New tires, bad MPG

[Tone]

Double check the dimensions of your tires compared to the stock ones. Thornbirds are some of the heaviest tires out there (even tho they are bias tires) but they look wild! Taller will definitely make mileage numbers appear lower.

[tomdietrying]

What size tires are your Thornbirds? I'm thinking about going a bit taller and wider before Moab, but if it's going to do that to my MPG I'll have to think twice about it.
Peace.
Tom

[spitfire5454]

Thanks for the info. Mine are 30x11.50R16. And as tone said, they look awsome! Here is a spec comparison to the stock tires:

Stock Thornbird

Hieght: 29.7 30.0
Width: 9.8 11.50 (probably less b/c 16x7 wheels)
Weight: 35lbs 55lbs

I purposly didnt get taller tires because i really liked the performance of the VX. This is worse than when i put 33s on my amigo. Today i will fill up and see how much i get to the tank.

Brian

[JAFO]

I been researcing for new tires and I just read an article in Consumer Reports at Lunch that said that heavier lug tires (mud/snow) have higher rolling resistance.

5 gallons / 50 miles = 10 MPG

Wow, mine gets 18-20mpg on stock R18 Duelers. Big change.

[t2p]

Spend any time on a bicycle .... especially on the road ....
.
and you will quickly see the difference tires can make ...... weight, width, tread pattern ......
.
There is a good reason 'Triathlete' .... Billy .... is riding those skinny tires !

[Tone]

Bias tires like the Thornbirds will get lower MPGs than radials as well - higher rolling resistance, more rubber on the road in this case and more weight and sligthly taller height.

Your speedo and odo are off by3% - 60 on speedo is really 62mph. Your mileage is slightly better in town than 10MPG and of course will always be lower than highway.

[JAFO]

I also forgot tire pressure. Your not running them at 5psi with bead lockers are you? :bgwg: