Up sizing front tire

[spark_ee]

Hi Gang. If I replace the stock 2.75x10 with a 3.00x10 on my 85 aero, how far off with the speedometer be? I figure it will show less. I replaced the rear last year and it made a big difference in the ride.

Thanks all

Spark_ee

[motormike]

Just do it...

[benji]

It'll probably make it more accurate honestly... it seems like my stock aero speedo is off by a few mph

[patthesoundguy]

My spree Speedo was more on after a 2.75 tire on the front. Mike is right just do it

[spark_ee]

Thanks all. Bigger tire sure makes a difference on the rear. I'll order one out and have it on before the riding season is over. Mine is pretty close with stock tire ( GPS check ) but didn't want to see it off 5 mph or more. That would bug me. Thanks again.

[spark_ee]

Go the new 3.00x10 on the front and big difference in the ride and handling. Speedo difference is very little. Thanks again for the advice.

* S

[Topgun]

Diameter, not the width of the tire affects the speedo..

[Wheelman-111]

Greetings:

The speedometer should read about 3% higher as the quarter-inch difference in tire thickness adds a half inch to the 15.5 inches of wheel/tire diameter you have now. Stock speedometers as delivered are at least 5% optimistic in my experience, compared to real-time GPS speed. That is deliberate, methinks, as it improves your impression of the bike's performance plus it saves you a ticket if you encounter a fussy Gendarme. Early-century 600cc sportbikes were off by as much as 12%, according to the magazine tests. The Japanese scooters I have owned always tested about 4-6% fast. Only Harley-Davidsons have nearly dead-accurate speedos, in my experience.

0.5"/15.5" = x/100. Cross-multiply. 50/15.5 = 3.22

Speedometers are going to be "off" by a percentage, not a fixed number of MPH.

[MrJumps]

Unless you take the speedo apart and put it on 35

[benji]

I just remove the speedo and fuel gauge and all those pesky things.... nothing like pushing your scooter 3 miles to the closest gas station. Up hill. Twice in one week.