I covered half of the y cover and it runs !

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gslate

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Dear Fellow Rider,

My name is Gee. Ive recently joined to learn more about my new toy from fellow members.

I got the bike a month ago, and it would bog down after 5000 or so rpm. Up tp about 4000 it had the power to burn rubber....

Things Ive done in order.

1. Checked battery off 13.05 running 13.5...reving it drops to 12.75 and bounces back up. Got a new battery.
2. Cleaned the spark plugs. Okay. Replaced them.
3. Checked the resistance across the coils. Fine. Checked the spark on the plug while running. Nice and bright.
4. Cleaned Pea Shooter shotgun style....still the same....
5. Drank 5 beers.....still the same.....
6. Checked fuel pump....cleaned it and runs fine with a nice amount of carb friendly pressure.
7. Checked the boots with propane for air leaks. Not a single hole anywhere.
8. Lastly, at the ends of my wit. I remove the whole carb and clean every nook and cranny, orifice. Set the bowls back to the same height..... yet still the same.


And then like any man that is frustrated I remove the y pipe cover and STUCK MY FINGERS in the hole. With an orgasmic eruption the Max revs like a champ ! Um what just happened.

When I covered half of the y plate with DUCK tape it restricted the air flow on one side. But I do not understand why it would run better?

I am at the disposal of the experts here. I do not claim to be an expert of any sort. Please, offer your kind words of wisdom or make fun of me. Both are welcomed. If you need more clarification please ask. Safe ride brothers !:biglaugh:
 
It runs better because you have altered the air/ fuel ratio nearer to what it needs.
I would check what main jets are fitted.
 
Traumahawk will have this one. I believe he's got some notes about this process somewhere. Go back and repeat number 5 until he shows up.
 
Covering one side of the Y does not restrict the flow to one side, it just restricts the flow to all 4 carbs making the bike run richer on all 4 carbs. Like Steve mentioned you altered the A/F mixture to the rich side. Stock main jets are 152.5 and usually the stock jets tend to make the max run a bit on the rich side with stock exhaust. Do you have a stock exhaust system or some kind of slip on exhaust?
 
First thanks for the replies! As soon as a read them I ran out of the pad to the shed to take a peak.

DaveSax36 - I will repeat number 5 as suggested.

Maxmidnight - I apologies if I am incorrect. I looked at a diagram that I used for the peashooter I did a while back. PAJ2 or the one on the side is 170. PAJ1 the one on top of the carb when I remove the box says 90? Is this the same as the main jet? Noted on the air-fuel mixture. Thanks that makes sense.

alorio1 - Slip on supertrapps with 7 discs attached. I noticed that if I restricted the air by placing my hand inside the intake filter under the y plate it worked like a champ. So I placed it all back together and slapped duck tape on the one side knowing it would restrict the flow to all four carbs. Thanks for the stock numbers it give me something to go on.

On a small side note. This is my first time joining any forum. And this post likewise was my first. Big thanks to you all. I am a believer in joining forums now. I can tell that the brothers and sisters that are a part of this community are good people.

At the end of the day is there any way to fix this or did some monkey think throwing larger jets would make this bike faster? Go back to stock jets?
 
Traumahawk will have this one. I believe he's got some notes about this process somewhere. Go back and repeat number 5 until he shows up.

Thanks for the vote of confidence Dave.

So if you have to cover up parts of the airbox, that means that your getting too much air. I am curious as to what the main jets are....but I'm also curious if someone messed with PAJ1 or #2.

Here's how to check the main jets.

http://www.vmaxforum.net/showthread.php?t=3570

PAJ#1 is in thje very top of the carb as your looking down into it. It should say 90 on it.

PAJ#2 should say 170 on it.

Stock main jets should be 152.5's.

Here are some pics to help get you situated. In the last pic PAJ#2 is arrow 3, and arrow #1 points to an O ring that you dont want to lose
 

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LOL...well you answered my question about PAJ's while I was posting...lol
 
If you plan to change/verify main jets, you will have to remove them by disconnecting from intake manifolds. The main jets are only accessible from the bottom of the carbs by removing the brass plugs from bottom of fuel bowls shown in pic I have attached. There are still a couple of things to do before taking the carb out to maybe make it run better. You can back the A/F screws out a to 3-4 turns out, shim the needles up and run some Seafoam fuel treatment thru a couple tanks of fuel to clean gummed up jets.
 

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Waiting on second appointment. Still feeling pretty loopy if I move around. Holding still is fine. Got hit in the head with a falling whiteboard.
 
So now I'm also wondering if the bike is getting too much air because the airbox isnt properly seated on the carbs.

Ive also seen airbox's in the past that would have extra holes drilled in them.
 
Traumahawk

Mine has the same symptoms.
It will not run "with power" unless I cover 1 /2 of each air intake on the Y. (same thing as covering one full intake).

I cannot begin to list the things I have done, trying to resolve this issue.

If you can name it, I've have done it.

If you can think of something in your past experiences that might shed some light on this, that would be AWESOME!!
 
What are yalls float levels like? If the floats are off it will make too lean or too rich? So if its lean....theoretically you would have to decrease the amount of air as well.
 
Said it before and will say it again - rather than just trying different things and hope they will make a difference a much cheaper way in the long run, unless to have toooo much time on your hands, is to have a baseline dyno run undertaken.
That way you will know exactly what the air/ fuel ratio is and you will have a basis with which to start making changes.

If money is so tight then at the very least do a plug chop.
 
I would have skipped the peashooter and gone straight for the shotgun, follow intructions for this cleaning method and see how it turns out.....................................Tom.
 
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