[DiscordRx]

Good morning everyone, I just recently bought a Yamaha 650 Vstar that sat for about 9 months, I took off the carbs and cleaned em, I have compression, Spark, Air, and the fuel pump seems to be running perfectly fine.

Here's my issue, I can bounce off the rev limiter in neutral, but the second I am in gear I cant go past a quarter throttle without the bike sputtering really hard then wanting to die. I am at my wits end i tested the tps module on the carb and got .75 closed and 4.30 all the way open but was told the tps could still be faulty. I am truly stumped and don't want to take it to a moto shop cause I feel its something easy and hopefully cheap.

 

[Jspree]

I can think of 2 things real quick, first when you took the carbs apart did you take a strip twist tie and clean all the little holes in the jets? if not that could be one problem .
Second air leak on the intake manifolds, these manifold are rubber, the get cracks in the rubber and they have a single o'ring as a seal and everyone replaces them dry. replace the o'rings with a small amount of sealant.
This should solve the problem, if the manifolds are cracked replace them, they are real expensive.

 

[dmil123]

First welcome to the forum from Rochester NY. Please use the new member thread to introduce yourself...age, location, newbie or old pro, bike yr and mileage, bike upgrades, etc. To add to Jspree's info, the carbs have multiple jets that come into play at various throttle openings, so make sure they are all clean...

 

[DiscordRx]

I can think of 2 things real quick, first when you took the carbs apart did you take a strip twist tie and clean all the little holes in the jets? if not that could be one problem .
Second air leak on the intake manifolds, these manifold are rubber, the get cracks in the rubber and they have a single o'ring as a seal and everyone replaces them dry. replace the o'rings with a small amount of sealant.
This should solve the problem, if the manifolds are cracked replace them, they are real expensive. View attachment 101210

Thank you so much, is there a way Ican test to see if the intake manifold is bad? they dont looked cracked from the outside from what I see

 

[Jspree]

If you have some carb cleaner, spray around the base of the intake with it running , if it changes sound it is leaking. You will be able to hear the difference if it is leaking.

 

[DiscordRx]

First welcome to the forum from Rochester NY. Please use the new member thread to introduce yourself...age, location, newbie or old pro, bike yr and mileage, bike upgrades, etc. To add to Jspree's info, the carbs have multiple jets that come into play at various throttle openings, so make sure they are all clean...
View attachment 101216

Hi! yes i was able to clean all of the holes on the individual jets but I think I may have someone else recelan the carbs just in case i didnt do it properly, sort of a double checking of my work.

 

[DiscordRx]

If you have some carb cleaner, spray around the base of the intake with it running , if it changes sound it is leaking. You will be able to hear the difference if it is leaking.

Ill do it when I get off duty, thank you so much ill keep you updated

 

[Jspree]

You military? I did 10 years in Uncle Sam's canoe club ( USN)

 

[DiscordRx]

You military? I did 10 years in Uncle Sam's canoe club ( USN)

No sir, thank you for your service, I am a Security Sergeant/Motor Officer here in Arizona

 

[Jspree]

Atleast you are not freezing , if you have any more problems, just yell. we will figure it out and get you on the road

 

[DiscordRx]

Atleast you are not freezing , if you have any more problems, just yell. we will figure it out and get you on the road

Just did the test, no change in idle speed , I have her running right now, same issue, I can rev her out in neutral but she won’t go past quarter throttle underload

 

[DiscordRx]

Atleast you are not freezing , if you have any more problems, just yell. we will figure it out and get you on the road

second update, I took it for a slow test drive around the block, now it doesnt want to move in first gear at all UNLESS the pull the choke out which causes the bike to rev super high but makes it (barely) ride able aroudn the block, if i pull the clutch in the rpms skyrocket

 

[Jspree]

that sure sounds like too much air and not enough fuel. If it is not sucking air from the intake then it has to be starving from the carb . You have to have something blocking fuel in the carb.

 

[Jspree]

Do you have stock airbox and exhaust?

 

[dmil123]

just spitballing other ideas here.... any chance one of your brakes is dragging and pulling the engine down when in gear? Does the bike roll easily back and forth in neutral? Les and Jspree will be more helpful if its a carb issue.

 

[DiscordRx]

just spitballing other ideas here.... any chance one of your brakes is dragging and pulling the engine down when in gear? Does the bike roll easily back and forth in neutral? Les and Jspree will be more helpful if its a carb issue.

yessir it moves freely

 

[DiscordRx]

Do you have stock airbox and exhaust?

Aftermarket exhaust which has been on the bike its whole life with no issues, stock airbox with k&n airfilter, I am assuming I should have the carb professionally cleaned

 

[lesblank]

Can you pull the plugs and post a picture. We can tell if you are running lean or rich. I'm thinking you are running lean, check fuel flow after fuel filter, might be clogged. Other issue might be carb floats might be set to low making bike starved for fuel anything past idle.

 

[DiscordRx]

Can you pull the plugs and post a picture. We can tell if you are running lean or rich. I'm thinking you are running lean, check fuel flow after fuel filter, might be clogged. Other issue might be carb floats might be set to low making bike starved for fuel anything past idle.

let me go pull a plug stay tuned

 

[DiscordRx]

Can you pull the plugs and post a picture. We can tell if you are running lean or rich. I'm thinking you are running lean, check fuel flow after fuel filter, might be clogged. Other issue might be carb floats might be set to low making bike starved for fuel anything past idle.

so having a weird issue, none of my spark plug sockets are fitting over the plug