and same swingarm, I think ]

cheers

Brucey
Last edited by Brucey on 30 Oct 2018, 6:58pm, edited 2 times in total.
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landsurfer
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Re: Moulton Mini for distance riding, Advice Required.

Post by landsurfer »

The other route is the Raleigh Twenty ... especially the French upgrade variants .. i suppose...
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Brucey
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Re: Moulton Mini for distance riding, Advice Required.

Post by Brucey »

this is a moulton mini back end

Image
clapperbox suspension

you will note that the rack mounts are brazed in position on the 'mini' whereas the standard moulton racks unbolt. Looking at it, it appears that someone has taken a hacksaw to your spine and shortened it by about 4" too.

If you measure a 16" rim it measures about 14" because the BSD is 349mm and the 16" size refers to the rolling diameter of the complete wheel, i.e. with tyre.

Image

cheers
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landsurfer
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Re: Moulton Mini for distance riding, Advice Required.

Post by landsurfer »

In the mean time i have purchased a Raleigh Twenty .. recently there was a link to a French language upgrade page for he Raleigh Twenty ... could someone re-post the link please ...
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speedsixdave
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Re: Moulton Mini for distance riding, Advice Required.

Post by speedsixdave »

I don't think Minis ever had the front rack mounts. However checking the tyre size on the side of the tyre should answer your question.

Assuming it is 16x1 3/8 / 349, there are plenty of fairly decent tyres available but the straightforward choice is between Schwalbe Marathons for utility riding and touring, or Kojaks for going a bit faster.

Moultons make an admirable bike for distance riding, and there are numerous accounts ancient and modern of folk having used them for just that. Series 1&2 F-frames have an extremely cultured ride which, assuming your riding style is sympathetic, is a joy. They are not without idiosyncrasies however. Things that are worth thinking about include:

(1) age. Your bike is over fifty years old and may thank you for a good inspection and overhaul. Rear pivot bolts can seize. Front suspension nylon bearings may be worn. On Series 1 frames the bottom bracket area can develop cracks. Very occasionally front forks can fail, which is clearly a potential danger. It is thought that these are all from one bad batch, and there are ways of telling whether you have these.

(2) weight. If you judge the quality of a bike by how little it weighs, you are likely to be disappointed.

(3) wheel size. Obvious, but small wheels and big potholes do not mix well. Be wary riding in the dark.
Big wheels good, small wheels better.
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Brucey
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Re: Moulton Mini for distance riding, Advice Required.

Post by Brucey »

you can have a lot of fun with modernising either a Moulton or a Raleigh twenty and turning it into 'something else' but there are multiple problems with Raleigh twenties that require some proper engineering to sort out. Maybe this is the sort of challenge that you like...? By contrast you can buy most of the bits to sort a moulton out and they just bolt on. The moulton bike in your pictures looks as rough as hell but it is (with the exception of the shortened spine) all sort-out-able using little more than spanners and an electric drill.

With a Raleigh twenty you will probably need to

- sort the headset out (as is it will have a crappy plastic bush in the top instead of ball bearings)
- revise the bottom bracket; the shell is 78mm wide and is tapped 26tpi.
- modify the front dropouts (so that a standard hub will fit)
- build decent wheels (and there is a whole speil about rim sizes, tyre sizes, tyre choice, stupidly low bottom bracket heights (if you use 406 rims with skinny tyres), brakes that don't reach etc etc)
- sort the brakes out (easy or difficult depending on wheel size used)

A series moulton is not a lightweight bike by any means. But there is no escaping the fact that no matter how many nice light parts you throw at it, the Raleigh twenty frameset is something of an unyielding boat anchor. If you look on the internet you can find hordes of 'interesting' modified R20s and Dawes kingpins etc and they are likely to be pretty nasty to ride on any kind of imperfectly smooth road.... There is a reason Dr Moulton used suspension when he designed a bike with small wheels.... :wink:

One thing that works in your favour with a series moulton is that the 349 (16 x 1-3/8") rims and tyres are readily available and will remain so as long as they make Bromptons. By contrast the 'correct' 451 size rims and tyres for a Raleigh twenty are less easy to obtain, and may in time go extinct.

cheers
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Ugly
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Re: Moulton Mini for distance riding, Advice Required.

