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and while we're at it, maybe you need to stop pretending you understand physics!

http://youtube.com/watch?v=_OElP4JXouk

Uncle Ovipositor wrote:You've flown over your handlebars because you clamped down too hard on your front brake? Sounds like you need to learn how to ride a bike.

Which is it? 'Can't be done' or 'Only losers do it'?

Funny. Chubby little kid bites it, which later settles an argument on the PRF.

ubercat wrote:

Uncle Ovipositor wrote:You've flown over your handlebars because you clamped down too hard on your front brake? Sounds like you need to learn how to ride a bike.

Which is it? 'Can't be done' or 'Only losers do it'?

Howabout "can't be done by anyone who can handle a bike"? Or "can't be done in the way idiots who crash pretend that it happens"?

If you make the bike decelerate faster than you you're going to separate from it. You can do this with either brake, or both of them. If you need to stop extremely quickly and can only use one brake, the front brake's the way to go, but you need to be able to brace yourself to prevent ending up like Scott (and clearly the crash left some permanent damage). At most speeds, bracing yourself is not an issue because of the position you ride in. Stopping quickly at high speed it becomes one.

But the way it works in cartoons, where you slam on the front break and the back wheel flips up in the air on the axis of the front hub and flings you through the air? That's nearly impossible to pull off.

Sorry, Scott, but I can't see the video here at work. I'm hoping it's a film of someone riding a bike with only a front brake slamming it on as hard as they can and being catapulted over the bars because I've never seen that happen. I'm going to go out on a limb and guess that it's not.

Uncle Ovipositor wrote:Sorry, Scott, but I can't see the video here at work. I'm hoping it's a film of someone riding a bike with only a front brake slamming it on as hard as they can and being catapulted over the bars because I've never seen that happen. I'm going to go out on a limb and guess that it's not.

For those of you who can't see the video, it's a kid on what looks like a normal BMX/freestyle kinda bike, riding fairly slowly, clamping down the front brake and being thrown over the bars, exactly like it happens in the real world, just like what's happened to (I'm assuming) a whole bunch of us when we were stupid kids doing endos. If anybody here's done it on a motorcycle (I've seen vids) I'd love to hear about that, but not on this thread I suppose.

The reason this doesn't happen when you use the back brake is pretty obvious. Anybody who has a bike with a front and back brake can see how it works. Standing next to your bike, roll it forward at a slow speed (like maybe 1 mph), and lock the back brake. The rear wheel will skid. Roll the bike forward slowly, and lock the front brake, and the rear wheel will lift off the ground and above the front wheel, just like a sensible person would expect, just like it happens in real life, just like how a million kids have gone over the bars doing an endo.

Sorry to derail the conversation so far. Pun intended.

scott wrote:For those of you who can't see the video, it's a kid on what looks like a normal BMX/freestyle kinda bike, riding fairly slowly, clamping down the front brake and being thrown over the bars, exactly like it happens in the real world, just like what's happened to (I'm assuming) a whole bunch of us when we were stupid kids doing endos. If anybody here's done it on a motorcycle (I've seen vids) I'd love to hear about that, but not on this thread I suppose.

That kid is not trying to slow his bicycle down. That kid is trying to do a trick and crashing. He is riding a tiny bike and trying to endo as far as possible w/o flipping over, and doesn't make it.

While riding a bike, it's pretty common (and comes naturally to most everyone I've seen) to shift one's weight toward the back of the bike when breaking hard. Even in emergency situations, this seems to be instinctual.

I've had many situations where I've had to break hard on a road bike. I've even had my rear wheel come off the ground. I've never crashed or gone over the bars. When I was a BMXer, I went over the bars hundreds of times doing tricks. I was never surprised or shocked; I knew exactly what could happen.

Barring bad roads or catastrophic technical failure, I've never seen an ass over head moment that wasn't just poor bicycle handling skills or engaging in risky behavior.

Cheers!
Ben Adrian

ubercat wrote:The chain stays straight.

Again, when I ride with my most used gear combinations, the chain is straight. Always. A well selected inside chainring and cogset will allow you to ride with a straight, perpendicular chain most of the time. If there's a hill or headwind I also have the option of upshifting, at which point the straight chain is less an issue. I never have chattering or friction when riding with the 42T front and 13 & 15 T cogs in back, which is 90+% of the time.

ubercat wrote:No chain slack.

