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Just wondering what kind of mileage range I will get with my newly purchased 83 vmax 540.....that gas tank is pretty small, plus my sled has 44mm carbs (some porting too, otherwise stock...I think!) Needless to say I am a bit concerned, and already trying to figure out how/where I can mount a remote 3-4 gallon spare tank. I saw Chuck's idea in an earlier post, and I would like to try something like that but maybe bigger, if possible.

So, about how far will I probably be able to go with the stock setup?

Tom

Tom If you read the Dyno Tech articles they show there would be no gain in using bigger carbs than the 38's. It's not like the 540 needs any help on the top end and actually bigger carbs would just be dumping unnecessary fuel ? Yes, I never understood what Yamaha was thinking using such small tanks on so, many of their sleds ? Worst case, If you're really hard on the throttle or you're sled is out of tune 6.3gal x 10 mpg. = 63 miles and if you have my sled 6.3 x 16 mpg. = 100.8 miles.

Unfortunately, the 44's are what I got the sled with, so I need to live with them. The good news is that it runs great!

The thing is, this sled was originally owned by a guy who did nothing but drag racing, and I am just trying to figure out what has been "modded" (I bought it from the second owner, who knew nothing about it).

If the guy put on 44' carbs you can bet! Heads are cut and it's polished and ported

Undertaker#13 wrote: If the guy put on 44' carbs you can bet! Heads are cut and it's polished and ported

If this is true you better use good gas ( high octane).
Just because someone mods their sled and talks a good game does not mean they know what they are doing.
There is a "science " to "porting" and "shaved head" mods. (cc, squash band, etc.)
Like they say "a little knowledge is dangerous"
I would be careful with that sled, If it runs good and doesn't break I would leave it alone.
When you talk about "stock set-up" and going back to stock. I think it is too late for that.
You might be asking for more trouble than you bargained for.

Hi jipcee, yes I would use High octane fuel in your Vmax. Also it's easy to tell if it is polished take a pipe off and feel inside if it's smooth your polished and rough feeling is Stock! I've been to the tear down shack a few times and was they ever shocked when they found my Vmax was Stock I run Regular gas in my Vmax after reading a tech article on Fuel, I I have alway's run 105 VP fuel, but after testing the 93 fuel last winter, I won't waste $$$$ in racing fuel! Now the next step for you. It's tough to trail ride a mod sled that is set up for racing The good side to this the Vmax must haul A$$!! I run high 90's with a stock Vmax in 1000ft