Posts
53
Joined
2/5/2019
Location
AU
Edited Date/Time
5/21/2020 5:16pm
Hey guys! So just a simple one to help pass some time,.
Tell me a story of your weirdest problem that led to a failure or stoppage..
I’ll kick things off.
I was competing in a desert race. About 3 days in a stick flew up and perfectly bumped the fuel tap to the off position.
The bike ran long enough for me to forget the stick hitting my leg and the bike stopped:.
Frantically tracing spark, fuel and electrical possibilities
The tap wasn’t marked so wasn’t clear which was off / on so it took me a good 2/3 minutes to figure it out while bikes were flying past me! lol
Tell me a story of your weirdest problem that led to a failure or stoppage..
I’ll kick things off.
I was competing in a desert race. About 3 days in a stick flew up and perfectly bumped the fuel tap to the off position.
The bike ran long enough for me to forget the stick hitting my leg and the bike stopped:.
Frantically tracing spark, fuel and electrical possibilities
The tap wasn’t marked so wasn’t clear which was off / on so it took me a good 2/3 minutes to figure it out while bikes were flying past me! lol
I was riding at a club track Saturday that has a big step-down jump landing on a steep downhill straight.
Just as I was grabbing gears to hit that jump I saw another guy waving his arms to slow down.
Someone must have crashed on the downhill, hope they're ok.
I rolled slow over the jump, across the flat and over the edge of the downhill. There were three or four people spread out all over the hill looking intently for something on the ground. A lost contact lens?
I gave them a wide berth while watching out for any track junk that might snag my tires.
Near the bottom of the hill I noticed one of the people was a close friend holding a front sprocket with an OH-SHIT look on his face.
His front sprocket popped off without binding up the chain down a very hard, rocky 4th to 5th gear hill after a 50 foot step-down and he didn't crash. That's a lucky day!
later pulled the head off and it only had minor damage. replaced the piston, sanded the head a little and raced the rest of the season
The Shop
He put it on later and called me up later and could not believe how good it was running. He put the spark arrestor back on and said it ran like shit, then he put the stock silencer back on again and it ran perfect. Only the second time I’ve ever heard of the silencer being a problem like that.
I was friends with the Kawasaki dealer and the bike still had it's 6month warranty so I easily got a new cylinder (and piston I think). They said they'd never seen anything like that before.
You've been soooooooo lucky.
Bout 6 months ago was riding at one of my local tracks and put a new plug in my Cr250r after I leaned it out. Rode the entire day and on my last moto the spark plug rattled its way out. Thought I blew a hole in my piston.
On my trusty Cr125r I had quite the amount of rear brake problems. Blew a few seals then got the bore cleaned up. Got a ride or 2 on it where the brake was completely fine. I was riding my backyard track when I lost my rear brake for probably the 3rd or 4th time on this bike. Assuming it was still the bore I threw the bike in the back of the truck pretty frustrated. Once I got home I looked at it for a further inspection and there was brake fluid everywhere, come to fine out my sight glass fell out.
I’ve had a few more smaller ones. Definitely had a few front sprockets fall off from my Honda 2 strokes. And this year at wild boar gncc I completely tacoed one of my foot pegs and didn’t notice it till I was washing the bike.
Moral of the story, always do a compression/leak down test first, no matter if you think it's an electrical or fuel issue.
If you've ever ridden down old railroad tracks (after they've been removed) , you probably remember seeing lots of railroad debris - spikes, pieces of metal, etc. I always figured the odds of getting a spike positioned just right to go into a dirt bike tire were slim to nil.
I Can confirm that when you do find just the right spike at just the right angle, it does make a big hole in the tube/tire and you realize pretty quickly that you have a flat!
Pit Row
Luckily I was on loose soil and it was actually confusing for a moment as It suddenly was quiet and there was a floaty feel as the bike drifted to a stop.
Nearly every single part of the engine was destroyed including cases. Was unable to find what actually went wrong due to the complete destruction of the engine.
Suddenly became shy about high revving expensive 4 strokes 😝
Awesome stories! Keep them coming!
2 - the silencer grid broke, blocking 30% of the power
3 - the rubber mount of the carb cracked (on a 6 months old bike)
4 - a dick sabotaged my new bike in SX, putting a bit of sand in the gearbox when not watching
5 - clamp broke and snap my brand new road bike in half, noticed it just after stoping the bike
6 - rear master cylinder broke (on 2 years old bike)
7 - plug popping out cylinder on a car
8 - red 4 in 1 cracked on a car
9 - broke ABS on a hard emergency braking on a car
10 - exaust fell off and exploded rear tire and wheel on a car on crowded, wet highway
11 - broke alternator on a hydraulic controled car (steering, brakes, suspensions)
As none of the above resulted in a crash, i decided to take it easy from that point, i guess it is not bad ass but that is enough warning candles.
For some reason or another, I had the idea to lay the bike on it's side. I did that. Then I flopped it down on its wheels, and removed the flywheel inspection port. It was evening, the sun was setting, and I kid you not, a ray of light from the last vestiges of sun shot across the prairie and shone directly on the valve tappet adjuster screw sitting in the bottom of the case, visible from the port. It was like Indiana Jones in the map room when the light shines down the pendant to reveal the location of the Ark!!!
I put both of those back on with a new nut, and the bike ran for another 10 years.
Kicked it over and it cranked right up (engine ice cold). BUT, throttle stuck wide ass open. Tried a few things to get the engine killed but nothing worked. After about 20 seconds, there was a “clunk” and it stopped running. After disassembling, found the piston, cylinder and head toasted, and the crank blew apart taking out both case halves.
Glad it happened in the driveway and not on the track. Needless to say, I check the damn throttle all the time now.
At first I figured it must have flooded lying there the way it did, and I figured it would clear out shortly. It didn't. So then I thought the assumed flooding must have fouled the plug. So I stopped trailside to change it out. That would fix it, right? It didn't. Still ran like crap. Could barely keep it running, and stalled several times. It would refire, but barely ran.
It was the last lap, so I just cut it short and headed back to the pits and loaded. During bike cleaning, I discovered that the choke lever had somehow been depressed- likely during my crash. How that happened I have no idea. But raise the choke, and Kablam, runs like new.
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