Air Leaks and Carbs

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I don't know of anyone else with a Vmax so no carbs to borrow :(
Pulling the cold start on doesn't make any difference .
This is why I started to think spark .
 
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Mine will idle decent but when I accelerate I feel like I'm on a 500cc bike..... Or less! And it seriously sputters and struggles around 4k rpm. I did the peashooter and shotgun twice and nothing! I had the carbs rebuilt about a year ago and have not let it sit without ridding it or at least starting it and let it run for a minute or two. It also sounds horrible! Almost like it's hitting a rev limiter when I try to accelerate. SO FRUSTRATED WITH THIS BIKE!! so I posted in this section because I was wondering if someone can post pictures of the vacuum likes to check. I know where the sync ports are but the other things to check I don't.
Thanks as always for your help!
 
Oh ok the cylinder number to one I'm aware of. I have the ones on the air box I will check them also. I took plug #2 out to take a look....
 

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Mine will idle decent but when I accelerate I feel like I'm on a 500cc bike..... Or less! And it seriously sputters and struggles around 4k rpm. I did the peashooter and shotgun twice and nothing! I had the carbs rebuilt about a year ago and have not let it sit without ridding it or at least starting it and let it run for a minute or two. It also sounds horrible! Almost like it's hitting a rev limiter when I try to accelerate. SO FRUSTRATED WITH THIS BIKE!! so I posted in this section because I was wondering if someone can post pictures of the vacuum likes to check. I know where the sync ports are but the other things to check I don't.
Thanks as always for your help!

Did they run good after the rebuild? If so, and they are currently properly sync'd, it sounds like you picked up some dirt or tank rust .
 
I took out plug #1 and it's just as black and wet, maybe even a little worse.
 
Yes it ran good for about 800-1,000 miles. I just changed the fuel filter when this started happening and I even cut it apart to see how dirty it was and pretty much nothing in it.
 
Dragmaxster rebuilt my carbs and I can't remember exactly what he said about the jets but as you can tell from the plug picture it's running rich. I have a full two bros exhaust but I changed out the exhaust can for a single supertrapp.
 
Swapping exhaust cans wont make it run rich. Its not the jets either with it running ok for 800-1000 miles.

EDIT....last year, I had a stubborn clog that I couldn't get rid of after doing 2 shotguns. I finally took out PAJ#2's, so that way FULL 100 plus lbs of air could go thru the idle circuits. Fixed it up.
 
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Dragmaxster rebuilt my carbs and I can't remember exactly what he said about the jets but as you can tell from the plug picture it's running rich. I have a full two bros exhaust but I changed out the exhaust can for a single supertrapp.

I'll email him and see.
 
I actually did do that on PAJ2! I'm going to put some new plugs in in a few, not that I think that's the problem but I know it can't hurt to do.
 
Well...... Put in new plugs and new vacuum caps on the sync ports. Took it for a ride and it was a lot better! Not perfect but waaaaay better! About 3-4 miles in BAM.... Started to ride like shit again :ummm: no acceleration at all! If I kept on the gas hard while trying to accelerate every once and a while it would take off good for a second or two and then back to the Honda rebel 250 status.
And when I pulled it out of the garage today the left front fork seal was leaking bad!
:bang head: and the water pump seals need to be replaced :damn angry:
 
This is from #4
That doesn't look too bad except maybe a tad rich on the A/F screws.
this is what mine looked like last time I checked:
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Well...... Put in new plugs and new vacuum caps on the sync ports. Took it for a ride and it was a lot better! Not perfect but waaaaay better! About 3-4 miles in BAM.... Started to ride like shit again :ummm: no acceleration at all! If I kept on the gas hard while trying to accelerate every once and a while it would take off good for a second or two and then back to the Honda rebel 250 status.
And when I pulled it out of the garage today the left front fork seal was leaking bad!
:bang head: and the water pump seals need to be replaced :damn angry:

He is in Seattle until next week.
You can try this for the fork seal or cut something similar shaped out of a plastic jug.
http://www.ebay.com/itm/MOTION-PRO-...ash=item1c6c707578:g:O5sAAOSwxp9W6vTe&vxp=mtr

#7 & #8 here are your seals---
http://www.boats.net/parts/search/Yamaha/Motorcycle/1999/V-MAX 1200 - VMX12L/WATER PUMP/parts.html
 
Awesome! Thank you! So does anyone have any ideas on the carb/fuel running like sh** problem? I was hoping that because it ran good for a few miles then the problem started happening again it might help you guys have a better idea of what it could be.
 

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