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Don't want to name and shame, but my dad's having his Brompton (old model 2005 T6 - 6 speed) serviced and it all seems a bit punchy, but justifiable.
The dude referenced having all the alu bits replaced as they're too old. My dad said no to that.
But he just sent me this:
... have to have new rear wheel as no old style sprockets etc
Surely that's bull shit?
Aren't they just the old style slip on SA sprockets?
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no, hes correct. I imagine its a SACHs/SRAM hub not an SA. so the sprockets stopped being made 10 years ago.
As a cheaper alternative to reuse the SACHS/SRAM hub, could it not be converted to a three-speed set up with the 3-speed socket sets QRSPRSTACK-SA3-13 or QRSPRSTACK-SA3-14, plus a 3-speed tensioner?
[Edit: the 3-speed SACHS/SRAM used different spacers from the SA version, though the sprocket's were the same width.]
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The solution they offered was a new rear wheel gearset and levers.
But then you're into a pretty big spend going with this shop, to the point that a new one, or nearly new 2nd hand is probably better.
From reading this thread on and off, I do realise Brompton stuff is often pricy and has a load of random maintenance stuff that you often don't know about. Hence why I didn't want to rip into a LBS for what all may be by the book stuff.
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Ah, the problem is that there’s no 3 lug cogs with shifting ramps right?
There seems to be folk making it work with standard cogs (some reports of having to grind a little thickness off the base of the cogs to get them to fit) and when you think about it, people rode (a lot more than 2) gears for years and years before shifting ramps came about.
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I had this only last week with a customer. The 6 speed Sachs hub used 1/8th width sprockets with 3 splines, and these haven’t been made for ages now. SA 2 and 6 speed hubs use 3/32th width sprockets with 9 splines, which are freely available. We managed to find a supply of larger 1/8th sprockets a while back, but they’re only the larger ones, 15 and 16t. A Brommie needs 13 or 14t too, and they’re just not available.
SRAM bought Sachs out and stopped production some years back. Brompton only briefly used the Sachs hub when SA went belly up about 15 or so years ago, until SunRace bought SA and started producing the hubs again after a two-year break.
So in short the shop is calling it straight. It’s not Brompton’s fault, but SRAM. The only way is to replace the rear wheel, I’m afraid.
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Cheers for the history lesson. That's really interesting.
It's a pain, but as he doesn't use it much it's not that big a deal. Just a shame that the service can't include a new chain and sprockets.
Still he having marathons fitted so that's probably worth the cost of the service alone.
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https://www.condorcycles.com/products/sturmey-archer-1-8-3-spline-flat-sprocket shows a 13t 1/8” sprocket in stock.
https://www.sjscycles.co.uk/sprockets/sturmey-archer-13t-sprocket-18-flat-hsl854/ similarly.
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Just a shame that the service can't include a new chain and sprockets.
A 3-speed conversion to use a new chain and sprocket still seems feasible. Checking the parts list for the SA replacement 3-speed sprocket kit against the old SRAM/SACHs one shows that they both take the same three-spline 3mm width sprocket. So, if you could get a secondhand set of the spoke guard and two 2.2mm spacers from a discarded SACHS 3-speed set up, you should be able to use a new SA sprocket with those parts.
SRAM/SACHS sprocket parts diagram for QRSPRSTACK-SR3-13:
https://issuu.com/bromptonbicycle/docs/qrsprstack-sr3-13-14_asand SA parts diagram for QRSPRSTACK-SA3-13:
https://issuu.com/bromptonbicycle/docs/qrsprstack-sa-13-14_as -
1/8th width sprockets with 3 splines, and these haven’t been made for ages now.
I beg to differ.
https://www.sjscycles.co.uk/sprockets/brompton-sprocket-13t-r-3-mm-3-spd-for-1-18-inch-chain-iso/
https://www.sjscycles.co.uk/sprockets/sturmey-archer-24t-sprocket-18-dished-cp-hsl876/
https://www.amazon.co.uk/Sturmey-Archer-14t-coaster-brake-cog/dp/B003RLE95G
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https://www.condorcycles.com/products/sturmey-archer-1-8-3-spline-flat-sprocket shows a 13t 1/8” sprocket in stock.
https://www.sjscycles.co.uk/sprockets/sturmey-archer-13t-sprocket-18-flat-hsl854/ similarly.
Yes but for the 6-speed SRAM/SACHS set up, the width of the outer sprocket by the hub needs to be 3mm with the teeth narrowed down to take the 3/32" chain. Here is the parts diagram with dimentions for QRSPRSTACK-SR6:
https://issuu.com/bromptonbicycle/docs/qrsprstack-sr6_as -
A Brommie needs 13 or 14t too, and they’re just not available.
Condor found them,
SJS found them,
https://www.sjscycles.co.uk/sprockets/sturmey-archer-13t-sprocket-18-flat-hsl854/
This seller on eBay found them,
So did this one,
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It's a business opportunity, I was looking at this a while back and yeah still thinking of making this work!
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1/8"...
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We’re a shop. None of our suppliers have them.
This may be true but it's very different from they ain't made.
Nor do SJS - I know, we asked them.
They are currently showing in stock.
Sure a few ebayers may have some NOS hidden away but that’s all.
I'm sorry but I refuse to beleive that what must be the most prolifically and cheaply available sproclket standard is all coming from NOS.
Sturmey currently have at least 19 models of hub on this page that take that size of 3 spline sprocket, you're telling me they are offering that many hubs but just don't make 1/8" cogs to support them?
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1/8"...
I was replying to @jj72 who had said,
"The 6 speed Sachs hub used 1/8th width sprockets with 3 splines, and these haven’t been made for ages now. SA 2 and 6 speed hubs use 3/32th width sprockets with 9 splines, which are freely available. We managed to find a supply of larger 1/8th sprockets a while back, but they’re only the larger ones, 15 and 16t. A Brommie needs 13 or 14t too, and they’re just not available."
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@worrywort
yes, anything pre 2002 is IGH only got 2 less pristine triangles if anyone requires