Bad mileage/ strong exhaust

VMAX  Forum

Help Support VMAX Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

jmailley

Well-Known Member
Joined
Aug 10, 2011
Messages
71
Reaction score
3
Location
Jacksonville, OR
I see you guys are getting 100+ miles per tankful of gas. My low light goes on @ 79-82 miles. I haven't pushed it to see how far I can go after that but it seems not far. I've leaned it out to just over 1 turn out (extremely lean by what I read here) and still I am getting a very strong exhaust and low mileage. I changed the valve cover gaskets and cleaned out the carbs and intakes after they had been soaked with oil. Oil had also gotten into the intakes and I cleaned them as best I could then ran crab and throttle cleaner through 4 tanks of gas. After running the cleaner I pulled the carbs/intakes again and there is still some oil in the intakes but not much. Plugs don't look too light and seem to be firing fine. Thoughts? Fixes?
 
How do you ride it? Granny-riding will get you 100+ miles to a tank. Lots of Vboost time will get you 70-80 miles per tank..

When you say strong exhaust, do you mean it smells of gas?
 
I ride pretty rough. Not insane. No redline, but up to 9,000 rpm. I set my SASY to turn boost on at 3,000 or 4,500 depending on how I feel. I don't like keeping it on all the time because the whole fun of the vboost is getting to feel it kick in.

I get 110-120 mpg before reserve, but never less than 100. You may have a small leak.
 
It would help to know what setup you are running, ie jet kit, exhaust, etc. If you are running a Stage 7 kit with aftermarket exhaust and the Vboost eliminators in you will see a drop in mileage compared to stock. Details plz.
 
I ran into a similar problem. Mine smells heavily of rich exhaust at idle and am lucky to get 29mpg. Yesterday I finally drilled out my brass plugs and found almost all the screws less than 1.5 turn out, one being 7/8 turn out. This is far from the 2.5 turns out I've read about and even experienced on my last Vmax. And it looks like I'll be leaning them out additional.
Mine is a 2002 with a K&N being the only modification.
 
I ran into a similar problem. Mine smells heavily of rich exhaust at idle and am lucky to get 29mpg. Yesterday I finally drilled out my brass plugs and found almost all the screws less than 1.5 turn out, one being 7/8 turn out. This is far from the 2.5 turns out I've read about and even experienced on my last Vmax. And it looks like I'll be leaning them out additional.
Mine is a 2002 with a K&N being the only modification.

Turning the screws out adds fuel.
you might want to check the floats. On my 06 I found them to be rich from the factory
 
Well i am no expert by any means. But my 86 was fouling plugs bad an also smelled of gas very strong. Went through alot of gas just idleing an running it in the drive way. Have an appp next week to have the carbs looked at. I did find that all four plug wires were in awfull condition. Front left had no wire in it at all! I have changed these an it runs like a totally diff bike. An that overpowering gas smell is gone an no foulded plugs yet. So i.d.k. So when i get these carbs looked at i hoping i'll be 100% Good luck!
 
Running all stock with no mods that I can see or know of. I'm doing some electrical work this weekend to the charging/ rr system so I'll take a look at the plug wires. Thanks for the help.
 
I have a tboost switch that I rarely ever put in the 3000 mode. I do get it up into vboost a bit here and there when getting on the highway or long road but not enough to get 80 miles per tank consistently. I think this is electrical. That's where I'm gonna start. Does MSG make an ignition box for this bike or are there any better options other than stock?
 
I have a tboost switch that I rarely ever put in the 3000 mode. I do get it up into vboost a bit here and there when getting on the highway or long road but not enough to get 80 miles per tank consistently. I think this is electrical. That's where I'm gonna start. Does MSG make an ignition box for this bike or are there any better options other than stock?

MSD does not.
Dyna 3000
or
http://www.vmaxforum.net/showthread.php?t=19130
 
I get 105-110 miles before the light comes on riding hard, and vboost starting to work at 3k. And, I know I'm on the rich side still.
Steve-0
 
I went 119 miles, 2 up on my 94 last weekend before the light came on. Actual 122 before it started caughing. Sean said this bike is just a touch lean to make great HP based on my dyno sheet but is right on for good mileage... My 89 is a Gas Guzzler for some reason. It also runs like a Bat Out Of Hell...
 
Back
Top