I have a 03 700 twin with carb .I had it out today and in high it would start to bogg down and backfire. It was not as bad in low or in neu. changed plugs still the same.I'm getting a new fuel and air filter tonite. Any other ideas thanks for the imput.

 

Welcome.

Check to see the airbox, especially the snorkle intake is not obstructed.

JIm

 

Check to see the ETC is properly adjusted too.

 

Look at the boot between the carb and the engine. My mounting bracket for the carb pulled out and mine did the same thing

 

Maxdad my sp700-02 did the same thing but my boot had a small split in it.And I didnt find it till I took the rubber boot off and looked at it real close.......

 

I caught my carb boot adaptor before it was cracked completely through so mine never ran bad, luckily i was looking things over.

I have had the foam around the snorkle get sucked up and run like that til i figured it out.

Jim