400ex carb for 350x - She's A Runner!

[userj8670]

Bought an '07 400ex carb for my 350x. I have seen a 300ex intake is able to be used as well with the 400ex carb. Since I have searched and can't find an answer can someone please tell me if it's bigger than stock 350x intake?

I am aware you need to stretch the stock boots over the larger 400ex carb - but if I can find an intake that's bolt on and bigger I'd prefer to go that route...

[oldskool83]

when i had my 350x the intake was not a bolt on with the 400ex carb. I'd use a 400ex one for many reasons.

[userj8670]

when i had my 350x the intake was not a bolt on with the 400ex carb. I'd use a 400ex one for many reasons.

Thanks so much for the reply! I was hoping somebody would chime in.

I did look into the 400ex intake, however the only ones I seen were a 3 bolt pattern and the 350x head is 2 bolt pattern? Is there a a swap of some sort?

[shortline10]

I just did a 2007 400ex carb swap a week ago , about 30 seconds with the heat gun and the 400ex carb slid on the factory 350x manifold with no issues , same with the boot to air box , also the factory snorkel will need to be heated up right were the choke lever pivots for clearance .
Great mod .

[userj8670]

I just did a 2007 400ex carb swap a week ago , about 30 seconds with the heat gun and the 400ex carb slid on the factory 350x manifold with no issues , same with the boot to air box , also the factory snorkel will need to be heated up right were the choke lever pivots for clearance .
Great mod .

Thanks for the reply Shotline! Did you have to mess with the jetting or the accelerator pump?

[shortline10]

The 400ex stock jetting was spot on .

[userj8670]

Any tinkering with the accelerator pump?

[RIDE-RED 250r]

The 400ex stock jetting was spot on .

A friend of mine who is a member here bust doesn't post much came to the same conclusion with the jetting.

[shortline10]

Nope , factory setting was perfect , hit the throttle as fast as I could and no hesitation !

Any tinkering with the accelerator pump?

[userj8670]

Impressive! I am throwing mine on Saturday so we shall see how it goes. I am praying and hoping I don't need to tinker and it's just bolt and go. I bought a bunch of jets just incase. I will keep you posted

[DickyDanger]

Impressive! I am throwing mine on Saturday so we shall see how it goes. I am praying and hoping I don't need to tinker and it's just bolt and go. I bought a bunch of jets just incase. I will keep you posted

any updates userj8670?

[userj8670]

any updates userj8670?

Unfortunately no - ran out of time. Got the carb in and man its a tight fit. Had to take the intake off and the put the carb on the intake and then screw the intake in which with an open end wrench was 1/8th turn at a time...but it's on!

[shortline10]

Get this going yet ?

[userj8670]

Get this going yet ?

Hey Shortline - thanks for remembering and showing interest! Unfortunately no I have no updates since last. Problem is that the bike is at Hondaline Hartmans which is 2 hours away from where I reside. Trying not to take up every weekend from his wife and kids but maybe this weekend. I promise this will be updated as soon as I have an update - will more than likely need your vast knowledge of engines to help me get this carb dialed in!

Thanks again!

[userj8670]

I just did a 2007 400ex carb swap a week ago , about 30 seconds with the heat gun and the 400ex carb slid on the factory 350x manifold with no issues , same with the boot to air box , also the factory snorkel will need to be heated up right were the choke lever pivots for clearance .
Great mod .

Forgot to ask you - how did you specifically install the carb into the intake boot. For me I had to take the intake boot off to grt the carb into the frame. Then once in the frame I put the intake on the carb and installed the 2 bolts thar mount the intake to the head. Problem was that since the carb is so big I could barely get a box wrench in there to tighten the bolts. 1/8th of a turn at a time - sure hope I don't have to mess with jetting much and go thru that every time