1997 Vmax 500 XT Mid range rough using lots of gas

stugny

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I have a 1997 Vmax 500XT I purchased new in 97. Only has about 2800 miles on it has has been in storage a lot over years, indoors. Last year was the first time I ever had an issue. Was dieing down after WOT. Came down to the TORS switch on the Carb. When fixing this I noticed a small exhaust leak so I replaced rings in muffler. Also installed new bereather box filter and when breather boxed was removed cleaned things up. Did not ride much after that but this year I am using a ton of gas not typical of this sled. When I say a ton like 3mpg. There are no leaks. Sled does sound different than normal at midrange 1/4-3/4 throttle. Starts first pull, idles fine but does sound a little off. WOT sounds normal and goes. Took to a shop and he said choke was sticking and cleaned carbs. I do not think he removed float needle when doing so. Not so sure how well they were cleaned. Got sled back and it still is running the same maybe a little worse. Checked compression. 115 and even in both cylinders. Any ideas???? I just pulled carbs back off to clean again anything I should be checking?? There have never been any mods to machine and would like to get it back to where it was. I did replace belt and even on jack I notice it running funny with no load. Lots of blue smoke. When I pull plugs the color is good but they are always wet even though they haven't fouled yet! I did replace plugs.
 

I have a 1997 Vmax 500XT I purchased new in 97. Only has about 2800 miles on it has has been in storage a lot over years, indoors. Last year was the first time I ever had an issue. Was dieing down after WOT. Came down to the TORS switch on the Carb. When fixing this I noticed a small exhaust leak so I replaced rings in muffler. Also installed new bereather box filter and when breather boxed was removed cleaned things up. Did not ride much after that but this year I am using a ton of gas not typical of this sled. When I say a ton like 3mpg. There are no leaks. Sled does sound different than normal at midrange 1/4-3/4 throttle. Starts first pull, idles fine but does sound a little off. WOT sounds normal and goes. Took to a shop and he said choke was sticking and cleaned carbs. I do not think he removed float needle when doing so. Not so sure how well they were cleaned. Got sled back and it still is running the same maybe a little worse. Checked compression. 115 and even in both cylinders. Any ideas???? I just pulled carbs back off to clean again anything I should be checking?? There have never been any mods to machine and would like to get it back to where it was. I did replace belt and even on jack I notice it running funny with no load. Lots of blue smoke. When I pull plugs the color is good but they are always wet even though they haven't fouled yet! I did replace plugs.

I would clean the carbs again. Make sure to either replace the pilots or get new ones. New plugs, new belt and then look over the clutches( Rollers. Weights, center bushings ) Also be sure that the throttle cable at the split is pushed back together and not apart. The inlet needs and seats could be a problem as well in the carbs. Does it start easy almost with no choke?
 
Is it backfiring at all? I would think if the needles were the issue it would be dumping enough fuel to cause backfiring.
Was the air box foam replacement factory? Don't want too dense of foam in there.
 
Is it backfiring at all? I would think if the needles were the issue it would be dumping enough fuel to cause backfiring.
Was the air box foam replacement factory? Don't want too dense of foam in there.

Factory air filter. I get no backfiring. When it is cold or has been sitting a long time I have to choke it but it generally starts after 1 or two pulls. Once it has been run it starts no choke half a pull. It only has a single cable no split. I removed the pilot screws to clean out and put them back in. I set them to 1 3/4 turns as that is what I thought I counted. I haven't installed carbs yet to retest.
 
Factory air filter. I get no backfiring. When it is cold or has been sitting a long time I have to choke it but it generally starts after 1 or two pulls. Once it has been run it starts no choke half a pull. It only has a single cable no split. I removed the pilot screws to clean out and put them back in. I set them to 1 3/4 turns as that is what I thought I counted. I haven't installed carbs yet to retest.

I would check for warn clutch parts if you think its running good.
 
I would check for warn clutch parts if you think its running good.

I dont think it is running right though. Plugs wet, not as responsive as it used to be and sounds off when just running along at 5500 -6000 rpm. Will clean carbs reall good myself and see if that helps.
 
I dont think it is running right though. Plugs wet, not as responsive as it used to be and sounds off when just running along at 5500 -6000 rpm. Will clean carbs reall good myself and see if that helps.

Make sure to pull the read cages and be sure everything looks good there as well as inside the airbox.
 
Make sure to pull the read cages and be sure everything looks good there as well as inside the airbox.

