Seat Fire...Listen up!!

[smokeless1]

When Carbs Ice it's not in the float bowl. This sled deosn't have an ecletric pump either. The bowls are filled by pulses pulled on the pumps by the clinders. I do not beleive the float was stuck open and it kept filling with fuel


I think he had a fowled plug. It filled the exhaust with raw fuel and when it got hot enough boom. the sparks were from peices of the seat melting off.

I've seen a Venture do this. It lost a cylinder and the guy didn't know it. He was rideing like 10 to 20 MPH. He thought it was loading up so he ignored it. the silencer filled with fuel and when it got hot enough Boom it went up in flames. it took snow and bottles of water to get it out!!!!!!!!!!

Ventures have mufflers under the seat??

 

[smokeless1]

Carb Icing is usally a result of mosture in the air I would think that if one carbed iced all three would have iced.

They would. This would cause the sled to run really badly. Not as it did.

And as far as fuel heater shut offs, if these machines iced up as you speculate, and say 10 guys out of the dozens and dozens that have put the carb heat coolant shut offs on and shut them off COMPLETELY, we would have heard lots of guys with this trouble already, since these shut offs are not new.

As for contaminants in the gas, it was 9:30 at night, and this place is not getting fuel dumped anywhere near that hour, and I got gas with the same hose from the same pump at the same time. I would buy that since it was snowing that there could have had a couple specks of snow flew into the tank over the few minutes the cap was off, but that is it. We fueled up 4 sleds all at the same time from the same hose, and we should all have had troubles had the pump with a filter on it, pumped out sediment from the bottom, or water in the gas, which hardly ever happens anymore with alcohol added to everything these days.

Nope got to dig deeper here. Carb heated by antifreeze isn't it, or fuel contaminents either. Stuck float, I buy, but only one and not continueous because if it was stuck open the machine would have gone down to 3 cylinders completely, and that wasn't happening. Excessive fuel into the carb would cause the spark plug to miss, occassionally, and is the likely culprit, but it was not because of bad fuel, or bad plug.

Dealer has not been able to duplicate this at the shop as of today either, so whatever it was happens intermittently enough to stymie them too.

 

[LazyBastard]

Stuck float, I buy, but only one and not continueous because if it was stuck open the machine would have gone down to 3 cylinders completely, and that wasn't happening. Excessive fuel into the carb would cause the spark plug to miss, occassionally, and is the likely culprit, but it was not because of bad fuel, or bad plug.

How do you know it wasn't completely on 3? You weren't going fast enough to tell.

If there was a bit of water in the gas that got sucked into the carb(s), then you could have had ice plug one and not the others, probably the last carb on the heater line. Coolant goes through one carb into the next, so each carb gets progressively cooler.

As for sporadic problems... How many *FORD EXPLORERS* had tires explode? And that was unmodified. The frequency was VERY VERY low with respect to the number of units produced.

Another example; 03RX had weak control rods, some of which broke. How many broke? 1 in 100? Again, STOCK. What proportion of all RX1's have coolant shutoffs? Probably under 1%. And if 1% of sleds with coolant shutoffs subsequently burst into flames, thats 1 in 10000 overall. How many RX1's were built? Just because a particular MODIFICATION doesn't kill everybody doesn't mean that it CAN'T. For you, the conditions were just right. The unlikely event that the wrong amount of water was in the last place you wanted it, combined with the coolant being shut off, and the fact that you were driving slowly enough that you wouldn't notice that its only running on 3 cyls.



RX1 is perfectly safe. Don't try blaming your damage on the machine when it was caused by a modification.

 

[E Z ED]

First post here so have patience.
New 2004 Warrior with 300 kms. on it and I notice every time I shut it off
it backfires as if burning fuel in the exhaust. If you think yamaha will warranty it or admit that they have a problem think again. I brought up the track ratcheting with my dealer and they played dumb because they don't want to do any recalls or admit to a problem. As far as having 1 cylinder not working correctly I can't wait to have all four up and running.
Yamaha break in procedure sure sucks because I just can't keep out of the throttle.
Have a nice day
Edge

 

[kviper]