Post by Ugly »

WP_20160704_12_53_39_Pro.jpg
WP_20161110_13_23_53_Pro.jpg


This is my 1965 Moulton Automatic, I paid #25 at the Benson Rally. The renovation comprised Powder coat, new alloy rims, tyres & tubes, Bottom Bracket, chain and sprocket, SPD pedals, long seat post and saddle, brake blocks and cable.
Transmission is through a duomatic 2 speed hub with coaster brake, ratios are c65" and c50". It is a very pleasant but slow ride. I have done a number of 60 mile rides on it. Plans are afoot to equip it with drop bars and alloy bits.
Brucey
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Re: Moulton Mini for distance riding, Advice Required.

Post by Brucey »

good work fella!

one note of caution is that you have the series 1 swingarm there. These quite often start to crack if you have a high load/lots of miles. There are folk who repair/reinforce them when the need arises.

Another issue that can happen is that the main spar starts to crack near the swingarm pivot, leading eventually to this;

Image

I have repaired several moultons which were cracked in this area. Basically the cracks are welded up and then near the pivot a second skin is added to the first, effectively doubling up on the wall thickness, and therefore halving the service stresses. This is hardly visible once it is done and none of the repairs have yet failed, so I think it is a good scheme. However if problem is caught late and the bike actually breaks, getting everything lined up correctly afterwards is extremely problematic.

cheers
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speedsixdave
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Re: Moulton Mini for distance riding, Advice Required.

Post by speedsixdave »

Brucey wrote:good work fella!

one note of caution is that you have the series 1 swingarm there. These quite often start to crack if you have a high load/lots of miles. There are folk who repair/reinforce them when the need arises.


As you note Brucey, Series 1 rear forks were underbuilt and sometimes cracked, hence the less elegant but stronger Series 2 rear fork. Moulton Automatics were a bit of a mongrel and seem to have been actively designed to use up excess parts. They were fitted with Series 1 rear forks long after other Moultons went to Series 2, but the cracking problem was acknowledged by then and all Automatic forks that I have seen have an additional bracing plate brazed in place. The common consensus is that these adapted Series 1 rear forks do not crack. But there's always an exception!
Big wheels good, small wheels better.
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Ugly
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Re: Moulton Mini for distance riding, Advice Required.

Post by Ugly »

Speaking to Tony Hadland on a VCC ride he said that the Automatic and the Continental were built using up bits and bobs. Mine seem to be the reinforced version. Many years ago I bent a Moulton swinging arm. Riding back from the pub with my traditional built partner sitting on the carrier carrying the fish suppers! Must have been the suppers that did the damage.
cycle tramp
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Re: Moulton Mini for distance riding, Advice Required.

Post by cycle tramp »

landsurfer wrote:In the mean time i have purchased a Raleigh Twenty .. recently there was a link to a French language upgrade page for he Raleigh Twenty ... could someone re-post the link please ...


Cool! Looking forward to seeing the finished bike (sometimes i wonder about organising a short run of nee raleigh twenty frames to be built with proper bottom brackets, modern drop out widths, derailleur, disc brake & hub brake mounts)
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landsurfer
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Re: Moulton Mini for distance riding, Advice Required.

Post by landsurfer »

And a link to the french Raleigh Twenty upgrade page ???? i had it but cannot find it again ...help
“Quiet, calm deliberation disentangles every knot.”
Be more Mike.
The road goes on forever.
Brucey
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Re: Moulton Mini for distance riding, Advice Required.

Post by Brucey »

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kylecycler
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Re: Moulton Mini for distance riding, Advice Required.

Post by kylecycler »

Here's the Google translation, landsurfer. Not perfect, it never is, but enough to understand it si vous ne parlez pas français. :)

https://translate.google.co.uk/translat ... t=&act=url
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