DROPPED MY BIKE!

[Sev]

I have a pair of cheap ones fixed to mine. They're also called:
Crash Bungs
Crash Bobbins
Tampons (french... I swear to god)
Frame Savers
Frame Sliders

amoungst other things. You can pick up a cheap pair on e-bay more then likely. I haven't tested mine yet, and I'm not even totally sure they'll save it, but they don't look bad, so I'll live.

[omar]

btw, I never hear anyone talk about this here, but from what I remember, at the MSF course, the insructors told us how to get out of those lock ups:

Front wheel lock...
If the front wheel Locks on you, the advice was to release the front brake, straighten out and then brake again. If you keep trying to brake during that lock you'll go flying off.

Rear wheel lock...
The opposite for the rear wheel locking, the advice was to just apply rear brake harder if the rear wheel locks.

That's what I remember. Anyone else?

[flynrider]

Rear wheel lock...
The opposite for the rear wheel locking, the advice was to just apply rear brake harder if the rear wheel locks.

That's what I remember. Anyone else?

I'm curious about this last one. If your rear wheel is locked, how does applying more rear brake help??

[Dirtytoes]

Tampons (french... I swear to god)

lol

btw, I never hear anyone talk about this here, but from what I remember, at the MSF course, the insructors told us how to get out of those lock ups:

Front wheel lock...
If the front wheel Locks on you, the advice was to release the front brake, straighten out and then brake again. If you keep trying to brake during that lock you'll go flying off.

Rear wheel lock...
The opposite for the rear wheel locking, the advice was to just apply rear brake harder if the rear wheel locks.

That's what I remember. Anyone else?

true, they told us that too, it's alo in the booklet they gave us....but at the time of the crash you really don't have time to think....it all happens way too fast....you don't really have time to think hmmmm what was it the instructor told me?.........also, this was my first crash/drop........and it was later that i found out the wheel locked......at the very first i thought it was because of the water on the ground.

Rear wheel lock...
The opposite for the rear wheel locking, the advice was to just apply rear brake harder if the rear wheel locks.

That's what I remember. Anyone else?

I'm curious about this last one. If your rear wheel is locked, how does applying more rear brake help??

i think someone asked this during the msf.........i think its so that it keeps the rear wheel locked.

[scan]

Rear wheel lock...
The opposite for the rear wheel locking, the advice was to just apply rear brake harder if the rear wheel locks.

That's what I remember. Anyone else?

I'm curious about this last one. If your rear wheel is locked, how does applying more rear brake help??

If you don't leave it locked, when it begins rolling again, it will not be in the correct place to resume rolling - so begins a tank slapper. This is where the front and back cannot get re-aligned. The front and rear begin ocsilating and depending on your speed it may be violent. Nasty business that. The usual result of a tank-slapper is a high-side fall - where you go over the bike and into the air. If you stay on the rear brake you might be able to ride out the skid, or worse case low-side your bike - better than a high-side.

[flynrider]

OK, I think I get it. If the locked rear wheel slides out of the line of travel, then yes, it's not a good idea to let it start rolling again. I guess i was confused by the way it was put. I couldn't see how applying more pressure to the rear brake could help once it was locked.

Personally, I don't follow that rule to the letter. With my cheesy little drum brake on the rear, I occasionally lock it when clamping on the binders to avoid a mindless cage driver(drum brakes are touchy like that). It's very easy to feel and hear when the tire locks up, so I just let loose the instant I feel/hear it lock (assuming I'm going straight). The back end never has time to slide out of track, so it's a non-event.

I get lots of practice applying maximum braking in Phoenix traffic. If I do it right, both tires will be complaining, but still rolling.

[Shiv]

If the locked rear wheel slides out of the line of travel, then yes, it's not a good idea to let it start rolling again.

I could be wrong but I'm pretty sure your rear tire doesn't have much room to move around in.

The point of keeping it locked is so that your rear tire remains locked in place and CAN'T rotate at all. You'll skid, sure, but that's better than tank slapping.

The reason you don't want to let go of the rear brake is because your front wheel is spinning at the speed you're going. Your rear wheel, however, is not moving (or moving a lot slower) and thus when you let go it has to speed up to match the front wheels movement. This creates two gyroscopic effects instead of just one (what you want) and the two forces conflict and thus the bike goes out of control and then you go high siding.


I believe that's how it works from my limited knowledge of physics.

[flynrider]

It would seem to me that as long as the two gyroscopic forces were in a direct line with one another (on the same plane), it wouldn't matter if one was less than the other. I would think you'd need to have one of the two forces getting out of line to start an oscillation like a tank slapper.

The problem with the locked rear tire is that the lack of gyroscopic stability will cause the rear end to drift out of line easily (that fishtailing effect). If you let it start rolling once it's not pointing in exactly the same direction as the front tire, then you have two gyroscopic forces that are not on the same plane. The back tire wants to go one way and the front tire wants to go a different way. The bike will oscillate between the two. That is where the tankslapper is going to start.

Anyway, that's the way I understand it. Like I said, I occasionally lock the rear tire in a hard stop and I don't go unstable as long as I let off the rear brake while the rear tire is tracking straight.

[scan]

Exactly right - if you are in a straight line it is not relevant. If the wheel lock and rolls in a straight line you will feel no effect. The problem being if those two planes come out of alignment you might now notice until you let go - this is why MSF says keep it locked. I notice I lock quite regularly on my bike and it causes me no disconfort now. It is always in conjunction with a full power stop and I'm bringing the front brakes in with quick even action at the same time.

[tcreeley]

I went down today- simple - it was raining - It had been snowing and sleeting and I was headed home after work- gn400- I figured I'd go slow- road was cold and wet- slush beside the road. I went to pull off on the soulder to let a pickup go by so he wouldn't be tailing me. I slowed way down and was just pulling off the pavement when my front tire hit a soft bit of wet dirt and down I went. My bike tipped toward the road. Cracked a turn signal. Pain to lift it back up. It felt dumb to do it!

I've always hit the rear brake before the front brake- and never just the front brake. It seems like the momentum has to go some place if you stop that front wheel from turning the same speed as the back wheel- and that flips you at high speeds or tips you at slow speeds. This is the 3rd time for me- slow learner- each time I was going less than 5 mph. The first was a heavy front braking, the second- I ran into a small stone with the front wheel- coasting and today- soft patch of dirt. I got a light bike- so maybe that's more of a problem at slow speeds.

Good luck with the fix up. Do the work yourself and save the labor cost. ?
:frusty: