Band/Gixer Conversion (week 2)

[Billy Ricks]

When I switched to the 17" front wheel I found the stock speedo was off by close to 10% on the low side.

[quexpress]

When I switched to the 17" front wheel I found the stock speedo was off by close to 10% on the low side.

Semantics ... does this mean that you are now going faster or slower than the indicated speed on the speedo?
Thanks!

[salty_monk]

It's going to be reading slow. You will be going faster than you think. Pretty obvious if you think it through.. the gauge reads by measuring revolutions of the wheel at the hub, it has no idea of the circumference.

17" has a circumference of 54" roughly & 16" a circumference of 50" without the tyre. So it should be about 10% difference (for every revolution you will be travelling an extra 5"+ than the speedo thinks you are). That's not precise because of tyre profiles etc. You need accurate diameter measurments on both wheels with the tyre mounted to be sure.

Dan

[jwhelan65]

Clocks mounted, no brake lever yet, pushed the Rizoma grips on, left the bar ends off for now, still have to locate a late model master cylinder.

[jwhelan65]

finally got to put these on, as soon as the ends are mounted they should really set the bars off.

[quexpress]

It's going to be reading slow. You will be going faster than you think. Pretty obvious if you think it through.. the gauge reads by measuring revolutions of the wheel at the hub, it has no idea of the circumference.

17" has a circumference of 54" roughly & 16" a circumference of 50" without the tyre. So it should be about 10% difference (for every revolution you will be travelling an extra 5"+ than the speedo thinks you are). That's not precise because of tyre profiles etc. You need accurate diameter measurments on both wheels with the tyre mounted to be sure.

Dan

Makes a lot of sense ... and if you swap a 17-inch wheel on a GS that had 19-inch wheels, the speedo would now read faster ... but you would be going slower than indicated.
Thanks for the insight!

[jwhelan65]

another pic

just another pic..

[saffa]

looking good....gonna be a cracker when its done .....lots of attention to detail.

although i was never a fan of that clock pod ...a little too informative and bulky. they did have some strange ideas back then.

[posplayr]

gonna be a cracker when its done

Oh no dont use that word some of us white folks will be offended.


Sorry could not resist after reading the other "Jap" thread.

Looks like you making good progress Joe. I'm gonna be starting mine backup soon as well.

Jim

[Ogri]

finally got to put these on, as soon as the ends are mounted they should really set the bars off.

Your bike is looking fabulous! I love those grips too.

[quexpress]

Sweet!!! What kind (model) of handlebar is that?

[jwhelan65]

Sweet!!! What kind (model) of handlebar is that?

Yamaha FZ1 (Gen II 2006-2009)

[Colorado85gs550]

When I switched to the 17" front wheel I found the stock speedo was off by close to 10% on the low side.

this was going from 16 - 17 right?

[Colorado85gs550]

I'm going from 100/90-16 to a 110/70-17.....

how do I figure out total difference......is there a calculator/equation to use?

[Billy Ricks]

this was going from 16 - 17 right?

Yes, the original tire was a 16 and I went to a 17. Measure the circumference of both tires and see what the ratio is. Bike speedos are usually off a little on the high side so the actual difference may not be as great as what the speedo is registering. Best thing is to have someone is a car hit a designated speed then signal you when they hit that speed and see where you're at.