Vmax bogs down under load

[vmax bogs down when under]

Hi my 1990 vmax bogs down under load starts runs fine.have replaced all carb parts Inc new jets. New fuel pump.any help would be gratefull.

 

[one2dmax]

Are you testing with the airbox and other parts all in place?

 

[vmax bogs down when under]

Yes.

 

[MaxMidnight]

Is this a new bike to you; a problem that has developed since you owned it; a problem since you 'fixed' something?
Can we assume that the air and fuel filters have been changed within living memory?

When you say bogs down under load at what revs does this happen; does it occur with slow throttle opening or rapid?

 

[vmax bogs down when under]

The bike has been with a garage for ten months its 1990 brought it a year ago road it 30 miles.all the insides of the carbs have been replaced with new parts.new fuel pump.air box is not the problem.new air filter new pipes new regulator the list goes on it starts and runs fine just wont pick up when pulling away.

 

[MaxMidnight]

Have you checked the carb diaphragms lift as you open the throttle?

 

[vmax bogs down when under]

Yes they all new

 

[Fire-medic]

Check for a vacuum leak or leaks: carb boots from the airbox to carburetor bellmouths, or bottom of carbs to VBoost ass'y, or VBoost ass'y to cyl intake. Spray areas w/starting fluid, & see if rev's temporarily pick-up.

 

[user 16790]

are all the parts you have replaced been genuine or aftermarket, I've read that some aftermarket carb spares are not very good, are the new jets the same size, is your choke stuck on

 

[MaxMidnight]

Yes they all new

But can you see them rise when you open the throttle?