I cleaned the air box last year and when I took it off this weekend it was still clean as a whistle inside. I was wondering about the reeds? Just inspect for crack, chips and wear? Should be tight against stopper is what I was reading? There is a small brass air jet in throat of carb. When I was cleaning the carb it did feel like one was blocked, would this give it a rich condition? When I cleaned air box last year I had what appeared to be belt residue in airbox mouth of carbs. The filter was completely open on top of breather box due to a mouse. Maybe that got into these air vents? Is it possible that there is any issues with exhaust. I only say this as it seems like this all started when I fixed the tors and put new rings in the exhaust pipe. Even after running a while I can put my hand on the main pipe or silencer. Is that normal. Sorry for all the questions and appreciate the responses!!
 
I cleaned the air box last year and when I took it off this weekend it was still clean as a whistle inside. I was wondering about the reeds? Just inspect for crack, chips and wear? Should be tight against stopper is what I was reading? There is a small brass air jet in throat of carb. When I was cleaning the carb it did feel like one was blocked, would this give it a rich condition? When I cleaned air box last year I had what appeared to be belt residue in airbox mouth of carbs. The filter was completely open on top of breather box due to a mouse. Maybe that got into these air vents? Is it possible that there is any issues with exhaust. I only say this as it seems like this all started when I fixed the tors and put new rings in the exhaust pipe. Even after running a while I can put my hand on the main pipe or silencer. Is that normal. Sorry for all the questions and appreciate the responses!!

I would defiantly clean those brass air jets the best you can. The pipe should be hot. Is the pipe being blocked and that would make it run cold and rich. Check to see if there is a mouse nest in the pipe or silencer. Have you tried blowing air through it.
 
I will check the pipes again and see if I can feed some air through them. I have pipe camera maybe I can snake that in and take a look.
 
I would defiantly clean those brass air jets the best you can. The pipe should be hot. Is the pipe being blocked and that would make it run cold and rich. Check to see if there is a mouse nest in the pipe or silencer. Have you tried blowing air through it.

Question on carb cleaning. This is a flat slide carb. When cleaning when I spray cleaner into main jet with throttle closed fluid comes up around brass insert. Is that right? When i open throttle goes through main jet fine. Was wondering if that brass insert is supposed to be sealed?
 
I have a 1997 Vmax 500XT I purchased new in 97. Only has about 2800 miles on it has has been in storage a lot over years, indoors. Last year was the first time I ever had an issue. Was dieing down after WOT. Came down to the TORS switch on the Carb. When fixing this I noticed a small exhaust leak so I replaced rings in muffler. Also installed new bereather box filter and when breather boxed was removed cleaned things up. Did not ride much after that but this year I am using a ton of gas not typical of this sled. When I say a ton like 3mpg. There are no leaks. Sled does sound different than normal at midrange 1/4-3/4 throttle. Starts first pull, idles fine but does sound a little off. WOT sounds normal and goes. Took to a shop and he said choke was sticking and cleaned carbs. I do not think he removed float needle when doing so. Not so sure how well they were cleaned. Got sled back and it still is running the same maybe a little worse. Checked compression. 115 and even in both cylinders. Any ideas???? I just pulled carbs back off to clean again anything I should be checking?? There have never been any mods to machine and would like to get it back to where it was. I did replace belt and even on jack I notice it running funny with no load. Lots of blue smoke. When I pull plugs the color is good but they are always wet even though they haven't fouled yet! I did replace plugs.

Have you pulled the pulse line from the fuel pump to ensure it isn't leaking?
 
Have you pulled the pulse line from the fuel pump to ensure it isn't leaking?

I have not checked pulse line. Easy to get to right now with carb out. If bad gas will come out even when not running correct?
 
To see which way we should look. Remove the foam in the hood and go see if that makes any difference. That will unrestricted the air getting to carbs. I.E. .... a straight shot.

Are you talking about the foam under dash. I actually need to replace as it is disintegrating and getting all over the inside of the tunnel. Or are you talking the filter at the top of the breather box?
 
Have you pulled the pulse line from the fuel pump to ensure it isn't leaking?

Got the sled back together today. Cleaned carbs again. Chechecked pulse line, good, checked reeds, good. Exhaust good. Replaced filter. Gone through carbs again very closely. Did fund some small pieces in fuel jet. Reset fuel screws to spec and put new plugs in. Floats were on the low side of spec, adjusted right on the money. Once bowls filled up ut started right up. Took it for a spin and still seemed funny at low end. TORS also started hitting again when letting off abruptly and trying to get back into throttle. I temporarily bypassed didnt change much other than TORS issue went away. Just fir the heck of it I siphoned as much gas as I good get out of tank. The tiny bit left in there did look a little dirty to me. Possible due to shop seafoaming? I dumped 5 gallons of fresh gas in and it did seem like it had a little more pep? Top end seems ok 70 - 80 mph cones very easy at around 8k rpm. Any otger ideas???
 


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