What happened to Mcelraths bike?

Skidaddle wrote:

Why does this not affect anything else with hot underhood temps of Black Cowled, in the heat of the summer Outboards, Enclosed spaces of snowmobiles, or...

Why does this not affect anything else with hot underhood temps of Black Cowled, in the heat of the summer Outboards, Enclosed spaces of snowmobiles, or cars.

And before you say its cold for snowmobiles, Um yah, it gets hot enough under there to melt wiring and other plastic parts without heat tape protection. Especially with all the vents taped off on powder days.

I'd like to see one of these guys shoot their throttle body or lines with an infrared temp gun and show us. Because I know for a fact the underhood temps of my sled is far hotter because I gun my clutches all the time and they are 2 inches away from my throttle bodies and get way hotter than the engine.

And I've used the same fuel. So I just don't buy it. It's not that hot.

yzf842 wrote:

It broke

johnnypotato123 wrote:

I don't believe boiled fuel, no way they ran 24 30 minute moto's in at least as hot weather as Dallas with no problems and then...

I don't believe boiled fuel, no way they ran 24 30 minute moto's in at least as hot weather as Dallas with no problems and then have a problem during a 15 minute supercross? No way.

Crazy to me that no one tried to find out what happened, I know it's a bit of a situation where you probably don't want to bother them right after but this isn't your local motocross race this was a professional losing a win and potentially a championship and we have no information on what happened.

86honda wrote:

I talked to one of the guys that could not finish the race last night because his fuel boiled. It was warm on the race track

Richard Hard wrote:

What a load of old cobblers,the ambieant temp has to be frigging high for that to happen

motokiwi wrote:

With all these electronics they are probably more susceptible to purposeful electronic interference.

Katoomey wrote:

I'm not gonna pretend like I know what happened to Shane's bike, but one would assume that if his fuel got too hot, then others would...

I'm not gonna pretend like I know what happened to Shane's bike, but one would assume that if his fuel got too hot, then others would have had that problem as well.

I will say this though...

Vapor lock on an EFI engine is way more likely to happen at the pump (located in the fuel tank), not at the fuel rail or injectors (pressurize fluids have a much higher boiling temp). On a sled, or car, the tank is mostly isolated from engine temps, and they have way more fuel to heat up (and of course a sled lives in much colder temps, so that is another factor in fuel tank temps). Motocross bikes have a small amount of fuel located right above all the heat.

that info is free...so you don't have to buy it.

86honda wrote:

Richard the fuel tank is above the motor. Where does heat go?

Jbulz wrote:

Bikes are too complicated? These EFI systems are barely more advanced than 1980s automotive technology... MX/SX is in the stone age compared to most other forms...

Bikes are too complicated? These EFI systems are barely more advanced than 1980s automotive technology... MX/SX is in the stone age compared to most other forms of motorsport. Yet we act like logging wheel speed and suspension motion is rocket science.

scrubbin627 wrote:

If we were talking about a production bike I would agree with you. However, I doubt factory KTM is running the stock engine management system on...

If we were talking about a production bike I would agree with you. However, I doubt factory KTM is running the stock engine management system on a max effort race engine like that. I could be wrong though.

When I built my race car (twin turbo 2013 Camaro) the first thing I had to do was replace factory EFI system with something far more complex (F.A.S.T. engine management) because it had 10x the adjustability. It also required more sensors to monitor the extra tables. More sensors means more systems to fail. I am just assuming the factorys do the same.

Skidaddle wrote:

All I can say my sleds underhood temps are Far hotter. And as mentioned its pressurized past the pump. He was what 8 laps in? Someone...

All I can say my sleds underhood temps are Far hotter.
And as mentioned its pressurized past the pump. He was what 8 laps in?

Someone go ride and shoot their throttle body with an infrared gun. If its 80 ambient, ill say 90 tops.

resetjet wrote:

Ok, I checked and the boiling temp of fuel will drop as pressure drops. So if my check valve is clogged, as I use gas, it...

Ok, I checked and the boiling temp of fuel will drop as pressure drops. So if my check valve is clogged, as I use gas, it creates a small vacuum in the tank. Not enough to kill the bike as the fuel pump can still suck against the vacuum, but enough to substantially lower the boiling point of my gas. Like I said, if you take the cap off, it stops in 5 seconds or so.....

This could be what happened to them, but who knows, it could be 1000 things.

resetjet wrote:

Ok, I checked and the boiling temp of fuel will drop as pressure drops. So if my check valve is clogged, as I use gas, it...

Ok, I checked and the boiling temp of fuel will drop as pressure drops. So if my check valve is clogged, as I use gas, it creates a small vacuum in the tank. Not enough to kill the bike as the fuel pump can still suck against the vacuum, but enough to substantially lower the boiling point of my gas. Like I said, if you take the cap off, it stops in 5 seconds or so.....

This could be what happened to them, but who knows, it could be 1000 things.

mx836 wrote:

There's a good chance it's your vent cap if you have one of those little aftermarket majobies. Put a hose on it and see what happens.

mx836 wrote:

So Shane boiled fuel in less than 10 minutes in a temperature controlled stadium? Why haven't they boiled fuel before?

mx836 wrote:

So Shane boiled fuel in less than 10 minutes in a temperature controlled stadium? Why haven't they boiled fuel before?

Katoomey wrote:

it's happened, believe it or not. They don't insulate fuel lines and the underside of fuel tanks with gold just to be wasteful. ....diamond encrusted 24k...

it's happened, believe it or not. They don't insulate fuel lines and the underside of fuel tanks with gold just to be wasteful. ....diamond encrusted 24k gold shark tanks yo!!!

again, for the record, I don't know why, claim to know why, or even care why Shane's bike took a shit...

resetjet wrote:

Ok, I checked and the boiling temp of fuel will drop as pressure drops. So if my check valve is clogged, as I use gas, it...

