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Ridgeway, am I reading this right? You managed a 136 mile loop on 4 gallons? Any idea how much difference your CVT mods made? When I get around to my own CVT mods, MPG will be an important factor for me.
My 660 holds 5 gallons, @4 gallons on the main pet cock setting with a reserve for the last gallon. I was coasting down the mountain back to the truck on Cork Screw and within 200 yards of the truck had to switch to the reserve part of the tank to keep the engine idling while the bike was pointed downhill.
The c.v.t. mods and taller tire combination make all the difference, remember I do run a stock engine with a 2" exhaust tip and the air box lid is full of holes, and I did that loop with 3 member witnesses :)

You're one of the few catching on to what I'm doing, as it turns out what I learn for the 660 actually works for the 550's and 700's toooooo.
By accident I stumbled onto the best tire size for the Grizzly engine, c.v.t. and transmission combination, then I offer it up in my signature and answer questions. I don't get involved in worthless tire model arguments; I don't care what tire tread you like or what tracks you like to look at.
What is important for best performance is the required number of axle rotations per actual mile of distance traveled. Most here don't realize the stock Griz odo reads high, indicating higher speed than actually traveled, thus greater distance traveled than actually ridden.
Because most don't understand that fact they don't think about a trail sign saying its 'x-number of miles to...' the end so they can run out of gas.
In the city when you're close to a town its may not be important to know the true range of your machine, but here a mistake can easily cause death.
I learned this one day when our member Pot Pie (my buddy) bought a used stock 660 just like mine because he was impressed with how mine worked. We went riding one day and after a short morning ride with another member here rio, all starting with full tanks, the others all took more gas to top off after the ride....hum.

I don't use my G.P.S. receiver when riding but rio does, so I never thought about a bike not covering a true mile of distance for every mile of travel indicated. After getting back to the garage all 3 bikes had different roll-out measurements from 3 different true tire sizes with mine having the greatest distance of travel per axle rotation between the three, hum......

It then turned out that Pot Pie's stock 660 tires had a 23.5" roll-out, rios tires had a 25" true roll-out and my tires had a 26.5" true roll-out with my tires causing a odo speed read-out that matched rio's g.p.s. receiver.
At 20 m.p.h. on the g.p.s. my 660 indicated 20, while rio's indicated 23 m.p.h. and Pot Pie's 660 indicated 26 m.p.h. at 20 m.p.h. true speed, hum.....

I have installed c.v.t. mods that magnify the torque produced which in reality under most riding conditions require the engine to produce less power, requiring much less throttle thus requiring less gas.

For those that remember my postings of a day ride with Hammer a few years ago, we each rode 455 miles across the local mountains here and did the total ride distance in 17 hours, leaving camp at 5:30 a.m. to return to camp at 10:30 p.m. That's 910 miles total and we carried all gas required for the day from camp not needing to stop in towns closed to a.t.v.'s during the day. At 20 m.p.g. that would mean we needed 45.5 gallons stored on the a.t.v.'s.
We left camp with 45 gallons on board between the 2 machines, and had gas to spare because my 660 was getting much more than 20 m.p.g.

When you get around to c.v.t. mods I suggest thinking about your bike performance is three different area of need.
1) Short term low end performance coming out of the hole, using a high ratio and 3 gram heavier weights.
2) Mid range cruising requirements for comfort and safety requiring the cut cam-plate against weights at 20 m.p.h. in my conditions.
3) High speed distance traveling at the lowest engine r.p.m. for economy, requiring you determine the amount of angle you need in the new cam-plate ramps. Do you need 2 mm's, 3 mm's or 4 mm's of bend before welding the cuts closed?

I the case of the 455 day ride we averaged 26.7 m.p.h. for the entire day. We did stop for gas from the cans, along with beer from the cans too (we did stop at the edge of Delta, at the liquor store for more beer and a bag of ice, that store didn't sell gas). We could light a smoke while traveling :)
Now if you go back and understand the videos I linked from that day you'll see us traveling at speeds under 20 m.p.h. in rough conditions meaning we did a lot of higher speed traveling when the terrain allowed. So you know I took a fly rod and Hammer got his first trout on a fly rod, it was a stop just long enough for one fish off the bucket list then we hauled ass again to keep the average speed up.

Many members are spoiled by plug and play toys, the Yamaha c.v.t./tire combination isn't that way. You get out of it what you have time to put in, have fun.
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