Coaster Brake Challenge
Pics from last Challenge
Click Here for the write up in BIKE Magazine
Click here for write up in Mountain Bike Action.
To have fun, to race, to sweat, breathe hard, to ride hard, to challenge ones self. This is the anti-race race. Don't kid yourself it's hard, you may crash or puke (or both) but we are down for the fun and camaraderie more than the podium. Well, there is no podium but I think you get the point.
We will be hosting 4 Sunday races in the month of July. Each race will have a meet point at 7am and race at 8am or so. Most races will be short 1 to 2 hour affairs. Meet points and descriptions of each race will be posted so you know what to expect. Otherwise, course locations will be kept off the web. Don't call or e-mail for details please. We have a pressing need to keep some information off the grid so to speak, hope you can understand and respect that.
This race series is open to all comers. Men, women, kids, we don't discriminate. Come with a smile and leave with a smile (and perhaps an impressive scar.)
A note on races:
Some of these races are fun to watch and can be easily accessible for speciation. On a scale of 1-10, 10 being best the ability to spectate will be rated. a score of 10 equals you can see 100% of the action, score of 1-4 mean you can camp at a spot and see riders pass, higher scores mean a looping feature in the course where you can move from point of interest to point of interest to see the action.
We're not the only ones out there people, so you will need to yield to horses and peds as best you can. The higher the number, the more Meat Pylons you'll have to deal with. Ride safe and be respectful of others. As a bikers you have to yield to peds and horses, keep that in mind. On hot days, expect the number to be lower. It should be hot or cold or both, it changes nothing, your suffering will be the same as the fires of hell, or waiting in line at the DMV. Bring water, you'll need it.
The higher the number the better chance you'll be walking a few sections or have your white knuckles break through your gloves as you fly over your bars. 1-3 would be near flat non-technical type stuff, most will fall in the 4-7 range, and a 10 would push the limits of man and coaster brake to the limit. There's nothing wrong with having to dismount to traverse something you would not feel comfortable doing. Courses are designed with the limitations of the device in mind so don't worry! The goal is to have fun.
Rules for bikes:
Single speed only. No internal geared hubs (sturmey-archer, bendix two speed kick backs etc.) no derailleur of any kind (A chain tensioner is fine). No external gearing. No gears. No fixed gear. Each race will be different from the last and you may want a different gear ratio for each race and you can have any gear ratio you wish. We have found that 30-36 in the front and 18-22 in the back is the range best suited for this event, see what works best for you.
The rear hub must be a coaster brake. Single speed coaster brake only. No two-speed kick backs, etc (I know what they look like) Some coaster brakes are better than others, do your homework and get a good one. See below for more info. Cranks of any kind may be used as well as pedals.
Coaster brake only on the rear wheel only. No hand brakes of any kind. No secondary braking system of any kind. No drum brakes, no cables, rods, levers, etc of any kind. You pedal forward to go forward and back to stop. Nothing else.
Preference for old double bar cruisers but there are no frame restrictions. We have found that cruiser frames and lower end frames with a horizontal dropouts work the best. Frames with a rigid/vertical dropout are difficult to get proper chain tension. We recommend the following types of bikes:
Single speed mountain bikes
Pros: take new bike goodies well, light.
Cons: Can be costly, hub spacing is 135mm and coaster brakes are 110mm. There are some 135mm coaster hubs out there now. It will take some work to get the wheel to fit well. can be done with an axel swap and spacers.
Pros: Cheap and look cool too! Already have to correct spacing for a coaster brake.
Cons: Don't take mountain bikes goodies like threadless forks etc. Most have 1 piece cranks. Heavy.
Any 26" bike that has a horizontal drop out.
Pros: Older Mountain bikes are cheap and plentiful and easily adapt to our purpose.
Cons: None really, an ideal choice for this event.
You can have any kind of hoop/tire combo. I suggest a light wheelset that you've laced a coaster brake into. Something rugged is good, I've done each race with cheap alloy cruiser rims, they have held up fine thus far.
Everything else is left up to the individual rider.
Here are some examples of bikes that would work great for this event:
This is a custom job. A bit over the top unless you want to go that way but you can build a purpose built bike like this one or take something else and make it work. The gearing on this bike is 34/19 for now. I'm going to test it out and see if I need to change things. The bike has performed well, the rider, not so well.
Here's my old trusty 1964 Schwinn. It normally has V brakes and a freehub single speed set up but for this race I laced up some old Arayas ala bmx with a Bendix red band. The gearing is 36/20 and I've been able to climb up some pretty steep hills this bad boy. Once you learn some control with the break, you'll seldom skid. You just have to descend slower than you would on a regular bike. I've had this bike for years and beaten the hell out of it, old Schwinns make Ideal platforms for this kind of event. Note the "1 1/8 threadless fork in the frame made for "1 threaded. The bottom bracket clearance is a little low, it's something to look for. This bike does have 180mm cranks however, standard sizes should be no problem. Most of the races are on fire roads so low bb clearance is not a big deal.
This, besides the paint job it the easiest to get going. Old Giant mountain bike frame with bmx drop outs welded onto the frame. Light Chro-mo steel and takes most semi-modern and inexpensive bike bits.
Old 50's era double bar cruiser. Some of these are "Middle Weights" and will not take a fat tire, you'll need to check it out before you commit to a build with one. Heavy, low bb height on most, but you win on style points. This one is my personal racer. Works well.
Which hubs are good? (the tech section)
Not all coaster brake hubs are built alike. You'll need a good one to hang tough in this event.
They are ok, best around for a new hub and easily found. They spin really good and stop decent. For ease of accessibility and function, the Shimano hub is a solid choice. These hubs have a low brake modulation factor, they are grabby so you'll need to get acquainted with them before you roll out. Overall for accessibility and durability I'd recommend these over others.
When these get too dry they get grabby, you lose modulation. Shells last a long time, the guts not so long. I've swapped guts three times in the last two years. They work themselves loose fairly often. Cogs get stripped.
Hi Stop, Falcon, CSC etc.
Very common hubs found on most newer coaster brake wheels. These tend to get a little sloppy after a few hard braking sessions, repacking them does little to remedy the problem. Not recommended but will work if that's all you have. I have done 30+ hard miles on these hubs and they do work but they tend to fade on a long braking session.
These hubs lose breaking power as they heat up. The bearing races can crack and bearings can come apart if they get loose. These lower end hubs get loose very often. Once you really fry one, it's done. You may have to swap out the guts and shell. Cogs get stripped.
Junk. Weak. We've killed them in one ride or one heat or one descent. Velosteel hubs have mass appeal because they are not from Asia perhaps, but for our purposes they are woefully inadequate. Do not use!
Scary! They just stop working. No forward, no stopping. They spin great but must have some soft bits to fail so quickly. These hubs have versions that take track cogs which is really versatile, now if they could make them worthy of a 4 mile descent....
Bendix red band:
The king. Most of these were on kids bikes so they are not the strongest Bendix ever made but they are a crowd favorite. There are juvenile, normal and coveted tandem versions of these hubs that have different internals and regular or hardened parts. Juvenile hubs are going to be 28 hole and not be all that great to stop yo' fat ass. Most in any variety are in 28 hole, less common in 36. Modulate very well, durable too. Getting costly but still out there. The draw back of any hub no longer made is sourcing replacement parts. Also you can find a splined cog for these which will never slip, you need a plined clutch for it too though, never seen one above twenty teeth.
Loss of quick breaking action, you have to spin the cranks further and further back to get braking. Hub flanges can strip which means you die. Being that they are old, the shells can be very worn meaning that no amount of swapping new parts will help it. Limited cog selection, 22 tooth cogs are rare, 18-20 more common.
Bendix Knurled hub:
The brake arm will have "70" or "76" stamped on the torsion arm. Found on adult bikes, 4 brake pads in some 2 in others, very stout and common in 36 hole. Less expensive than red bands. Parts still around, you can get a 36 hole shell and pick up 28 hole ones on the cheap for parts. They come loose very easy.
Loss of quick breaking action, you have to spin the cranks further and further back to get braking. Hub flanges can strip which means you die. Being that they are old, the shells can be very worn meaning that no amount of swapping new parts will help it. Bang for buck perhaps a more sound choice than a red band, at least easier on your wallet.
Complicated clutch plate braking system. No one has used one in this event but we suspect they have a lot of fade in prolonged braking (so I was told by an original repack rider).
N & K. Seem to work well, snap ring fails, very hard to source parts for though (from Japan)
Perry, commet sachs etc. decent, not really tested one of these to the fullest.
Morrow: reputedly the best, never even seen one, hard to find and costly.
Sun Tour: So bad, even brand new they suck. Stay away!
Keep in mind old, obscure, weird gray market hubs will be hard for one to find replacement parts. You will wear stuff out. We murder coaster brake hubs.
Note: The cogs on some of theses are not the same as contemporary cogs, you may have to do some modification to make them fit. The biggest cog I've found for an older hub is 22 teeth but very rare, newer ones I've seen up to 22 you can get all day long. Shimano cogs don't fit Bendix hubs and many of the older hubs have a different mounting set up than a snap-ring. These older hubs are on a general level better than new hubs but sourcing parts for them can be difficult and costly. I recommend finding one of a little used girls bike as they tend to not be ridden hard or at all. You'll need to clean and repack the hub as the grease will act more like glue than lube once they have set for a time. I use boat trailer bearing grease, it's cheap and works great.
All hubs must be torn down and repacked with a high-temp grease or you will fry them!!
Bicycle grease is not strong enough, Lithium grease is not strong enough. I've been using a high temp marine grease that is rated to 600 degrees Fahrenheit and on long descents even this grease will loose viscosity and fly out of the hub. This means that these hubs can get over 600 degrees! After a long decent I can take my chewing gum out of my mouth and melt it on my hub shell, it gets that hot. There are really high temp greases out there but they are costly, the grease I use is found at any automotive store and costs around 4 bucks for a big tub of the stuff. Just pack the sucker full and you should be OK, you may have to repack your hub a couple of times before its all said and done. If you do not do this preparation, you will have failure and possibly ruin your hub.
