I've run my Quickbeam and another singelspeed with fixed Dingle cogs for many years, but they're both set up as single-gear fixed now. I will put my Quickbeam back into dingle mode soon - I switched cranks to an old Shimano 600, and it sits too close to the BB shell to allow an inner ring. The QB came with 40/32 rings and an 18t freewheel. The long track end allows for that 8 tooth spread. I don't recall having an issue with the brake shoes, but I wouldn't rule it out. I used the stock rings with a 15t fixed cog, and then with a 17/21 Surly dingle cog. Most recently I used a 39/44 road double with the 17/21. I simply replaced the 52 tooth ring from a normal road double.
I like the two gears to be on the same side of the bike, because gear changes then are literally a 15 second affair. I really like quick releases for fixed gears. The lock the wheel better, and you never forget your tool. Dingle setups with quick releases are easy: Loosen the QR, slide the wheel forward to slacken the chain, lightly clamp the QR, and derail the chain onto the new gear. Roll the bike forward to get the chain around both the cog and the ring, then slide the wheel back to tighten the chain, clamp the QR for real, and ride away. Crossover gears are probably fine with a nine speed chain, but I don't recall ever doing that. The chain length is more of an issue there. You might not have the dropout length to accommodate the change in axle position. e.g.: 44+17=61, and 39+21=60 so one tooth difference is about 1/4" of axle movement backwards. 44+21=65, so 4 teeth difference is 1" of movement forwards. So even if you have a 1 1/4" dropout length, your favorite gear might not put the axle at the right spot to use the whole thing. Here's my old write-up about how another list member geared his Quickbeam: http://www.biketinker.com/2010/bike-resources/multi-speed-fixed-quickbeam/ Philip www.biketinker.com On Tuesday, June 6, 2017 at 7:50:07 AM UTC-7, alan lavine wrote: > > Hi All, > The simple one for sale got me to thinking about doing something similar > with a fixie frame I made at United Bicycle Institute a few years ago. > IIRC you can put 2 closely spaced chainrings up front. Then in the rear > with flip flop hub, you can use a double freewheel on one side and even a > double fixed cog on the other. Is this right? How close do the chainrings > and cogs need to be to avoid having to change the chain length? Can you > use a "crossover" gear, i.e. one chainring with either of the cogs in the > rear (FW or fixed), or do they need to be in the same plane? Will it work > with a standard track dropout or was there something unique on the simple > one/quickbeam? > > Can someone give me examples of the gearing they use? What double crank > works or do I have to make a custom one? My frame was originally built > with a 120 rear but I respaced it to 126...will that work? Are flip flop > wheels available with quick release, and is it OK for fixed gear riding? > I'm wondering how often I would change the gears if I needed a wrench for > the axle nut. > > Lots of questions, sorry, but I'm thinking it would make an interesting > project. > > Thanks in advance, > Alan > NYC > -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To unsubscribe from this group and stop receiving emails from it, send an email to rbw-owners-bunch+unsubscr...@googlegroups.com. To post to this group, send email to rbw-owners-bunch@googlegroups.com. Visit this group at https://groups.google.com/group/rbw-owners-bunch. For more options, visit https://groups.google.com/d/optout.
