bonsai171

Hi,

When I switch my bike from fixed to singlespeed, I have to open up the caliper with the lever, but usually that isn't enough to get the wheel off. Usually the tire has to be deflated almost completely. Has anyone else had this experience, or are there brake calipers that open up more (without having to release the cable!)?

Dave

seau grateau

Maybe try setting the calipers so that they're a little bit more open when in their closed position. What size tires are you running?

bonsai171

700 x 35

HTupolev

Some brake levers also have releases on them, allowing them to let out a bit more cable.

What's the outer width of your rim? If your tire is much wider than your rim, unless you keep your brake pads backed off far from the rim, it's difficult for any quick-release systems on caliper brakes to open wide enough.

Cantilevers (of both the center-pull and v-brake variety) do better, since you can just pop the cable from one side of the brake, making it behave as if the cable was removed. But your frame most likely doesn't have posts for mounting cantis.

JohnDThompson 

What kind of brakes and levers?

You can always remove one brake pad to get the clearance you need, if you can't open the calipers far enough with the QR device. Yeah, it's a bit of a PITA to remove and replace the pad whenever you flip the wheel, but at least in IMO it's easier than deflating the tire and pumping it back up.

bonsai171

The brakes and levers are both Dia compe from the 80's. I do like the brake pad trick, that's better than using up a CO2 cartridge. Eventually i'm going to go with 700 X 25s, so hopefully that problem goes away.

Dave

seau grateau

Should be fine with 25's. I'm able to squeeze 28c Paselas through my brakes without much trouble. In the meantime another option would be unscrew the bolt that holds the cable so the caliper opens up completely, then reset and tension the cable after you make the switch.

TejanoTrackie 

The only way to get tires that wide to fit through the brake pads is to mount them on wide rims so you minimize the lightbulb effect.

EpicSchwinn

Or use canti brakes. My cross bike has 35c tires and I can remove them without deflating since it has cantilever brakes. Either way I think downsizing tires is going to be his best bet.

Maybe OP should just go brakeless and forget the flip flop???

Altimis

Use this if you really need that much fat tires

bonsai171

Originally I only had the front brake caliper on (need at least 1 brake for singlespeed!) It felt kind of wierd in hard braking. Maybe it was because I put the brake lever in the traditional location? Would it help to mount it to the upper part of the drop handlebars kind of like a flat bar?

Dave

TejanoTrackie 

You always want front AND rear brakes with a singlespeed setup. With a fixedgear setup, you can backpedal to provide braking to the rear wheel. In very slippery conditions front wheel braking is very limited and if you lock up the front wheel you will lose control of the bike and crash, but you can skid safely with the rear wheel because the bike remains stable. If you want more good information on brakes I suggest you read Sheldon Brown.

bonsai171

How do you do a skid stop?

TejanoTrackie 

I'm not sure what you are asking. How do I do it or how is it done ? Anyway, my point was just that you need some way to brake the rear wheel in slippery conditions where using the front brake can be a problem.

bonsai171

How is skidding done? I'm wondering what the options are, so it would help to know how to do this.

Dave

TejanoTrackie 

OK I'm not a skidding expert, so I'll let others chime in on this subject. If you do an internet search, you will find plenty of discussion and explanation on how to do it.

JohnDThompson 

Only realistic if the OP's frame already has the bosses for mounting cantilever or V-brakes.

EpicSchwinn

Single speed:

Pull your rear brake lever as hard as you can until the brake locks up.

Fixed gear:

Find out what your dominant foot is. If you don't know, stand facing away from a friend and close your eyes. Relax and tell them to push you forward without telling you when they're going to do it. Whichever foot you step forward with instinctively is your dominant foot. Now get on your bike. Good foot retention like straps or clipless pedals is necessary. Ride along in an open, level area like a parking lot. Prepare to skid by shifting your weight forward on the bike to "unload" the rear wheel. The less weight over your back tire, the easier skidding will be. Beginners will find it very difficult to skid while seated so feel free to put your nuts to the stem while learning. When your dominant foot is forward and just a little lower than horizontal, yank up with that foot while pressing down with your non-dominant foot. It takes a sudden jerking motion to break the momentum of your spinning wheel. You will eventually develop good enough strength and timing to skid with more weight over the back wheel which makes it more effective for stopping.

If you plan to skid regularly, be aware that on a fixed gear bike your tire will always be on one of several "skid patches" when your feet are in the correct position to initiate a skid. The amount of skid patches on your tire is affected by your chosen gearing. More skid patches = more even tire wear. To calculate the amount of skid patches you have, take the amount of teeth on your chainring over the amount of teeth on your cog and reduce the fraction. The numerator of the reduced fraction is the amount of skid patches for that setup.

Here are some examples:
48T chainring with 16T fixed cog. 48/16 = 24/8 = 12/4 = 6/2 = 3. If you have this gearing, you will always be skidding on the same three patches of your tred.
52T chainring with 18T fixed cog. 52/18 = 26/9. The fraction cannot be reduced any further. With this gearing you have 26 skid patches.
Wanna make this easy? Just buy a chain ring with a prime number of teeth. I always used a 53T chainring when riding fixed gear. It cannot be reduced so you have 53 skid patches no matter what gear you run in the back.

Zoroman

Dave---I am just wondering, how long have you been riding a bicycle? Have you never ever ever skidded?

bonsai171

I used to skid with my disc mountain bike, but never had a fixed gear bike till recently.

Dave

AlmostTrick

When I have this "problem" I just adjust the brake cable to where I can remove/install a fully inflated tire, then bring the pads closer to the rim with the barrel adjuster(s) at the lever and/or brake. Set correctly no tools or removing of pads is required, only spinning the barrel adjuster by hand.

Basically when in the ready to ride position the barrels may need to be near full extension. Then you just spin 'em closed to remove the wheel.

Altimis

You're right, I forgot about "mounting", you need fork or add bosses for mount this type of brake.