Yamaha razz choke and throttle problem

[spartan-spree]

I have a 1999 Yamaha razz and it only drives if you hold the choke down. Once you throttle it, it dies out. Any help please

[Wheelman-111]

Greetings:

Could be a carb problem, but how did the symptoms start?
This requires more teardown and inspection than a Forum post can provide.

[spartan-spree]

Ok ill do a carb cleaning and inspection in a few days and come back with more information. what would i be looking for in the carb and it has been going on for awhile. ive been trying to tune the thing but the carb is in the worst spot to make adjustments while its running.

[spartan-spree]

i took apart the carb and it is a little dirty but nothing bad. i cleaned everything and all the jets are cleaned and the float is works too. ill try to put it back on and see if there is any success if not. whats the next step.

[Wheelman-111]

Greetings:

Hopefully a thorough cleaning has solved your problem. Wanting to run only on the choke suggests that the mixture without choke is too Lean - not enough fuel for the air the engine inhales. One way that can happen is if the carb itself isn't allowing enough fuel through its jets to produce a combustible mixture. Hopefully you've addressed that possiblility by cleaning.

But another way the mixture goes Lean is if the engine has found a way to pull in extra AIR somewhere. This can happen as gaskets and rubber seals dry out and fail. Common places for that to happen on Hondas include the airbox/carb connections - Super-sensitive Sprees, especially. If you even remove the air filter or even a crack in the rubber box-to-carb connection can wreak all manner of havoc on those models, and perhaps the same applies to the similar Yamaha Razz? Other places to look for leaks include the reed block gaskets, oil pump o-ring, base-head-exhaust gaskets and more rarely crank-end seals.

If the engine will idle, you can fumigate each suspicious junction with an UNlit propane torch. Some prescribe carb cleaner or any sprayable combustible. Be careful not to set your scooter/yourself on Fire as you try this. If the idle speed changes AT ALL when you introduce the propane/spray cleaner, it's sucking in air/gas where it should be airtight and you've found an issue. I caution you that left unchecked, a Lean situation causes the engine to overheat with sometimes catastrophic results to the piston/cylinder, so don't run it hard if you run it at all.