Yamaha's response to "Hard Start"

TXTenere

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It seems that there's some sort of consensus that the hard start is due to flooding. If that's so, it's strange to me, because many report a "normal" shutdown, and then the bike sits for a few weeks. They come out to the garage, try to start it, and the bike doesn't start. They crank and crank, and eventually the bike starts. So, at what point did the motor flood?

Based on the info in this thread about turning the key is not putting fuel into the motor, and only fuel being put into the motor when the starter is running, the only time that the motor could be flooding is during the cranking process, which is "after" (or more accurately, during) the hard start. If all this is so, it would indicate that the hard start is a separate issue and is not a result of flooding. Yes?
 

yz454

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Like I have said rider error . As of over heating never heard of an s10 boiling over . Even in the summer down in the bottom of a canyon on single track riding double and clutching a lot , fan comes on and goes off what more do you want .
 

autoteach

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in my car there is a gauge with a red zone and a not red zone. It never goes in the red zone. My super gets up around 210 degrees or higher. Red is hot, 210 is hot, therefor the super runs in the red all the time. ::017::
 

markjenn

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SPX said:
It seems that there's some sort of consensus that the hard start is due to flooding. If that's so, it's strange to me, because many report a "normal" shutdown, and then the bike sits for a few weeks. They come out to the garage, try to start it, and the bike doesn't start. They crank and crank, and eventually the bike starts. So, at what point did the motor flood?

Based on the info in this thread about turning the key is not putting fuel into the motor, and only fuel being put into the motor when the starter is running, the only time that the motor could be flooding is during the cranking process, which is "after" (or more accurately, during) the hard start. If all this is so, it would indicate that the hard start is a separate issue and is not a result of flooding. Yes?
The motor floods during the initial attempt to start. For some reason (which is currently unknown) the FI system delivers too much fuel during the start attempt. Once the motor starts to flood, continued cranking just delivers more and more fuel and since there is no combustion removing it, the flooding condition gets worse the longer you crank. The only way to solve the problem is to cut off the fuel and open the throttle plates to deliver air without fuel. If you crank long enough like this, the A/F ratio will drop back into the combustible zone and the engine will start.

WOT is the first thing to try as most FI systems recognize WOT during starting as the operator saying the motor is flooded since WOT was the way you started a carbed motor that was flooded. The system is supposed to open the throttle plates and cut off fuel. (There is some evidence that the plates don't open very fully and this is why you have to sometimes crank for a long, long time to clear the flooded condition.) WOT probably cuts off fuel on its own, but there are some who have had better luck with pulling the fuel pump fuse which is a sure-fire way to cut fuel.

AFAIK, just continuing to crank with the throttle closed will never cause a flooded motor to start. It just digs the hole deeper. Some have abandoned the bike, charged the battery, and gotten it to start the next day with normal starting technique but that's probably the combo of letting the fuel evaporate overnight and starting off with a nice hot battery.

Why does the FI system occasionally flood the motor during starting for no apparent reason? That's the big mystery that has been discussed for literally thousands of posts. Previous key cycling and previous interrupted warm-ups are definitely contributing factors but they don't definitively cause the problem. (My theory is that both contribute to a weaker battery and slightly fouled plugs and these things are sometimes the straw the breaks the camel's back on a bike that is already at the ragged edge of proper starting mixture. And I don't think our starter speed, size of starter, and battery size does the bike any favors.)

- Mark
 

autoteach

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Sarcasm...totally wasted here. Why am I doing this? Bored with the "hardstart". Also, there are to many people ramming the conjecture hardon into the topic and not paying any attention to the science. They wont read the posts covering the how and why and the solution, and now we have some jack wagons talking about inadequate cooling... something that I have seen on every single motorcycle forum. Why? because the fan comes on. Christ, its doing its job and the thing turns off, meaning it got done with its job. So, I will see if someone acting as an ignoramus (me) can make a problem from nothing. So, back to the conversation... Dear God!! 210? Water boils at 212!! How on earth are they going to stop that from happening if it gets hot outside?!
 

yz454

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For some buddy that is so smart you have no idea how cooling systems .Please don,t tell me you work at something important.
 

tc9988

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autoteach said:
Sarcasm...totally wasted here. Why am I doing this? Bored with the "hardstart". Also, there are to many people ramming the conjecture hardon into the topic and not paying any attention to the science. They wont read the posts covering the how and why and the solution, and now we have some jack wagons talking about inadequate cooling... something that I have seen on every single motorcycle forum. Why? because the fan comes on. Christ, its doing its job and the thing turns off, meaning it got done with its job. So, I will see if someone acting as an ignoramus (me) can make a problem from nothing. So, back to the conversation... Dear God!! 210? Water boils at 212!! How on earth are they going to stop that from happening if it gets hot outside?!
at sea level a 15psi pressurized system with 50/50 water/ethylene glycol mix the boiling point is 265F. Probably won't appease the worry bead riders. I got your sarcasm ;)
 

snakebitten

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markjenn said:
The motor floods during the initial attempt to start. For some reason (which is currently unknown) the FI system delivers too much fuel during the start attempt.

<snip>
- Mark
Really, this is all that really matters on this 3 year+ debate. It's a fact. Undeniable. (although nothing is undeniable by our species)

However, no matter how many posts there have been, I still don't consider this a serious issue. It only seeeeeems like one because it's a Super Tenere that we are talking about. Everybody's spokes are now tight. Everybody's headlight wiring harness has been upgraded. :)
 

Maxified

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Did the dealer have any details about the hard starting problem for you? Hope the issue does not return for you like it has been reported by some.
 

autoteach

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yz454 said:
For some buddy that is so smart you have no idea how cooling systems .Please don,t tell me you work at something important.
awe come on, I understands perfectly why and how it works. I guess the question might be why would they want to keep the engine so hot?
 

Koinz

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autoteach said:
awe come on, I understands perfectly why and how it works. I guess the question might be why would they want to keep the engine so hot?
Mostly for emissions

The thermostat opens way cooler though. At cruising speed my temps are typically between 167-180. It's only in stop and go traffic that it ever kicks on the fan at 221
 

tubebender

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autoteach said:
I guess the question might be why would they want to keep the engine so hot?
Well, I know I'm not helping, and this thread has take a sharp left turn, but I'll play!

Gotta keep the stim alive!



(Jake Holman) This is the boiler. lnside belongs live steam. Savvy?
(Jake Holman) Strong steam.

(Po-Han) Stim.

(Jake Holman) Steam.

(Po-Han) Stim.

(Jake Holman) Live stim goes through this pipe. Live stim goes into the feed pump.

(Po-Han) Live stim! Make pump go vroom, vroom, vroom, vroom, vroom...

(Jake Holman) Live stim, huh?

(Po-Han) Live stim... Live stim... Live stim.

(Jake Holman) Exhaust stim.

(Jake Holman) Condenser. Makee steam all dead. You know, sleepy stim.

Po-Han) Live stim, dead stim.

(Jake Holman) Before, live stim. Now water. Water belong dead stim. All same dead stim.

(Po-Han) Stim dead. Stim dead!

(Jake Holman) That's right. That's it. Now you got it! That's right! That's the way it works!

And that's the throttle. l'll teach you about that throttle one day. Go ahead. Grab ahold of it.

Boo!

Nah. There ain't no ghosts in that engine.

(Excerpt from The Sand Pebbles, 1966, Steve McQueen (Jake Holman), Mako (Po-Han))
 
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