Looking for a wheel set? Try these:
Bicycle Wheel Warehouse
Wear and Tear
Some of the pioneers of mountain biking used coaster brake hubs for downhill racing, we're using them for cross country racing and we're pushing them far beyond their limits. No matter which hub you get you will burn it out at some point, even the most stout hubs will fail when up against the abuse that the CBC throws out. Your hub should take no more than 1/4 of a turn of the crank to make it lock up, if you have to go more it is worn and will fail when you need it most. Once a hub is worn, it will fade quickly once heated up. It may brake well when not under constant stress but a prolonged braking session will cause it to fade to a dangerous point. Keep this in mind so you don't have your hub get weak on you all of a sudden. A prolonged steep descent will kill any hub in one shot. Hubs seem to have a sweet spot where they're broken in a break well, new ones are touchy and worn ones are sloppy. Just know that repacking the hub will only prolong life so long and replacement will be common place if you log long miles on your coaster brake bike.
Unlike your normal mountain bike, the coaster brake bike will take some getting used to. Braking should be started way before you normally would and be ready to ditch the bike if you get into trouble, you will. The best power position for your brake is the pedals either in 9-3 O'clock or 10-4 O' clock. You must learn to modulate your braking so you don't lock up the rear wheel, skidding means you're not stopping and tearing up the trail as well. You have no power if your cranks are in the 12-6 O' clock position, try to keep your cranks in the correct braking position, in time this will become a natural thing for you but you must learn it or spend time picking up your teeth with a broken arm. I've done some rides that would challenge anyone like JPL on my coaster, it can be done. After time you just get used to it being "your bike" and that's what you have to work with, it feels normal. You need to practice first before coming out, entering these races cold turkey will most likely result in injury.
For more info on coaster brakes:
Most coaster brakes are 110mm spacing. Most single speed mountain bikes are 130 or 135 mm spacing and contemporary mountain bikes are 135. The axel on your average coaster brake will be too short to fit in these frames, you'll have to swap it out for a longer one and add spacers. This is why an old cruiser or steel mountain bike frame works best. You'll also need a bike with horizontal dropouts so you can get proper chain tension. Contemporary mountain bikes with a fixed dropout will be hard to make work with a single speed, a chain tensioner may not work due to the coaster brake action, I've seen some used to desirable effect. I recommend using something cheap and old for this event.
Also if you need to calculate your gear inches:
Chain line and chain tension:
This is important stuff here, so if you don't know read up. Your chain line must be near straight, and deviation will likely cause your chain to fall off. This is double bad because not only do you loose your drive system, you loose your brakes. This can be "exciting" so make sure when you're putting your bike together you get that chain line nice and straight. Converting bikes with a fixed dropout can prove troublesome in this area. You may need to add spacers or have the wheel over to the drive side more than the other side to get a good chain line. You may need to put a longer axel in your coaster brake hub so it will fit your repurposed bike.
Also very important. As you climb you'll put a lot of stress on the frame and if your chain is loose it will come off. If your chain is too tight it will bind on the hub causing drag and potentially backing off the cones in the hub leading to a component failure. Your chain should have 1/8 to 1/4 inch of slack in it once it's on the bike. Frames with horizontal drop-outs work best for keeping the wheel from moving. Eccentric bottom bracket are costly and can fail where lugs and a couple of toothed washers have carried the day for over a hundred years now, why mess with success? Chain tensioners can also be employed.
I want to join but do not have the stuff to make a bike.
No problem, I'll have good wheelsets for about 70 bucks, you'll need tires tubes etc. and frames, and complete bikes suitable for this event. I can weld BMX dropouts on your steel frame. Let me know ASAP so we can get your rig dialed in before the race. Complete bikes should run in the 85-200 dollar range depending on what you want. Don't wait until a few days before to hit me up, I gotta work for a livin' ya know? I have a few loaner bikes, they are first come, first serve, I don't hold them for a racer, get your own bike and hold it as much as you want...
Rules for riders:
Bring stuff to fix your bike on the trail with you.
Entry Fee and what you get:
The Entry Fee is $20.00 for all four races, that's 5 bucks a race. You'll have to pay the 20.00 if you make one or all 4 races.
You get a T-shirt. They're different each time.
You get a Patch.
Perhaps some schwag, we'll see.
Each rider will get a number and you will be scored as thus:
1 point for finishing a race, 0 if you DNF.
1 additional point for a third place finish
2 additional points for a second place finish
3 additional points for a first place finish
Each first place rider (stage winner) will get a trophy made from old bike parts!
At the end of the series the point leader will be the overall champ. Best to show up to each race to increase your odds.
Sign up at:
Van Nuys, CA 91046
Show up to a race and sign up there!