Alan asked several questions about QB/SO gearing: "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?"
This is one of the ways people might set up their bike " How close do the chainrings and cogs need to be to avoid having to change the chain length?" It depends. The slots on the Quickbeam and the Simple one are long and are slanted such that you have a lot of gearing spread latitude and you hopefully won't have to adjust brakes for a gear change. Since you are not using those Quickbeam dropouts, you might have a different amount of capacity, and almost certainly will need to adjust your brakes for every gear change. Some people go strictly fixed in the rear and don't use a rear brake to enable gear changes with a dingle. "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?" Yes you can. Modern chains are super flexible, and laser straight chainline is not critical "Will it work with a standard track dropout or was there something unique on the simple one/quickbeam?" The Quickbeam dropout was long and slanted. Standard track dropouts are flat. A wheel position change requires a brake pad adjustment, almost always "Can someone give me examples of the gearing they use?" I use 35/38 tooth chainrings in front with a White Industries 16/19 freewheel in back. I use two gears: 35x19 and 38x16. The wheel position is the same for both gears, so I don't have to adjust brakes with a gear change "What double crank works or do I have to make a custom one?" If by 'make a custom one' you mean buy arms and pick your two chainrings, then yeah, you will probably make a custom one. I used a 110BCD Campy square taper crankset when they were being dumped for practically free. "My frame was originally built with a 120 rear but I respaced it to 126...will that work?" It depends. I don't know of a 126mm flip flop hub. "Are flip flop wheels available with quick release, and is it OK for fixed gear riding?" If you can find a 126mm flip flop hub, then I imagine you could at worst do an axle swap to make it QR if you need to. Phil Wood does custom configurations, so you can get anything you are willing to pay for. "I'm wondering how often I would change the gears if I needed a wrench for the axle nut." Using a wrench for gear changes is one of the major benefits on my bike. I loosen only the drive side nut, move the chain to the other gear, and then tighten that one nut. The non-drive-side nut holds the wheel in position while I'm doing it. My hub is a Phil with 6mm allen axle nuts. My tool kit is a nice long 6mm allen key and a plastic tire lever. I use the tire lever to move the chain over, so I don't get dirty fingers. My 35x19 is my uphill gear, and my 38x16 is my everything else gear. BL in EC 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 [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/rbw-owners-bunch. For more options, visit https://groups.google.com/d/optout.