I'll give you that one. But, a properly sized and adjusted chain should never fall off and rarely bang against the chain stay. Plus, a little slack is desirable; lest you stretch your chain out frequently from all the front and back pedaling pressure.

ubercat wrote:Better grip, both foot and hand.

I don't understand this at all. I ride clipless. Are you suggesting that a fixie with cage pedals will give better grip than my Eggbeaters? I don't buy it. Hand grip too? How so? Isn't grip about the tape? I've never considered that I could have better grip with or without my integrated shifter/brakes.

ubercat wrote:Less weight.

I'm dubious on this one. How much does a good cogset, deraillieur set and shifters add? By my estimate they add about 1.5-1.8 Lbs (for an Ultegra 10 speed group) This is about the weight of a morning shit and a heavy-ass hipster bowl helmet. Since most of these guys are riding old steel frames I have a hard time buying into the less weight argument. You could easily drop 5-7 pounds or more just switching to an light aluminum or carbon frame, if weight is such a critical issue. Wheelsets, tires, etc... can all drop just as much weight. I'm not seeing too many fixie hipsters riding with expensive tires and wheelsets though, so maybe it's all economics here.

ubercat wrote: Less systems to fail.

How often do your "systems" fail? I've never had to fuck around with a derailluer or cogset. If you have decent components, treat your bike well and keep it tuned, you should never have "systems" failures to the point where you can't justify keeping them.

ubercat wrote: More weight allowance for critical systems.

Critical systems? What critical systems are there other than brakes? Lights? Radar Altimeter? GPWS? Two-way radio? Giant messenger bag? Maybe lights.

ubercat wrote:Better skid control.

Perhaps. But I think that skid control has more to do with balance and lateral acceleration or deceleration recovery than how many gears or not you're riding with. Not buying it.

ubercat wrote: Quicker acceleration.

What could provide quicker acceleration then having a higher gear to start out in? This is ludicrous. I regularly out-accelerate fixie and single-speed guys on a daily basis, because I can upshift and get a lot more power going from a stop than they.

I guess I'm being a tad bit pedantic here, but I just don't buy the justifications. I guess if you enjoy riding them, that's all the justification you need. "Simple" and "cool" should be good enough.

Sorry, I'm not convinced of the advantages claimed.

What I want to know is how I can shorten my chain using regular-guy tools. I've figured out how to undo it, but do I need a special tool to take a link out?

And are 28" wheels excessively big?

Verbs and Nouns wrote:What I want to know is how I can shorten my chain using regular-guy tools. I've figured out how to undo it, but do I need a special tool to take a link out?

And are 28" wheels excessively big?

It depends on the type of chain. some have an oversized link in them with a pin that twists out, but you probably don't have one of those - which is a good thing.

Most chains need a chain tool to remove a pin, which will cost you about $10, It's very hard to modify a chain without one, but it can be done with a hammer, screwdriver, needlenose plyers, and a helluva lot of luck. You've probably got a 40% chance of getting a pin out that way and 30% of getting one back in without completely destroying the link.

I'd buy the tool.

Uncle Ovipositor wrote:

Verbs and Nouns wrote:What I want to know is how I can shorten my chain using regular-guy tools. I've figured out how to undo it, but do I need a special tool to take a link out?

And are 28" wheels excessively big?

It depends on the type of chain. some have an oversized link in them with a pin that twists out, but you probably don't have one of those - which is a good thing.

Most chains need a chain tool to remove a pin, which will cost you about $10, It's very hard to modify a chain without one, but it can be done with a hammer, screwdriver, needlenose plyers, and a helluva lot of luck. You've probably got a 40% chance of getting a pin out that way and 30% of getting one back in without completely destroying the link.

I'd buy the tool.

Nah, it's got a little clip that you slide off, and the chain comes apart. It's not a life or death thing, but the chain's got a little too much slack. I moved the back wheel as far back as I could, but the chains still got about an 1.5" play up and down. It won't slip off the sprockets, but I'm scared it will.

geiginni wrote:Lots of things.

You should try riding a track bike sometime - it's pretty cool. They do have a little more snap to them, which I assume is because of the simplicity and not having the chain slack riding around a few extra cogs. I don't know why, exactly, but they do.

The weight issue isn't going to be a factor if you're buying a bike to look cool, but for track bikes it's a big deal to get rid of the larger, freewheeling hub in back as well as the gear cluster.

Having said that, I ride with gears because I don't ride on a track and have hills to climb every day. Nothing against fixies or the hipsters who love them, it's just now how I ride.

And I'm glad to hear someone else rides eggbeaters. Brilliantly simple design.