Sammyboy

Ok, many of you will remember that I have a couple of Moulton Minis, one of which has had the back carrier snapped off. I plan to make this one into as fast a road bike as I can. I know this is a stupid idea, but I'm going to do it anyway. I just want to see if I can hang with group rides I happen upon on a bike which originally had 14" wheels and is so tiny.

In previous threads, it's been suggested that 305 wheels will fit, and that an SA8 speed would be the easiest hub solution both from the gearing and OLN point of view. An SA8, however, only takes a minimum 19t cog, which might cause clearance issues (I guess that I could test this with my DT Mini wheels), and also, I've had no luck trying to find one at less than about £130. In the same period, I could've bought a number of Nexus 7 speed hubs for around £50, and Nexus 8s for less than 100 (sometimes a whole bike with a Nexus 8 for £70). The Nexus also has a better rep than the SA, though I've had no trouble with the SA on my Mini.

Now I've got a 61t chainring on it's way to me, and I've actually got my eye on a 69t motorpace track chainring on eBay, which would allow me to run the Nexus hubs (or indeed an SRAM 7 or iMotion 9, if I could find one for cheap!). What I'm wondering is whether anyone knows whether spreading the rear triangle is likely to create more problems, or if it's probably a better solution than the SA8? What I should really do is haul the bike out and try the DT Mini wheels in it, I suppose.

joose

My mind melts just trying to understand your question..!

Can't you ask easy ones like what colour should i get etc lol

Sammyboy

I'm kinda shooting in the dark with this one, cos there's not many old Moultons on this board, still less Minis, and still less people who have extensively modded Minis, but hey, it's worth a try! I get bored with the "should I buy a Dahon or a Downtube?" threads!

stevegor

Sammyboy,

The SA hub has a 124mm over locknut dimension, (O.L.D.), with a possibility of reducing that to 115mm if you remove one locknut, so very little if any cold setting of the frame would be required. The Shimano Nexus 8 has an OLD of 132mm, so careful cold setting should be possible with the frame, probably the same with the iMotion 9. If you go for the Nexus 8 get the red band model as it is lighter in weight and uses better quality bearings etc.

Check out Sheldon Brown's site for more info on cold setting a frame if you're unsure.

Sammyboy

My concern is not with coldsetting per se, but with coldsetting a frame with such short stays. There's just some part of me that says it would be harder. I won't employ any of the "scaffolding pole" type methods; instead, I'll buy a threaded rod of the right diameter, and do it with nuts inside the dropouts - I'm way to clumsy to get it right with a long lever.

what bike?

sammy search around for people who have modded old moultons see what components they have used.

Sammyboy

Yeah......trouble is, you won't find anyone who's modded a Moulton Mini. They had 3/4 size frames, and 14" wheels. I believe I'm the only one here to try it.

Lalato

I approve of trying the DT Mini wheels first. It should give you a good idea of where to go from there. As always, it doesn't matter what you do unless you provide pics of the process for us... the hungry masses.

--sam

Sammyboy

Hahahaha, ok, fine. On Saturday I'm planning to haul my Raleigh 20 out for stripdown (I'm determined to finish the wheels this weekend. The front is due for it's second complete stripdown due to my slow learning!). Whilst I'm in the garage, I'll drag out the Moulton and try the Downtube wheels (I assume I can get skinnier tyres if that will help). Photos will be forthcoming. In the meantime, here is the bike in its raw form:



It'll get cotterless cranks (with either a 61 or 69t chainwheel, depending on a number of variables) drop bars, longer seatpost and a Brooks saddle, new wheels with IGH, decent dual pivot brakes, and that's yet lot!

SesameCrunch

Maybe it's hard to see from the picture because the drivetrain is on the other side, but what would cause a clearance problem for a 19t cog? I don't see anything...

I put a 23t SA8 on my MK3, with the triangle frame and all, and there was no clearance problem.

Also, Stevegor is right about being able to reduce the OLD of the SA8 hub to 115mm, but you need a thinner axle nut to replace one of the existing ones.

Sammyboy

I don't know, but I'm very aware that this is an issue for Bromptons, and wondered if it might be the same situation. I'd be very pleased to be able to use a Nexus 8 instead of an SA8, but ultimately, it will probably depend on what I manage to find inexpensively!

I also wonder if the spoke count might be an issue.

SesameCrunch

No comparison between the complexity of the Brompton rear-end versus the Moulton. The Brompton has all kinds of considerations that preclude any changes (mostly because of the folding design). The Moulton has no similar constraints.

