1989 Yamaha pro 50 bogging down

[mattkline205]

I have a 1989 Yamaha pro 50 that is bogging down under a load. In neutral it will free rev no problem but as soon as it put it in gear and under a load and give it throttle it misses and bogs down. It’s a 3 cyl compression is 120-top cyl, 118 middle cyl, 120- bottom cyl. It had 3 brand new coils, new rectifier, good stater, good rectifier, carbs have been cleaned and new reeds. When I replaced the stater it ran good for one morning then started running bad again. I’ve attached a video of how it runs under a load

 

[99yam40]

go thru the carbs again, something has plugged up a jet

 

[mattkline205]

I’ll check that tomorrow.

 

[mattkline205]

go thru the carbs again, something has plugged up a jet

It had brand new 60 carbs on it and that didn’t change anything

 

[99yam40]

It had brand new 60 carbs on it and that didn’t change anything

60 carbs on a 50 would not work well

 

[racerone]

Most motors rev up in neutral.---Even running on 2 of 3 cylinders.-----Not a good test of anything.----Have carburetors been properly synchronized with vacuum gauges ?

 

[mattkline205]

Most motors rev up in neutral.---Even running on 2 of 3 cylinders.-----Not a good test of anything.----Have carburetors been properly synchronized with vacuum gauges ?

They have not

 

[mattkline205]

I took it out tonight to see how it would do off the trailer. If I eased on the throttle it would start to plain out then start missing and the rpms would fall off

 

[99yam40]

I helped my BIL with a problem similar to this on his 50
All I found was debris in #3 main jet
cleaned that out and it ran fine

 

[mattkline205]

I helped my BIL with a problem similar to this on his 50
All I found was debris in #3 main jet
cleaned that out and it ran fine

ill pull the carbs apart today and see if I cant find anything. wot I can look inside the throat of the carb and it looks to be a pretty good amount of fuel coming through the jets. I also took a spray bottle with some mix fuel and while in gear and WOT I sprayed some into the mouth of the carbs to see if it would stop the skipping and no power and that did not help which makes me think that it is a timing issue not a fuel issue. thanks for the reply ill take any advice given.