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Discussion Starter #1
i bought a cheap, non-running VMax for $650.00. i cleaned the carbs and got it running but it's running lean. it will idle but when i blip the throttle it sucks air and wants to die. so i'm thinking of raising the float level and or putting bigger main jets in it. any suggestions would be greatly appreciated.
63989
 

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Welcome to a great forum!

You probably have a vacuum leak and DON"T mess with the floats or main jets, these will just compound the problem.

I had a new 1989 V-Max and they ruled!!!

Sam :)
 

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i bought a cheap, non-running VMax for $650.00
Dang! I never come across deals like that. Even though I generally won't touch a bike that old I might make an exception for a Mad Max.
You probably have a vacuum leak and DON"T mess with the floats or main jets, these will just compound the problem.
^ Words of wisdom ^
There is a "jet block" inside the carburetors that has a gasket and an 'O' ring under it. Those need to be in place and in good shape. I'd check to be sure those are okay... Just a stab in the dark guess.

S F
 
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Discussion Starter #4
yeah, i cleaned the carbs twice so it's not a problem with the block. having said this i might go through them again to make sure.

i looked for a vacuum leak but it'd have to be a big leak for it to bog so badly.
 

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Are you sure it's getting enough fuel to the carburetors?
If I remember correctly it's easy to get to the fuel bowl drain screws on that bike. After it bogs you could turn off the ignition switch (fuel pump with) then drain the fuel bowls to see how much fuel comes out.

S F
 

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That is a great looking bike and a handfull when you get it running right.
 

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Discussion Starter #8
That is a great looking bike and a handfull when you get it running right.
yes, i previously thought it was goofly looking but now it's retro, goofy cool. i'll post a link to the bike idling below. i have to go through the carbs again because it's sucking too much air and dying when i blip the throttle. there must be some passages still gooped-up. but getting it this far was huge and i know that the motor is good.
Vmax Idling
 

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I always thought it was a very good looking machine. I seem to recall it was considered a killer in it’s time. Is my memory playing tricks on me and it was another with a similar name?
 

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Discussion Starter #10
I always thought it was a very good looking machine. I seem to recall it was considered a killer in it’s time. Is my memory playing tricks on me and it was another with a similar name?
no, when it came out it in 85 was the baddest bike around. what i don't like are the fake air intakes. but now it's considered retro cool. my bike still has the original 55mph speedo where 55 is highlighted in red. lol...
 

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Yamaha's V-Max was the original Boulevard Cruiser. A real bad ass from stoplight to stoplight.
A unique and bold machine in it's day... I always called it Mad Max.

S F
 

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no, when it came out it in 85 was the baddest bike around. what i don't like are the fake air intakes. but now it's considered retro cool. my bike still has the original 55mph speedo where 55 is highlighted in red. lol...
Glad my pea brain hasn't gone completely south on me. I wanted one but was not sure I could handle it. Instead I got a tractor. An 85 Electra Glide. Probably best I did. I would probably been one of the fatalities.
 

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no, when it came out it in 85 was the baddest bike around. what i don't like are the fake air intakes. but now it's considered retro cool. my bike still has the original 55mph speedo where 55 is highlighted in red. lol...

Those aren't fake, there is a flap that should open up around 5-6k, it gives you a ram air effect. I have an 07 RSTD that has the same engine, detuned and smaller carbs. It still has some grunt.
 

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Discussion Starter #14
Those aren't fake, there is a flap that should open up around 5-6k, it gives you a ram air effect. I have an 07 RSTD that has the same engine, detuned and smaller carbs. It still has some grunt.
no, they're fake. on later Vmax they made them functional but i can't tell you when they did that. i just pulled the carbs again. fake fake fake....
 

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I believe V-Max went fuel injected in 2009. I've never been inside, or even seen, an F I Max that I remember.
Possibly that's when the fake air intakes were no longer fake?
According to a quick online search there is a servo motor that changes the length of the air horns (velocity stacks) inside the air box to more ideal lengths as it relates to engine RPM. Longer for lower RPM, shorter for higher RPM.
It has to do with 'catching' the better sonic waves (caused by valves slamming shut) inside the intake tract as engine speed changes.
I've seen the system in R-6's and I understand the R-1 has the same as well as some other brands too. I've never understood why manufacturers didn't do variable intake tract lengths many years before they did because the information has been out there for well over 30 years that I know of.

S F
 

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Discussion Starter #17
I finally got it starting, idling and revving so i put it back together and took it for a test spin. no plates but what the hell.. this bike is so fast that it went crazy without a full throttle. WOW. it's much faster than my Buell's . it actually stops and handles well too. everyone said that they were just a straight line machine but that's not true. it's a fricking BEAST. i'm going to install drag-bars, LED turn signals and paint it. soon, i'll upload a video of this monster riding down the road.
 
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