Oh No!

GoldenMotor.com

Fulltimer

New Member
Aug 13, 2010
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Saint Augustine, FL
Look what happened to me today. I was going up hill in the bike lane of a 4 lane highway when...........it hit the fan! The drive chain came off and the disc brake destroyed my new Monark Fork and destroyed itself in the process of all this. The front tire locked up and skidded until I got stopped. I was very lucky I didn't go over the handlebars. I was doing about 20mph at the time. There was just enough sand on the road that the tire didn't grab. All I got besides a bruised ego was a small burn from the exhaust.

Terry





 

Fulltimer

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Aug 13, 2010
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Sorry, I didn't make that very clear did I. One didn't cause the other, sort of. It might have. The drive chain did come off and the disc brake did get destroyed. Why the chain came off I have no idea. I also don't know why the brake did what it did. I wasn't using it at the time But the disc and the rotor are toast. Nothing happened to the spokes! The disc brake was wedged into the spokes but they didn't bend. Just locked up the front tire.


Terry
 

zean

Active Member
Dec 5, 2010
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california
Thankyou Fulltimer for showing me that the monarch front fork and bracket collapsed and you weren't even on the front brake. The sand was a blessing in that it prevented the bicycle from mousetrapping by allowing the front wheel to skid when front wheel lock-up occurred. Your balance, concentration, shoulder, arm and forearm strength are very good in preventing you from falling off your motorized bicycle while unexpectedly and suddenly skidding on a little bit of sand on the road at 20 mph.
 

MotoMagz

Well-Known Member
Aug 2, 2010
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Michigan
Glad you are ok.The front fork bracket..is that something that was made to adapt the disc brake?It just doesn't look original to me.If it was loose to give you fork action could it of twisted over a bump and sent everything into the spokes perhaps.
 

Fulltimer

New Member
Aug 13, 2010
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The blame for all this doesn't fall on the brake or the fork. I think that falls on me. I put it together in an unorthodox way to try and fix another problem.

If the wheel was centered between the forks, like it should be, then the disc was too far away from the caliper. If I moved the wheel closer to the caliper so that they would mesh, the tire was rubbing on the fork.

So what I did was to center the tire and mount the caliper on the inside of the caliper mounting bracket. That lined everything up. The brakes were a dream to use! I double checked to make sure everything was tight. But I honestly can't say that something wasn't loose. But getting back to that caliper and its mounting plate. The caliper is supposed to be on the outside of the mounting plate.

But what actually happened I don't have a clue. I have enough confidence in the setup though that I will get another identical setup and put it on.

Terry
 

Fulltimer

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Aug 13, 2010
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Motomagz: you reminded me of something that I completely forgot about. Something I was going to check before putting the brake on. The fork wasn't wide enough for my tires. So I told the guy that did the painting to spread the forks out. I was going to do some measuring before I put it together and didn't. That explains why I had a very hard time getting the rim into the fork. He twisted the fork. In other words the 2 forks on each side were not square with each other. That is what I forgot to check. I'm sure that had a part in what happened.

Yes, there is an adapter that makes the Monark use a disc brake. That part works fine and I'm sure it had nothing to do with this mess.

Terry
 

happyvalley

New Member
Jul 24, 2008
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upper Pioneer Valley
Good news the only damage was bike parts.

There is a condition called torque steer that early mountain bikers found out about when using discs, all the stopping forces are transferred in an asymmetrical manner to just one fork leg. Bike designers began to account for that. It may not apply, but I thought it worth mentioning as you unravel the forensics of what happened.
 

Fulltimer

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Aug 13, 2010
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Saint Augustine, FL
Good news the only damage was bike parts.

There is a condition called torque steer that early mountain bikers found out about when using discs, all the stopping forces are transferred in an asymmetrical manner to just one fork leg. Bike designers began to account for that. It may not apply, but I thought it worth mentioning as you unravel the forensics of what happened.
I can see that happening. It did twist to the left, the side with the brake. It even turned inside the head tube. When I turned the handlebar so it was straight the wheel was turned some to the left.

Terry
 

Venice Motor Bikes

Custom Builder / Dealer/Los Angeles
Mar 20, 2008
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Los Angeles, CA.
WOW!?!?!... I'm really glad you didn't get hurt!!! :eek:
I've never seen that happen before!!
I'm guessing that when your chain came off, you did a super 'Popeye' grab on that brake lever. (not that that makes this ok to happen...)
I've designed a totally different Monark disc brake mount that will come out very soon that will be twice as thick as the old ones... I'll take care of all this!
 
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Dontwannawalk

Member
Dec 23, 2009
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Iowa
Hmmmmm! Sounds like something I've experienced but, mine was due to new V brakes set too close to the rim & a little sand on the street going down hill. I'm replacing the broke clutch lever, putting on a new brake lever and am just about done wearing a splint on my left arm for the last six weeks to immobilize my dislocated left thumb. I think that's what broke the clutch lever. Lesson learned :( TRY OUT THE NEW BRAKES BEFORE YOU GO DOWN THE HILL!!!!.duh.

P.S. THE SKINNED PATCHES ON MY HEAD, SHOULDER AND KNEE ARE ALL HEALED UP, JUST A LITTLE RED.