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Old 10-24-18, 03:18 PM
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How did you manage to fit the triple derailleur? I tried it on my Dahon, but it didn't fit. I don't remember what the problem was but I think the swing mechanism was thicker or the swing starts further in, causing interference from the seat tube or making the derailleur start further out when compared to the double.

I ended up putting on a double. I also had to bend the plates to get them wider. I used the Litepro P adapter but the bracket was designed poorly and wouldn't fit any of the derailleurs I tried, so I 3D printed my own out of stainless steel bronze, with the clamp mounted from above. I used 2 clamps, one lower with a cable stop. The stainless steel bronze was almost 150-200g, because I made them very thick since the material tends to be brittle. Aluminum is stronger and could be half the thickness at 40-50g, but costs twice as much to print.

I have a 26/46 and I found 20t jump to be the limit, with 8mm chainring spacing. If I spaced it wider, it won't shift. If I space it closer, the chain while on the inner ring will rub on the outer ring when trying to go higher than 6th gear. With 8mm spacing I can run it up to 7th gear. I used 8mm and 10mm DIN 988 shim washers, 0.2mm thickness, to adjust the spacing, you can buy a 100 pack for $3 on ebay. It needed a chain catcher, without one the chain would drop once every couple days.

Last edited by tomtomtom123; 10-24-18 at 03:22 PM.
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