Can it be simpler than this? (Brompton)
#1
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From: Newcastle upon Tyne, England
Bikes: Brompton H3L, RAF, M3L, Dahon, Giant NRS, GT
Can it be simpler than this? (Brompton)
A 2 speeds fully functional brommie.


Last edited by bike.gang.uk; 07-21-14 at 09:01 AM.
#7
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From: Newcastle upon Tyne, England
Bikes: Brompton H3L, RAF, M3L, Dahon, Giant NRS, GT
You spot it! coaster brake to remove the brake lever, cables, brake pad ...
Last edited by bike.gang.uk; 07-21-14 at 09:15 AM.
#8
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Brake delay as the chain tensioner moves up ?
I note: didnt take out, links [half link] to push it up to be tensioned on the bottom ,
and so the spring only kicks in winding the tensioner when you fold it..
You are obviously a flatlander .. in Tyneside.
Weight in the front bag makes the low trail handling better .. But to each their own... YMMV.
I note: didnt take out, links [half link] to push it up to be tensioned on the bottom ,
and so the spring only kicks in winding the tensioner when you fold it..
You are obviously a flatlander .. in Tyneside.
Weight in the front bag makes the low trail handling better .. But to each their own... YMMV.
Last edited by fietsbob; 07-21-14 at 10:08 AM.
#9
Simpler? You mean how you have to plan your crank position for folding and your stopping since there's no front brake(70% of your braking gone)?
I would have forgone the coaster and lived with ugly brakes.
I would have forgone the coaster and lived with ugly brakes.
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C'dale BBU('05 and '09)/Super Six/Hooligan8and 3,Kona Dew Deluxe,Novara Buzz/Safari,Surly Big Dummy,Marin Pt Reyes,Giant Defy 1,Schwinn DBX SuperSport,Brompton S6L/S2E-X/M6L-X/S12 T Line


C'dale BBU('05 and '09)/Super Six/Hooligan8and 3,Kona Dew Deluxe,Novara Buzz/Safari,Surly Big Dummy,Marin Pt Reyes,Giant Defy 1,Schwinn DBX SuperSport,Brompton S6L/S2E-X/M6L-X/S12 T Line

#10
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Greenspeed , Australian Brompton importing-distributor
Re Machined a Sturmey Archer Drum brake to fit in the 74mm Fork
to cleverly add a front brake back on.
Re Machined a Sturmey Archer Drum brake to fit in the 74mm Fork
to cleverly add a front brake back on.
Last edited by fietsbob; 07-21-14 at 10:34 PM.
#11
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From: Newcastle upon Tyne, England
Bikes: Brompton H3L, RAF, M3L, Dahon, Giant NRS, GT
I believe they used https://www.sram.com/sram/urban/products/automatix
And you are right, for safety reason, front brake should be there.
Folding is the same, mod the hub to fit the frame.
Moulton has something similar. I wonder how well the belt drive works.
And you are right, for safety reason, front brake should be there.
Folding is the same, mod the hub to fit the frame. Moulton has something similar. I wonder how well the belt drive works.
#12
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belt drive works well
HOWEVER as they are designed for "big" bikes .... the rear sprocket is somewhat big with 20 or more tooth
the front one needs to be SUBSTANCEABLE bigger than the picture above .... and those really big front chaindrives are not available ...
so u have a very cool bike .. but cant go any faster than 10 miles per hour ...( well a little but not much )
HOWEVER as they are designed for "big" bikes .... the rear sprocket is somewhat big with 20 or more tooth
the front one needs to be SUBSTANCEABLE bigger than the picture above .... and those really big front chaindrives are not available ...
so u have a very cool bike .. but cant go any faster than 10 miles per hour ...( well a little but not much )
#13
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From: San Rafael, California
belt drive works well
HOWEVER as they are designed for "big" bikes .... the rear sprocket is somewhat big with 20 or more tooth
the front one needs to be SUBSTANCEABLE bigger than the picture above .... and those really big front chaindrives are not available ...
so u have a very cool bike .. but cant go any faster than 10 miles per hour ...( well a little but not much )
HOWEVER as they are designed for "big" bikes .... the rear sprocket is somewhat big with 20 or more tooth
the front one needs to be SUBSTANCEABLE bigger than the picture above .... and those really big front chaindrives are not available ...
so u have a very cool bike .. but cant go any faster than 10 miles per hour ...( well a little but not much )
#14
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From: Olney Illinois USA
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Don't let pictures mess with the facts .. the TSR-2 belt drive above runs a 67/25 with a g/i of 50 to 68 .. so with a mild cadence of 90 rpm you have a top speed of just over 18 mph .. not bad, spin 100 and you are over 20 mph .. on the shelf I have an 80t and a 100t .. my personal everyday runabout TSR-5 runs an 80/25 for a 37/93 gi ... and so it goes ..
#16
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From: Olney Illinois USA
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:-) I believe you no prob..
that is a gorgeous bike for sure
need to get myself back into that belt drive thingy... and see what can be done on Dahons which makes sense, there is something real magic about the silent drive of a good belt system
that is a gorgeous bike for sure
need to get myself back into that belt drive thingy... and see what can be done on Dahons which makes sense, there is something real magic about the silent drive of a good belt system
#18
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From: Toronto, Ontario, Canada
Bikes: Wheeler Mtn bike, Strida 5.0, Tern Link Uno, FSIR Spin 2.0, Dahon Mu P8
i think that's someone personal broomie and probably gone by now. It's waaay to custom to be something the shop sells.
#19
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That's a 67t
the (disallowed)10 mm pitch track chains , back in the day,
resulted in smaller cog-chainrings with the same, tooth count, gear ratios..
#20
#21
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From: Newcastle upon Tyne
Bikes: Xootr swift, Moulton Speed, Moulton Major.
#22
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From: Newcastle upon Tyne
Bikes: Xootr swift, Moulton Speed, Moulton Major.
have my eye on this vigor p9, looks very nice - Dahon Vigor P9 2014 Custom Lightweight - Detailed item view - www.foldingbike.biz
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