tires/gas mileage

[baffled]

will a rear tire  .75 inch smaller than stock change rpm at any given speed enough to affect gas mileage?  thank you

[Paxton]

Baffled;
I went from the OEM tire to the largest car tire that the Valkyrie would accept (205/65/16).

My RPM went down from 3500 @ 75 to 3250 @ 75. Whereas I like it better, I have not noticed any MPG changes. 30 MPG before and after... ???

If I understand your scenario correctly, going with a smaller tire would do the inverse... I believe that you'd be running 3750 RPM @ 75 MPH.

Do NOT take my word for it though. Am sure there is somebody out there that can share their actual experience w/the set-up that you are contemplating.

Ride safe.

[ricoman]

Paxton, Paxton, Paxton,
you should be getting at least 42mpg (certainly not 30ish like most, me included).
haven't you followed all the mileage posts? You should be riding two up at 75+ to get the 42.
Finally, an honest mileage claim.
Thanks

[fantsybikr]

yep, I wish I had a 42 mpg valk too! I was actuallly in the 35-36 mpg ballpark until I had it rejetted for the glasspacks..now Im 30-31...I would like to ride one of those 42 mpg valks for sure..glad someone got the good ones!

[Daniel Meyer]

I get 30 with my riding habits. No change from stock, to smaller car tire, to larger car tire.

It's all in the wrist.

[PhredValk]

I think that it takes so much fuel to produce enough power to push so much air over a distance (ie, a mile) at a set velocity. Lower speeds, less wind resistance, better mileage.

If bigger tires meant better gas mileage, all vehicles would have 48" tires.
Fred.

[Sigrún]

I get 30 with my riding habits.

It's all in the wrist.

Could not have said it better myself 

If bigger tires meant better gas mileage, all vehicles would have 48" tires.
Fred.

Fred I could have sworn I saw a Hummer the other day with a set of those...... 

[Hoser]

How's this for honesty,  I seldom get as high as 40mpg, and seldom get as low as 30mpg.  180/65/16 rear tire, motorcycle type.  Hoser   

[Mildew]

When I got over 40 mpg it wasn't any fun

[Farther]

When I got over 40 mpg it wasn't any fun

Not quite as fun but when I got over 40 I was with others and having fun that way too.

[vanagon40]

Here's the deal.  If the tire was substantially larger, it would be the same as adding a 6th gear and removing 1st gear.  This would be akin to adding an "overdrive," which could increase gas mileage, especially to a rider spending a lot of time riding in 5th gear.

On the other hand, if the tire was substantially smaller, it would be the same as adding a gear lower than 1st gear and removing 5th gear.  This would be akin to riding at high speed in 4th gear, which would decrease gas mileage.

In reality, the difference in tire size of less than 3% (or 6% if baffled means the new tire is 3/4" smaller in radius as opposed to diameter) will likely not be noticeable.  I mean, how many of us ride so consistently that we would notice a 3% difference in MPG (from 33 to 32 or 34) or even a 6% difference (assuming the difference in tire size was directly proportional to mileage).

So yeah, if a person consistently rode on the interstate in 5th gear, a change in tire size might make a noticeable difference in gas mileage.  Or, if the person seldom rode in 5th gear and a change in tire size allowed the rider to shift to 5th while maintaining the RPMs he liked, the person might notice a slight increase in gas mileage, it seems unlike that the average rider would be unable to observe a difference.

[Jess Tolbirt]

another hijacked thread...

[Ricky-D]

will a rear tire  .75 inch smaller than stock change rpm at any given speed enough to affect gas mileage?  thank you

Not so you would notice!  That being you are a normally all around rider. If you were strictly an interstate rider you may notice a lesser mpg figure, but that would still be in a fractional amount of difference.

***

[bogator]

 If----a big IF----I ride below 3000 rpm's--64 mph--I get 40 mpg--BUT---above 3000--I do not know--I ride -----not thinking about it-- I ride till I go on reserve, then look for gas -----GOD BLESS & RIDE SAFE----

[CajunRider]

If----a big IF----I ride below 3000 rpm's--64 mph--I get 40 mpg--BUT---above 3000--I do not know--I ride -----not thinking about it-- I ride till I go on reserve, then look for gas -----GOD BLESS & RIDE SAFE----

Yep... 55-65 mph I can get 40... but that's the only way.