I am not saying that this is your problem but may be somthing you may want to think about. Myself and two friend's all bought Vector's, they were all delivered in August with three gal of gas and stabel, I filled mine up with gas when i brought it home because a full tank will not detereorate as fast as a lower level (air space) will. When i took mine for the first ride ( 1/4 Mi) it ran ok but sluggish. I siphoned all of the gas out and put in fresh and WOW what a diff. The second sled did not add any gas to the three gallons and would not idel. We drained and added fresh and it ran perfict. About three week's later all three of us went north for a ride, The third sled was unloaded and barley made it to the pump's, After he filled up we picked up the back of the sled to try to run it to get fresh gas in to the carb's and with in only second's with the poping and backfiring the whole back side of my glove was melted. The sled was only run frome the trailer to the pump's and shut off. Even if you shut the gas off there is still gas in the float bowl's unles you took the plugs out and drained them. It would have taken at least a mile to get fresh gas through the lines and fill the carb's. Old gas is very hard on plug's and you may have been getting a very poor burn (poping, Backfiring etc) causing the fuel and air mix to burn in the exhaust. I alway's fill the sled full before i store, Run it till it is good and warm to evaporate all moisture about once a month and siphon and refill with fresh before first ride and i have never had any kind of problem's with tarnish or moisture. Just a few thought's. kviper

 

[jtssrx]

I will say this I've trailered our RX-1's with 1 gallon to 10 and never had a problem "Knock on Wood"!!!!!!


Now i do have a nice big 4 place trailer. all we do is set the parking brake and they never move. Are these sleds trailered on 2 place trailers that move a lot???

 

[smokeless1]

I will say this I've trailered our RX-1's with 1 gallon to 10 and never had a problem "Knock on Wood"!!!!!!


Now i do have a nice big 4 place trailer. all we do is set the parking brake and they never move. Are these sleds trailered on 2 place trailers that move a lot???

Not on two place trailer, but in cargo trailers with full enclosures and power solar ventilation so in the sumer with the sun out, the temp is equal to the outside. The gas in this sled was 90% new. We just left the gas pumps and before leaving the trailer, we added a gallon or two to make sure we would not have a problem. Both this sled and mine have been started occassionally all summer and fall long.

When we left the trailer, the machine ran fine. No missing, popping or indication whatsoever that there was about to be a problem. Most certainly the fresh new gas was pumping by the time we got a mile down the road.

I am inclined to think that something held the float open, and caused excessive fuel to flow rather quickly thru the engine, and into the exhaust system. This then flooded one cylinder and caused the accumulation of fuel in the exhaust pipe and muffler.

LB- you have to be pretty lame not to tell if you are running on 3 cylinders instead of 4. Throttle response would be gone. Cylinder would not be firing and you kinda miss the horses. And the coolant control to the carb was NOT SHUT OFF. It was set to 7/8 where it has been on mine and since my sled should basically have been a control, with exactly the same proceedures thru summer and fall and at start up, why didn't mine do the same thing? Do you know how many sleds out there run with no heated carbs?? This is a new design to keep the fuel at an even temperature and to be able to keep a steady carb adjustment. But only about 100,000 other sleds out there have none. If you say that the temps drop by factors because of expanding gases, I loose you. This would happen on all engines and of course it does not. Heated carbs allow for more process jetting to get leaner burns for epa, and steady performances out of those carbs. You idea that the carb will drop the temp of the gas to -100 degrees is not happening; and certainly isn't happening in one or two miles.

I believe the float simply stuck open, pumping fuel within seconds into the exhaust pipe and muffler and in less than one minute the whole thing happend. That is my take. And my analysis of what happend.

If that happened to his sled, in such a short time, it could happen to anyone one of yours as well. I hope it doesn't but I sincerely believe it could. Time will tell for sure.

 

[LazyBastard]

LB- you have to be pretty lame not to tell if you are running on 3 cylinders instead of 4. Throttle response would be gone. Cylinder would not be firing and you kinda miss the horses.

They actually run pretty good on 3 cyls at low speeds like you were traveling - its not like a 2-stroke twin where you loose 50%, on this you only loose 25%.

And the coolant control to the carb was NOT SHUT OFF. It was set to 7/8 where it has been on mine and since my sled should basically have been a control,

Low enough that it wasn't heating the last carb in the line.

with exactly the same proceedures thru summer and fall and at start up, why didn't mine do the same thing?

Because you didn't have WATER in your float bowl.

Do you know how many sleds out there run with no heated carbs?? This is a new design to keep the fuel at an even temperature and to be able to keep a steady carb adjustment. But only about 100,000 other sleds out there have none.

