99VX700
New member
All the talk about gas mileage and some stuff I've read about proper reed sealing has me paranoid. I have a 1999 Vmax 700 triple with coated Bender triple pipes, Bender porting, airbox mod, Bender roller secondary, green spring, 47-39 helix, 89Ls, w-s-w spring, 14.5 rollers, notched reed stoppers, and carbon fibre reeds. I'm near seal level and jetted 150 mains, 55 pilots, center and mag needles raised one notch. She hauls ***, but is hard on fuel. Anybody see a red flag in the specs I listed? My oil consumption seems ok...about a quart every 100 miles (sometimes more, sometimes less). Fuel economy seems pretty consistent in the 7-8mpg range. Is this all I can expect? Are maybe the c-f reeds suspect? What are opinions on aftermarket reed set-ups like V-force and Boyesen? There's no way I can imagine a scenario where I'd feel I could make 100 miles on a tank. Maybe I should slap a set of stock Yami reeds back in there. Any suggestions/opinions on this?
yamaholic22
Active member
the porting will decrease the mileage because of the added flow, the airbox mod will flow more air, so also needs more fuel. These are probably the biggest culprits. You can check the reeds if you are worried about them. Just take them out and see if they are cracked or chipped at all, and make sure the tips of the petals are resting against the reed cage, that way you know they are sealing tight. With time the reeds lose their "elastic" ability to return to the closed position, and dont quite seal to the cage. Its probably just your porting and airbox mods though, as well as the pipes. Doesn't that airbox mod make your jetting real finicky? I haven't heard any good things about that mod at sea level. Seems to only be feasible at the upper elevations
MAD MAX V-MAX
New member
I have a 2000 sxr very similar set up except porting and air box mod and im getting 10 to 12 miles per gallon i think its your porting and air box mod more air needs more fuel
yamaholic22
Active member
MAD MAX V-MAX said:
exactly
99VX700
New member
Thanks a bunch, guys. I just wanted to make sure I wasn't overlooking something to be getting that kind of fuel economy. The reeds are probably OK...they seemed to contact the cage just fine when I put them in there, and mpg hasn't gotten progressively worse. It just went south when I did everything at once...pipes, porting, re-jetting, reeds. I didn't do the airbox mod initially. Only after talking on the phone once to a Bender rep did I decide to try it. He recommended it! At least some duct tape will easily reverse that mod if it works better without the holes. I'll give that a try. I don't find jetting finicky at sea level with the mod, but I take Turk's recommendation of big pilots seriously.
GBW
New member
Read once where the porting is the big culpurt in lost fuel mileage.