Ok, I checked and the boiling temp of fuel will drop as pressure drops. So if my check valve is clogged, as I use gas, it creates a small vacuum in the tank. Not enough to kill the bike as the fuel pump can still suck against the vacuum, but enough to substantially lower the boiling point of my gas. Like I said, if you take the cap off, it stops in 5 seconds or so.....

This could be what happened to them, but who knows, it could be 1000 things.

Katoomey wrote:

ok...lets start over. under hood temps don't matter unless the fuel tank is right on top of that heat. this is all that really matters in...

ok...lets start over.

under hood temps don't matter unless the fuel tank is right on top of that heat. this is all that really matters in relation to this conversation.

the throttle bodies don't carry any fuel- just air... so who cares how hot they are? the fuel rail and lines carry it to the injector. Again, these lines are pressurized and require much more heat to vaporize the fuel. This is not a concern, and why vaporlock has almost all but gone away with the advent of EFI, because there is no longer non-pressurized fuel near the engine compartment, like there was with carbureted vehicles, including motorcycles.

Of course the fuel is pressurized after the pump. The pump is what's pressurizing it!!! ..and what does that have to do with what lap he was on, I dont get that part?

The point is. the only fuel susceptible (for the most part) to vaporizing is the non-pressurized fuel in the tank, which causes the fuel pump to starve, or cavitate. You do know that fuel pumps are in the tank, yeah?

anyway, thats the difference between your snowmobile, or car.... the non-pressurized fuel in the tank is not sitting right on top of the motor (heat source), and it's a much smaller amount of fuel. hell, in a car it's 6 feet away...on a dirt bike its centimeters away, right above it (do I have to remind you that heat rises?).

Dirbikes will absolutely boil fuel. I've seen it myself. But, I'm not saying for one second that's what happened to Shane's bike, I'm just saying its absolutely plausible.

Katoomey wrote:

ok...lets start over. under hood temps don't matter unless the fuel tank is right on top of that heat. this is all that really matters in...

ok...lets start over.

under hood temps don't matter unless the fuel tank is right on top of that heat. this is all that really matters in relation to this conversation.

the throttle bodies don't carry any fuel- just air... so who cares how hot they are? the fuel rail and lines carry it to the injector. Again, these lines are pressurized and require much more heat to vaporize the fuel. This is not a concern, and why vaporlock has almost all but gone away with the advent of EFI, because there is no longer non-pressurized fuel near the engine compartment, like there was with carbureted vehicles, including motorcycles.

Of course the fuel is pressurized after the pump. The pump is what's pressurizing it!!! ..and what does that have to do with what lap he was on, I dont get that part?

The point is. the only fuel susceptible (for the most part) to vaporizing is the non-pressurized fuel in the tank, which causes the fuel pump to starve, or cavitate. You do know that fuel pumps are in the tank, yeah?

anyway, thats the difference between your snowmobile, or car.... the non-pressurized fuel in the tank is not sitting right on top of the motor (heat source), and it's a much smaller amount of fuel. hell, in a car it's 6 feet away...on a dirt bike its centimeters away, right above it (do I have to remind you that heat rises?).

Dirbikes will absolutely boil fuel. I've seen it myself. But, I'm not saying for one second that's what happened to Shane's bike, I'm just saying its absolutely plausible.

smoothies862 wrote:

ralph= so fro.if I run around a small square for 15 minutes. I will be more tired than running around a large square for 15 minutes...

ralph= so fro.if I run around a small square for 15 minutes. I will be more tired than running around a large square for 15 minutes?
fro=yeah,ralph. it will be a longer run. it will be magnified if the square is deteriorating.how bad do you want it?!
ralph=what if the whoop pad is longer? do the candles burn longer?
fro=lets send this down to rc.
rc=whoever has the advantage in the whoop pad, will be benefited.
ralp=..........(checking the tour dates for rush)
fro=monster energy supercross!!!!!!
fro/ralph in unison=QUAD! QUAD!
jenny=I asked this dog how he "feels" about this show. he told he feels dog gon' good.back to you guys
art and david=*holding hands jump off a bridge and land on weege*.....

mx836 wrote:

I don't buy the boiled fuel thing for half a second. I'm not claiming to be a fuel expert, but I ain't buying it.

resetjet wrote:

Ok, I checked and the boiling temp of fuel will drop as pressure drops. So if my check valve is clogged, as I use gas, it...

Ok, I checked and the boiling temp of fuel will drop as pressure drops. So if my check valve is clogged, as I use gas, it creates a small vacuum in the tank. Not enough to kill the bike as the fuel pump can still suck against the vacuum, but enough to substantially lower the boiling point of my gas. Like I said, if you take the cap off, it stops in 5 seconds or so.....

This could be what happened to them, but who knows, it could be 1000 things.

mx836 wrote:

There's a good chance it's your vent cap if you have one of those little aftermarket majobies. Put a hose on it and see what happens.

Knarfious wrote:

Also take the cap off and take the hose off, put the little nipple output to your lips and try and suck and blow. If air...

Also take the cap off and take the hose off, put the little nipple output to your lips and try and suck and blow. If air doesn't come through its not venting properly. Take apart the cap with the screws on the orange part underneath, there's a little ball in there, clean it thoroughly with contact cleaner or brake cleaner and re-assemble making sure you don't torque the screws too much as that sometimes causes the issue to begin with.

Motofinne wrote:

These guys jacked with his bike. [img]https://p.vitalmx.com/photos/forums/2017/02/13/176318/s1200_e9d8d2cf4d5e7f6c35f1c2b7e0e7678c.jpg[/img]

These guys jacked with his bike.