Methinks you can sleep easy on this one....

what bike?

take off the remainder of the rack at the back it would look better

Sammyboy

There is no remainder of the rack; those stays are structural to the seat tube.

maranen

You are awfully lucky Sammyboy – you have a full suspension bike. I’m trying to do this (“to make this one into as fast a road bike as I can”) with my Mercton - Daigoro. I just received a new suspension block from Rapiddescentscotlanc yesterday and fitted it – I must say it is better than the rubber block with which I experimented. I’m still wondering should I try to switch the front wheel (& fork) to take a 355 Schwalbe BigApple tyre – to operate as a front suspension – or should I give up and buy a Birdy. For me the folding bike is a must – even though I wanted Evelv’s Moulton so badly. BTW have you seen this https://reviews.mtbr.com/blog/category/press-and-news/ (check out the video, it’s awesome) - may be a competitor to the Schlump – may be something to do with folding bikes in the future.

griftereck

I bid on that 69 tooth ring
got out bid...boo hoo

was going onto my new project bike that has 16" 305 wheels

I had a moulton mini.
Ran it on stock single speed.
reved out everywhere.
was good

Sammyboy

Wow, that went through the roof! When I found the 69t ring this morning, it was on £1. I'm less likely to buy it at the current price.....

stevegor

The SA 8 hub does get some bad reviews, however according to Sheldon's info, the "inferior" hubs were the ones made in England, the newer hubs were made in Asia when the factory was tranferred there and are of much better quality. I purchased both of mine from Harris Cyclery in the US, so I'm supposing they supplied the better ones? So far I've had no problems with mine and I do work it quite hard, maybe Jur just had bad luck with his ...or he's a super human hub breaking machine.

I would check with your rim supplier to see if you can get rims with 36h for the size you need, I think SA, Nexus 8 and Sram iMotion 9 hubs come with 36h.

IMHO, the SA would be less hassle to fit and it's cheaper, but we all dream of using a Nexus, Sram or even a Rohloff as the ultimate IGH for our folder bikes.

jur

My SA8 hub problems strictly speaking are the planet gear breakage and the 6th gear over-sensitivity. It is too easily out of 6th gear, the adjustment has to be blooming perfect and even then with a small amount of dirt it will start acting up. This is a known problem - Sunrace has reportedly fixed this sensitivity issue in the new release. The broken gear problem has been experienced by others too. I know specifically of one other and anecdotally of more.

I also think it is not great for riding in wet conditions - the big diameter seal next to the driver seems to let water in too easily. Steve you have also reported on yours making noise after some wet riding - that is grit rubbing in that seal.

I got mine from aebike, their prices were the best and guarantee service was perfect too.

SesameCrunch

Sammy:

The SA8 is available for $160 here: https://cgi.ebay.com/Sturmey-Archer-8...em320207697983

Just thought you'd want to know.....

Sammyboy

I've got an SA8 on my Downtube Mini, and it gives me zero problems. I had to change the cable, and found it easy to set back up, it has never missed a shift, even in 6th; generally, I like it. The consensus, however, is that multi speed hubs are most efficient in their direct drive gear. With the SA8, that's first, which I only use in one place on any ride I ever use it for. I don't mind making that compromise when it's the only thing which will do the job, and in the absence of chainrings bigger than 52t, it IS the only thing, for a 305 wheel bike. However, if I'm going to have access to a 61t ring, then a 14t cog on the Nexus 8 gets me a top end of 94.7 gear inches, which is French for "enough", and a 69 t cog would give me a really big top gear. What's the smallest cog one can use on a Nexus hub? I'd like to have the direct drive gear somewhere in the middle, if I could.

Oh! The SA8 is also available in 28h (it's that drilling on the Mini, and I actually know an online retailer who carries them in that drilling). I don't know about the Nexus. That's a great price for the SA8 - the cheapest I've seen it for is £125 ($250 after exchange rates!) and that's without a shifter! I've mailed the seller to ask him what he would charge for UK shipping. The other downside, of course, is that it's a 36h drilling, not 28.............

jur

I think there might be 13T ones around.

Sammyboy

I've just found a source for 36h 305 rims. The world is, once more, my lobster.

SesameCrunch

Lucky you!

If you lust after the cheaper hub on ebay, I'll be happy to receive it here and then bring it over for you when I come for my Excellent Adventure.

Sammyboy

Not sure I can afford it that soon. Or to put it another way, sure I can't afford it that soon! I think I'll go a-huntin' for a Nexus 8, since with your chainring, I can definitely use it. I already have an SA8 - time for something new?