Yamaha's been heating carbs since the 80's. How many 4-cyl engines don't have heated carbs? With twins, one carb goes and it runs real bad - won't even engage clutch usually. Also tends to cause the engine to BURN DOWN <-- this is a well known event.

If you say that the temps drop by factors because of expanding gases, I loose you. This would happen on all engines and of course it does not.

It does happen on all engines and yes it does happen. EVERY engine. EVERY time that gas expands. Take a nice warm air tank (one thats pumped to a nice high pressure, like a dive tank), and open the vent towards your hand. You will notice that it is COLD that comes out.

Heated carbs allow for more process jetting to get leaner burns for epa, and steady performances out of those carbs. You idea that the carb will drop the temp of the gas to -100 degrees is not happening; and certainly isn't happening in one or two miles.

Then I challenge you to put a thermometer into your carb and go for a drive. The reason that carb heaters are used on... pretty much ALL 2-strokes... is because a frozen carb can cause the engine to BURN DOWN INTERNALLY.

I believe the float simply stuck open, pumping fuel within seconds into the exhaust pipe and muffler and in less than one minute the whole thing happend. That is my take. And my analysis of what happend.

Yes, but only because there was ice caused by having NO CARB HEATERS.

 

[smokeless1]

Yes, but only because there was ice caused by having NO CARB HEATERS.[/quote]

Well, as I said, time will tell. If it happens again, or to even you, be sure and tell us will you?? Fella from the U.P. had 60 miles on his and no carb coolant restricters. Maybe he was just "unlucky" too.

Nobody else with carb coolant restricters have burned up yet, have they?? I am thinking it is something else. And if I am right, we WILL see this again, and again and again, til cheap yamaha fixes it of worse somebody dies, and they recall all of them.

 

[ReX]

I wasn't going to get involved, but the reality is that any engine running in just the wrong way can dump fuel into the exhaust and it can burn there - turning the exhaust bright red, even white.

In over 20 years of building cars, trucks and 27 years of sledding I've seen this sort of thing many times.

I've had/seen floor carpets catch on fire in cars, undercoating catch on fire on trucks, melted hoods on sleds, etc. Many cars have burnt to the ground from glowing exhaust systems.

With the RX-1, if the exhaust gets this hot, the seat burns.

It did concern me a little, but not enough to stop buying an 05 RX-1 ER. Even with a badly running engine it's probably less than 1 in a 10,000 that the exhaust lights up like this. Keep the motor running well and the chances are very, very slim.

I don't think it really matters exactly what caused it, nor do I think it's possible to figure out over the internet. Could be stuck needle and seat, carb icing, bad spark plug, or any of many other problems.

Anyway - I'm going sledding on my RX-1 and yes, we will see this again...but not very often.

My plan - if my sled is misfiring and my #*$&@ is getting hot and/or I smell burnt plastic I'll stop and check it out, otherwise I'm sledding. I would be surprized if someone dies from this. More likely in a car (young kids trapped in back seat, can't open door, etc.).

 

[Sled Dog]

I got fire insurance if mine lights up I am putting it out with gas.

 

[ken_climb]

Barretts yamaha in Fruitvale BC had this happen to them,It was because they had leaned out the carbs way to much and caught the seat on fire.

 

[Superglide Sport]

Running too rich.......................

It's what happens when the choke is partially on. I bet his choke was causing the rich mixture, causing the plugs to foul, misfire and dump raw fuel into the muffler. These 4 stroke don't need much choke at all and aren't very cold blooded.

Make sure the choke is fully "off" when riding.

Best,

 

[Superglide Sport]

Running too rich.......................

It's what happens when the choke is partially on. I bet his choke was causing the rich mixture, causing the plugs to foul, misfire and dump raw fuel into the muffler. These 4 stroke don't need much choke at all and aren't very cold blooded.

Make sure the choke is fully "off" when riding.

Best,

 

[smokeless1]

Re: Running too rich.......................

It's what happens when the choke is partially on. I bet his choke was causing the rich mixture, causing the plugs to foul, misfire and dump raw fuel into the muffler. These 4 stroke don't need much choke at all and aren't very cold blooded.

Make sure the choke is fully "off" when riding.

Best,

Nether his sled or mine will run at all with the choke left on, even partially. They choke up and quit on you fast. Besides the fast idle will force you to shut it down. Got to be something else.