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07YZ450 Bog?

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Today at the track my bike would bog every now and then. It did it 1 in 3 times over this one jump. The jump was about 70ft to a flatland so I would be on the gas hard for the landing, soon as the bike touched down it did a big bog, then picked right up. What would cause that? I'm assuming it has something to do with the harsh landing.

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Today at the track my bike would bog every now and then. It did it 1 in 3 times over this one jump. The jump was about 70ft to a flatland so I would be on the gas hard for the landing, soon as the bike touched down it did a big bog, then picked right up. What would cause that? I'm assuming it has something to do with the harsh landing.

Most of the time, the harsh impact causes the fuel to evacuate the baffled area around the jets, allowing air to temporarily reach the main and pilot jet.

This area has been completely redesigned in the R&D Power Bowl, not allowing the air to reach the jets, no more hard impact bog. :thumbsup:

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Most of the time, the harsh impact causes the fuel to evacuate the baffled area around the jets, allowing air to temporarily reach the main and pilot jet.

This area has been completely redesigned in the R&D Power Bowl, not allowing the air to reach the jets, no more hard impact bog. :thumbsup:

How much are those? Not sure if I should need it though.. I hit this same jump many times on my 06 without the problem :excuseme:

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How much are those? Not sure if I should need it though.. I hit this same jump many times on my 06 without the problem :excuseme:

The R&D Power Bowl is actually a kit, the total cost is $249.95 Depending on how hard you ride, you may or may not need all the features that are included in the kit. It's like an insurance policy, we pay for them but

hope we never need to use them. If this device save just one trip to the emergency room, it is well worth it.

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I hit this same jump many times on my 06 without the problem :excuseme:

You may want to check the float height? Or, maybe the float is getting snagged a bit?

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You may want to check the float height? Or, maybe the float is getting snagged a bit?

I was thinking float height myself.. but being a new bike I would think Yamaha would have that set up properly :excuseme:

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I was thinking float height myself.. but being a new bike I would think Yamaha would have that set up properly :excuseme:

yea maybe....but worth checking eh?

Dean is dead on to.......R&D 249.00

And while your at it....ZipTy can help you with the float and the AP wire mod.....and more....125.00

Just comes down to how much you want out of the carb and what amt of $$$ this is worth to you.....to have a carb totally tuned and set up for maximum power, fuel flow and throttle response and no bogging period end....:excuseme:

You will be amazed at how different your bike will be doing this...as many of us have done and will do for every bike we buy....:thumbsup:

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I had the same problem. It was vapor lock. I pulled the gas tank vent and lost about 20-30 psi of pressure out of the tank. The problem went away.

May not be your problem, but is something to rule out as it is a cheap and simple fix.

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I had the same problem. It was vapor lock. I pulled the gas tank vent and lost about 20-30 psi of pressure out of the tank. The problem went away.

May not be your problem, but is something to rule out as it is a cheap and simple fix.

''

agreed and float bowl height setting is free to.....

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I had the same problem. It was vapor lock. I pulled the gas tank vent and lost about 20-30 psi of pressure out of the tank. The problem went away.

Yeah, good point. I read somewhere that the Pros don't use one way valves in their vent tubes to prevent that ever happening. I ditched mine too.

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The 07 doesn't have an inline vent tube.... so that cant be it.

My 07 YZ450F had the inline vent and I removed it the first ride. I ordered a R and D power bowl today, I'll give a race report next weekend.

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I'm not sure if the '07's are the same, but my '06 cap also has an inbuilt vent system that is easily "deactivated" by removing three screws and a plastic part. You may want to try that.

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