ace1954 wrote:
My local bike shop didn't have any tires in stock for the sizes I wanted. He did have E3's that he put on the T...130/70-18 front and 180/60-16 on the back. I like them so far. My questions are: 1) what is my total speedo error with these tires (I know there is the usual speedometer error and a correction factor for the shorter tire), 2) if my speedometer says I 've gone 100 miles how many miles have I actually ridden, and 3) is my engine now running faster or slower at 65 mph then before the change. My old tires, which had 12k on them, were the factory size Dunlops.
1. Whatever your speedometer error was with the stock tire (130/80-18) it is now reading 3.9% faster than it should with the Elite 3 (130/70-18). Thus, if you have no speedometer error before, now when the speedometer indicates 65 mph the bike is really only doing 62.5 mph due to the smaller front tire.

2. If your odometer was correct before (please note that the odometer and speedometer errors are different) when your odometer indicates 104 miles, you have only really travelled 100 miles.

3. With the shorter rear tire (180/60-16 vs 170/70-16) the engine will run 3.4% faster at the same bike speed. Thus, if your engine was running 3000 rpm at 60 mph, it will now run 3106 rpm at 60 mph.

FYI, 130/70-18 is a Gold Wing size tire as is the 180/60-16. Valkyrie sizes are 150/80-17 & 180/70-16.


Fred