Bogs at full throttle.

[Norcorider44]

Hello my friends i am very new to this so bare with me. I just got a 1995 xp 720 and it starts great and takes off like a rocket but at full throttle it bogs and i have to let off the throttle to pick up speed again. Could this be a carb issue. All the gas lines have already been changed from the gray lines they used. If the carbs didnt get cleaned after the lines get changed could the carbs still be clogged. Any help would be appreciated.

 

[mikidymac]

Yes, you are starving for fuel and will ruin your engine if you keep running it that way.
Carbs need to be rebuilt correctly with only Genuine Mikuni parts, fuel strainer and selector need to be checked for air leaks or just replaced.

 

[Norcorider44]

Thank you for the info. I will rebuild the carbs and replace the fuel strainer.

 

[mikidymac]

The fuel selector is typically bad also. Remember only OEM parts on the fuel system.

 

[Norcorider44]

Can i delete the fuel selector. Would that cause me problems?

 

[mikidymac]

You can bypass it for testing.
I like having Reserve for emergencies and the ability to turn the fuel off when not in use.

 

[JeremyD615]

Can i delete the fuel selector. Would that cause me problems?

You could bypass it, and it won’t cause problems until you run out of gas... Having that reserve comes in really handy, especially with how often the fuel gauges fail in these things! The selectors are inexpensive, so I’d just replace it.

 

[Norcorider44]

Ok perfect. I will replace it with oem parts and i will keep you posted. Any other info on these machines would be great. Thank you all for the help. Great community here

 

[mikidymac]

THey are really pretty simple. Clean fuel system, correct API-TC oil and they run really well.

 

[Norcorider44]

I had another quastion about the vts. Mine does not seem to be working. Is this common on these machines and how important is the vts.

 

[mikidymac]

It's very common. It isn't really necessary but nice to have working.
If it isn't working then unplug all connectors to it because it can fry your MPEM.

 

[Norcorider44]

Im sorry im so new i wouldnt know where to look to unplug any connections to it. Is this something i can get to easy? Thanks again for any help

 

[Norcorider44]

So i was taking a look at the seadoo today and i can smell fuel so when i checked the lines i found that there are 2 sets of fuel lines. One line comes straight out of the fuel tank and goes to my carbs. The other line comes from the selector to a fuel filter then goes to what looks to me like the block. Again im new lol. So the line that goes to the block had a very shitty clamp on it that was broken. Fuel was leaking from this spot. Could this maybe have caused my bog at full throttle. Thanks again for any help
(The pictures are the broken clamp)

 

[Norcorider44]

I also found the vts and unplugged all wires going to it. Thanks for the advice about that. You guys are great.

 

[mikidymac]

Yes that fuel leak was probably sucking air at WOT. A fuel leak can also cause a very dangerous explosion.

 

[Norcorider44]

Would anyone know why there would be 2 sets of fuel lines. One set goes to the carbs and the other line that was leaking looks like it goes to a spot just under the carbs. Is the line on top going to the carbs for low speed and idle. And the other line that goes underneath is that for high speed full throttle? I could take some pics if that helps. Also i fixed the fuel leak with a new clamp. Fingers crossed that was the reason she bogged at WOT.

 

[Sportster-2001-951C-Stock]

There's a fuel return to the tank from the carburetors.

 

[Norcorider44]

Would that return be the top line that splits off into both the carbs. The other line that comes from the fuel selector to the fuel filter then to just under the carbs. Is that the fuel in line?

There's a fuel return to the tank from the carburetors.

 

[mikidymac]

The fuel from the tank goes through the selector and strainer then into the carbs. The excess fuel that the engine can't use is fed through the return line directly back into the tank.

The top of the fuel tank where the hosed connect id actually labeled on the side. VNT=vent, ON=on, RES=reserve, RET=return.

 

[Norcorider44]

Well guys i fixed the bog. It turns out it was just the fuel selector. As well as that broken clamp. It no longer bogs at WOT and runs really good. I cant thank you guys enough for all your help and i will tale pics soon. Cheers guys.