Looking for a 20" fixed gear rear wheel
 

Hey
I just got a Raleigh 20 ('71 green) and I want to make a fixed gear bike out of it. I was searching for a not too expensive wheel set. There are alot of 20" BMX wheels out there but can any of those hubs accomidate a fixed cog and lock ring? If so which brands? I noticed some are "flip-flop" but that does not mean anything either way..I don't want to have to build one from scratch! Thanks

Amazon has a 20" double wall flip flop rear wheel for under $25.00. They have the matching front also. Alex DM24 36H, 20 x 1.75", Silver/Silver Wheel Rear. I think the rim is fine but not the best quality hubs. It is a inexpensive way to go. If you find you like it you can upgrade later. I think the idea on flip flop hubs is to go singlespeed freewheel on one side fixed on the other, or just different sized cogs.

Flip-flop hubs are designed to have a fixed cog/gear on one side and a one-speed freewheel on the other in case you'd rather coast. Only one side is threaded for a lockring, so you can't put a fixed gear on both sides without running the risk of having that gear come off sometime when you are slowing down.

Actually, a "flip flop" BMX hub might be threaded for freewheel both sides - so that you can run two different ratios. You're right not to assume that either has lockring threading - make sure before purchasing.

Just to say be aware that track sprockets won't fit onto some bmx hubs, or to be more specific, they will fit but bmx hubs aren't reverse threaded so you can't add a lock ring that keeps the sprocket on. You can, of course, make a 'suicide hub' this way using loctite or similar metal glues but this doesn't come recommended.

I built my own 406 fixed wheel after tying out a suicide bmx myself with a proper track hub - something your local bike shop might find amusing but should be able to do nonetheless.

So how did you like it? I've never ridden a fixed but the idea really appeals.

I have a set a BMX wheels that I bought second hand for my Twenty project. The rear wheel has threads on both sides, but one has a smaller diameter than the other.

How can I tell if it’s suitable for a fixed wheel? What would be a recommend gear ratio for a fixed Twenty with a newbie rider?

It's not suitable for a proper fixed gear wheel. A proper fixed gear wheel has threads as you have them on your wheel (the larger diameter side), but the threads are shorter. And then on the same side there are smaller threads that go in the other direction. Those are for a lock ring to secure the cog. You can still use your wheel as a fixed gear wheel, but you'll have to use a setup called "suicide" setup. For that you'll screw on the cog and than screw on a BB lockring on the same threads. Obviously this is not as safe as the proper setup.

Track/fixed gear hub (notice the second, smaller threads)

http://sheldonbrown.com/fixed-conver...l#freewheelhub

You probably have the second (BMX) type flip-flop hub

Sammyboy, LittlePixel and Rincewind are correct, "flip-flop" in the BMX world is not the same as "Flip-Flop" in the fixed gear world. (I am sure Flip Flop has many meanings in other worlds as well)
Looks like I will eventually be building a wheel up from scratch.
Suicide hubs ain't for me. I got no health insurance!




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I just got in from a 12 mile (each way - 24 in all) commute on my Twenty and am still enjoying it very much. It'd actually been a while since I rode my Twenty any distance - my 700c Peugeot has a nicer saddle and I've been riding that a lot recently - but a flat tyre when I went out to the yard this morning dictated that the little minx was taking me to work today.

How do I like it? It's great - I think people assume going fixed will knacker out your legs and be more tiring but something about the constant and varied effort seems at least to me less tiring than the on/off coast/ bursts of exertion way you ride normal bikes. Ideally you need a good ratio set up (again - peruse Sheldon's excellent gear calculators for this) for the type of place you ride. No good having a good long gear length if you live in the middle of hills and have to walk your bike up most of the hills. I have both my bikes fixed and have set them up so they have very similar ratios, despite the fact one is a 700c 80s tourer and the other a 406 wheeled 70s shopping bike. My Raleigh (check out my site - link in my footer if you want to see it) has a rear sprocket of 14 and a front chainring of 54 teeth giving a gear 'inch' measurement of about 72 inches. On my Pug it's 14 ->38 which gives around 71, making my twenty actually a bit faster with the same amount of effort put in.

You have to get used to the idea of the pedals ruling you - there are plenty of 'how to ride fixed' guides out there but I'd say give it a go and see if you like it. Not one to get all mystical, but there's something really relaxed and zen about being connected - especially with SPD pedals - to the bike and the road. Plus you get to be in a club where other fixie riders will acknowledge your prescence, which is more can be said for most commuters or the lycra crowd. ;)

you guys are great!

Suicide hubs
 

The reason the safety police are so intent upon lock rings is so the torque of back pressure doesn't unscrew the ring from the hub and cause an unpleasant accident. There are a couple of ways around this, Locktite, using a bb ring to snug up against the cog (if you have enough threads), or run a rear brake. I use both of my brakes on my Twenty and have run a regular single sided bmx hub for 4 years. Never had an issue. If I relied on back pressure for all my braking, I'd probably set things up differently.

I use a bmx wheel with a track cog and loctite red. It has worked well for me for the last two years on a 20 inch and 16 inch wheel.I never try to lock up the rear.I run a front brake on both bicycles, but mostly ****** the pedals for braking.

Proper stopper!
 

Thanks for the info! I get it now. I'm a little disappointed, I thought I possibly had the right hub. So I think I'll make that single speed and save up for a proper track hub.