New Owner... Carb Issues I Think....

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Sounds like fuel tank has some bad shit in it. I would inspect that carefully.
 
Mark have you ever had to remove the tank? What type of pickup is in there? It is strange because wot there seems to be no issues with starvation......i am intrigued
 
You have to remove rear wheel and let swing arm hang down. I have some pics of the procedure that I can email you. Let me know. I just find it suspicious that the problem gets worse as fuel level gets lower.
 
I would suggest that before removing the tank, to drain it first to see what comes out - there is a drain bolt at the bottom of the tank. Then take a flashlight and look inside to see if tank has rust, etc,,,

Mike
 
I think i would like to try and drain the tank first. I have not inspected the tank very much and i suspect rust. Is the fuel pickup in the tank similar to a gravity type with a screen? I am just trying to figure out why it is getting worse with a lower fuel level... Is there a drain hose on the bottom of the tank? If not i will pick up a piece of rubber hose on my way home. HaS anyone done this procedure in the past? Can i give seafoam to my sick cat to cure incontinence?

I am not too keen on spilling gas all over the garage
 
THE SEA FOAM IS A GOD SEN'T ! TRUST ME ! IT MAY RUN ERATTIC HEAR & THERE WHILE IT WORKS ITS MAGIC ! AFTER YOUR SATISFIED THAT ITS RUNNING PRETTY GOOD & YOUR DONE WITH THE HEAVY DOSES OF SEA FOAM & ARE DOWN TO ONLY 1 OR 2 OZ. PER TANK , THROW ANOTHER NEW SET OF SPARKPLUGS IN IT ! KEEP US POSTED ! :punk:
 
I removed my tank to apply the KBS Tank Sealer. It is not difficult if you follow the instructions, just a little time consuming. I have attached a copy of the instructions. Might be a good idea to make this a "sticky".
 

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I removed my tank to apply the KBS Tank Sealer. It is not difficult if you follow the instructions, just a little time consuming. I have attached a copy of the instructions. Might be a good idea to make this a "sticky".

Done, sticky thread created. Thanks for the input Don!
 
Thanks everyone can i get to the drain plug without having to go through all these steps? I would like to try and drain the gas (and rust) out. Is the plug accessible? Sorry the bike is parked far away from me at work here......
 
If you have stock mufflers those will need to come off first.
 
Yes they are stock
if i spend one more night in the garage working on my new baby and ignoring "the one who must be obeyed" i will have more than just rust in the gas tank..........where did all the sugar go sweetheart?
 
Ok i am about to give up here and take it to a "pr0"
anyone know a good yamaha vmax mechanic in the montreal area?

The symptoms:
Now hesitates at all speeds (more so at roll on) regardless of fuel level worse now than ever,
backfires through the carbs and exhaust, stalls when coming to a stop and pulling in the clutch (that is a dangerous one especially at intersections),
misfires/hesitates when going over bumps (at first i thought it was an over sensitive throttle but it is not, something must be loose)
the ride in to work is scary enough in quebec on a healthy bike (picture a roundabout in france where every newly licensed driver is road raging while talking on the cell phone with the tax auditor)

what i have done so far:
Complete carb teardown clean and sync, changed the original fuel filter twice to be sure (14.00$ from yam thanks guys, would you like vaseline with that?)
multiple pea and shotgun's,
seafoamed until i was foaming at the mouth (president of seafoam just completed marble work on the urinel in bathroom 18 in wing 8 of the estate thanks to my max it is nice though)
cleaned and checked every connector i could find (all were clean no green),
changed plugs & wires (plugs twice)
a/f screw is set at 3 out

my patience with this bike is getting as thin as keira knightley with the trots in new delhi
 
After reading this thread I am beginning to think you are barking up the wrong tree concerning the carbs. My bet is that this is a fuel delivery issue. Start checking the fuel pump out as the culprit. It is a simple diaphram pump and if your tank has schmutz it can get "jammed" for lack of a better term and not pump properly. If your tank has rust you need to clean the system back to front.
 
i checked the pump for flow and it seemed to be ok, have not really gone back to it though have not taken it off is there something i can do once it is off? i will look at that tonight thanks for the tip
 
If you pull it off I would open it up and check the diaphram for pin holes, check to make sure that there is no gunk built up in it, and check for freedom of movement.
 
thanks again.....at this point i am going to try anything

this really has me stumped.....i have never had so many problems getting a motorcycle tuned correctly but the previous owner did not store correctly and i am paying for it now...... 4oz of stabilizer and i would be able to ride right now grrrrr
 
Tiverton Ontario beautiful around there.....love to have a cottage up in that area but need to mug Dick Cheney to pay for it

thanks for the offer how much to tow it there ??? he he

has anyone ever bought a carb rebuild kit from yamaha? or is it cheaper to buy the parts seperately that Mark Milne has posted as a sticky?
 
thanks again.....at this point i am going to try anything

this really has me stumped.....i have never had so many problems getting a motorcycle tuned correctly but the previous owner did not store correctly and i am paying for it now...... 4oz of stabilizer and i would be able to ride right now grrrrr

MM, do you have a auxillary gas tank? I would take the fuel line from fuel filter off the tank and attempt to run it from that.

Turbostang, you out there? He's a carb guru.
 
Mark I drained the gas tank last night, it was clean. 2nd flashlight inspection looked good. I replaced the fuel filter again for good measure. the bike ran worse than ever on the way to work today hesitates at all rpm's now ???? backfires really bad too made me want to weep after all the scraped knuckles and choice language
my next step is to tear open the fuel pump although I do not relish the idea workspace on this bike is as tight as my leotard after the chinese buffet
 
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