Moulton AM2 upgrade to Alfine 11

[StephenN]

How can I upgrade my Alex Moulton AM2, with it's 17'' 28-hole rims, to run an Alfine Di2 11 speed hub gear SG-S7051-11, which a requires 32-hole rim. Is there a work around? Many thanks.

[simonineaston]

Have you considered asking the good folk at the factory? They will have come across every possible permutation by now, I imagine! Unfortunately, you've plumped for the one option that's the hardest (as you'll already know, obs!), as a move either way to models with 16" or 20" inch wheel rims widen your choices considerably. Experienced wheel builders will outline cunning ways to thread spokes that allow the use of mis-matched numbers of holes at rim & hub, but that would seem a last resort to me. Nice idea, though - I'm very much liking my own TSR / Afline combo.. A further approach, which you must have already considered, is to abandon your preferred AM frame and go with a TSR or SST frame. Folks as has ridden both do say that the difference is not a stark as you'd think, as the TSR frame-set has undergone many small improvements along the way, since it emerged from the Good Doctor's drawing board in the form of the rather clunky, heavy and a tiny bit crude, APB...

[Mick F]

For the CS-RF3 hubs, SA actually list them in 28h, 32h and 36h, but only available in UK in 36h
https://www.sturmey-archer.com/en/produ ... rf3-silver

Chap on here contacted Japan directly, and had a 28h imported. I had the same problem, but as my wheel was a 406 (20") rim, I just bought a 36h rim instead.

Shimano actually offer the Alfine SG-S7051-11 in 28h ....... so ask them.
https://bike.shimano.com/en-EU/product/ ... 51-11.html

[Brucey]

it is also possible to build a 28h rim onto a 32 or 36h hub. However it is something of a PITA to do, requiring many different spoke lengths and some mental anguish.

Edit; also the A11 hub is 135mm OLN and the AM2 is (IIRC) much narrower at the back than that, either 120mm or 126mm I think...?

cheers

[simonineaston]

Shimano actually offer the Alfine SG-S7051-11 in 28h ....... so ask them.

Best bet, I think - yummy

also the A11 hub is 135mm OLN and the AM2 is (IIRC) much narrower at the back than that, either 120mm or 126mm I think...?

I think that's the deal-breaker, though... Go with the TSR/SST frame set.

[StephenN]

Thanks very much to the Wise Men who have responded. Having read your comments and the additional information below, I have decided to pull the plug on the project converting an AM2 to an Alfine 11 hub.

Have no direct knowledge of such a conversion, but can give you some idea
of what problems you might come up against.
1, I am pretty certain that the hub over locknut dimension will be too wide for
the drop out. (Do not attempt to widen the fork as the tubes are very thin
walled and liable to crack).
2, 17” rims are not generally available with 32 holes, you may have to buy a
plain rim and get it drilled to suit.
3, a rear brake calliper should fit onto the mudguard bridge o.k. try your
existing front brake for size.
4, how will you maintain the frame separation, I cannot remember seeing
any cable abutments, new ones will possibly have to be brazed on.
Just a few points to ponder, a narrow 5 or 8 speed Sturmey-Archer might
just be a possible alternative.

[Sid Aluminium]

Or one could convert the Moulton AM from the original 17" (ISO369) wheels to the slightly smaller 18" (ISO355) size, in which 32 hole rims are commonly available (and there's a wider selection of tyres).

Sheldon said a version of the Shimano Nexus 8 could be set up @ 126mm OLD. With thin locknuts the Sturmey-Archer XRF8 is said to skinny down to 116mm and is available in 28 hole.

By all means have cable stops brazed on the Spaceframe and then have it powder coated in a colour that makes cyclists drop to their knees and weep at the beauty of Dr. Moulton's masterpiece - if budget allows. Conversely, Philistines can maintain separability with common cable splitters and Sturmey strap-on cable stops.