Object Lesson

[OTB]

I've written a couple of times about "Decision Trees" in the role of problem solving and decision making; they are a logical process for eliminating extraneous or erroneous data or assumptions in order to form better decisions or solve problems.

In using a decision tree, you start at the beginning or simplest part of the process and test through yes/no, go/nogo processes to eliminate wrong answers. In effectively troubleshooting motorcycle systems we need to employ the same process, to avoid getting "lost" or defeated in the problem, and to avoid spending money and time on "answers" which do not fix the original problem.

It's like starting the bike; I sit down, grab the handlebars, thumb the starter button, and nothing happens.

Now what? Time for a major engine rebuild? Maybe I've blown a headgasket?
Perhaps the starter is fried? Solenoid? Relay? ECU? Hundreds, if not thousands of dollars thrown away at the parts guy and some pimply-faced "mechanic" who'll forget to retorque the flywheel and toast my new motor?
About that time I realize I've left the bike in gear and the interlock is keeping it from starting.................

You laugh?

I see it happen on this board and others all the time... bike won't start and the owner publishes the "problem" and a hundred folks start listing all the dire stuff it might be. I get depressed for the guy just looking at all the stuff and guess the cost in money, time and frustration this guy must be feeling.

Happens all the time.

I bought a spotless Ducati ST2 from my neighbor at a ridiculously low price because the guy had a stalling problem on decel whenever he did any heavy braking..unnerving when your are throwing it through the turns in the mountains and nearly wreck at every hairpin. He took it back to the Duc dealer and they diagnosed it as a short in the brakelight actuating system, charged him a couple hundred bucks in parts and labor after having him bikeless for a couple of weeks, and sent him on his way.

Next weekend he nearly gets hammered by the guy behind him when his bike stalls out AGAIN at the entrance to a steep turn. Bike goes back to dealer, they keep it for a month, replace the control module, charge him a lot more cash, and send him on his way.....next weekend...same sh*t again. This goes on for a couple of months, he gets more and more disgusted and one day when he has it idling out the driveway, I amble over to admire the nice bike, remarking how nice it sounds and how pretty it looks.

He turns to me and says, "You like it? You can have it for $3000." My eyes nearly bugged out of my head. He told me the story, and my computer-like mind figured I could spend another grand getting it fixed and still come out ahead, so I ran home and broke the piggy bank.

I gave him the cash, he gave my the bike and title, smiled, and wished me luck.

I took it back to the dealer, they kept it for a week (Christ, I know nothing about DUCATIS, right?). The service manager gives me several possible scenarios, all expensive, and none of them "feel" right to me....something in this whole process feels "off". So I give 'em a hundred bucks for "diagnostics" and take the bike home.

Take it off the truck, put it up on the centerstand, pull up a milk crate a few feet away, pour myself a cup of Earl Grey tea and sit and ponder..........

After a few minutes, I go in the house, get my gear, go warm up the bike and ease on out the driveway and rattle round the neighborhood till the temp needle pops up a bit, then run down to this quiet downhill stretch near my house and goose it a bit.... come flying down the downhill section and grab a big handful of Brembos.......bike stalls out.....over and over again.

Pull back into the driveway, shut it off, go fetch a fresh cuppa, sit back down and ponder some more.

Now at this point of my life I don't know squat about Ducatis, but I know enough about motors to know that in order for one to work, it needs air, fuel, compression and spark, and that if a motor stops running, it's because one or more of those properly timed and measured elements is missing.

I don't have any fancy diagnostic gear and the Ducati dealer did and he couldn't find any electrical (spark) issues, nor could he find anything wrong with the FI. I can hear the bike sucking down huge lungfuls of air, and the airfilter is clean so that likely ain't it..... and I KNOW it's got great compression 'cause when I'm braking and she stalls out the rear wheel starts to slide.........

So, it's time to go look at the basics; take the plastics off and check every electrical connection, every hose connection and clamp. Retorque every exposed nut a bolt.

I don't know what kind of gas is in the tank, so I tank my 5 gallon can and go pick up a few gallons of Chevron with Techron , figuring it'll at least clean the injectors and the like.

Rather than contaminate old and new fuel, I figure I'll drain the tank and use the old stuff in the mower.

So I take my clear hose and squeeze-bulb lashup (I HATE the taste of hi-test, don't you?) and shove it down into the tank till I hear it bottom out,, position my catch can and give the bulb a couple of squeezes........and out comes about a cup and a half of water, debris and insect parts before I finally get fuel.................................

Put my fresh fuel in her, fired her up.......

...and I rode that bike for a year and a half before I sold her for almost twice what I paid.....


One shot deal, you say?

I don't normally do this (reveal what I pay for stuff) but, you know that RC51 I listed the other day? http://www.twowheelfix.com/showthread.php?t=11950, well, lets just say I bought it way under wholesale book, OK?

Well, I got it home (remember, I bought it as a non-runner; the former owner was sure it needed a new ECU, maybe a whole new wiring harness...his buddy is a mechanic and told him so, that's why he was selling it so cheap) opened up the tank, didn't hear any sloshing, so I poured a gallon of gas in, put it on the battery charger, turned the key, hit the starter and ....Vroooomm chuga chuga vroomm.........

Remember when your magic carpet won't fly....air, fuel,compression and spark.......do the simple/cheap/easy stuff first, starting with is the key on, in neutral and do you have gas...........ARE YOU SURE?




It's snowing here right now, so you folks in the warm areas suck..................

[marko138]

Snowing 90 miles north of you too, Leigh.

Good post. See you in the spring...

[Captain Morgan]

Good post. Had an ATV that I couldn't get to start for shit. Had fuel, cause I could hear it sloshing. It just didn't have enough fuel because the damn reserve switch was broken.

[Fleck750]

You hit right on the mark.

Most people are afraid of making a mistake, that's why mechanics stay in business. Too bad most of them aren't worth shit, though.

[smileyman]

My dad was a mechanic all his life, professionally for 35 yrs. We have stories like that which would last several bottles of scotch. Keep it simple stupid solves a ton o problems!