[wazted]

1. What is the size of tire needed in order to spin at the correct rpm for the speedo to be dead on?

2. Why doesn't everyone just buy that size? :shrug:

Probably once I hear the answers it will be apparent..right now its just a puzzler.

 

[Larry Price]

I have grown a custom to just using my GPS for my speed, if not that, then I just keep pace with the surrounding traffic. The problem with trying to constantly dink around with speedo correction is it does not correct odometer errors. If you mess with one, it screws up the other. So the heck with all of it. Just ride.....

 

[Murgie]

A big advantage to using a CT is the runflat technology. Most if not all the larger size that help correct the speedo are not a run flat. Of course, this is just my opinion.

 

[JohnACman]

I have grown a custom to just using my GPS for my speed, if not that, then I just keep pace with the surrounding traffic. The problem with trying to constantly dink around with speedo correction is it does not correct odometer errors. If you mess with one, it screws up the other. So the heck with all of it. Just ride.....

:agree:

I gave up on trying to fix that thing long ago. GPS is always on the bike and dead on with the speed.

 

[storm]

I run a Kumho 195x60 and the speedo is 100% perfect according to GPS

 

[FrostyWing]

According to the tire calculator at http://www.discounttire.com/dtcs/infoTireMath.dos . A 195/65-16 would be 0.06" larger in diameter than a stock sized 180/70-16 tire. Now, finding a 195/65-16 is one thing......knowing if it will fit on the Wing without problems is another .
I'm quite happy with my 195/55-16 size but......I have a 28 or 29" inseam too! Besides, I don't ever check the bikes speedometer since I got the Zumo :yes1: .

 

[storm]

No 65 series will fit as the 60 just rubs the front right corner of the swing arm when new - I had to run mine against a die grinder for a bit to round the corner to fit. It is 3/4" taller than a stock MC tire of the correct size.

 

[richard h]

I use my GPS to tell me the correct speed. The speedometer is almost 5 mph off at freeway speeds.

If you really want a speedo that is telling you the truth, look into getting a speedometer calibrator. I will be getting a Dakota Digital unit at my next service when they change the air filter.

The calibrator has 2 buttons for bumping the unit up or down in fractions of a MPH. Easy enough to re-calibrate as the rear tire wears smaller.

This allows me to run the tire that fits and functions the way I want.



If you go to a larger diameter tire to correct the speedo, the calibration will change as the tire wears down. Probably not enough to make a big difference, but it will.

The larger diameter tire will also change your overall gearing. It will reduce your freeway RPMs by approximately 250 to 300. It's a pleasant little change but barely noticable.

Besides the freeway performance, if you tow a trailer, you will also notice a slight difference when you take off from a full stop. A little bit more slipping of the clutch is required.

So, you all have to make the decision as to what you like best. I have made mine for me.

JMO
:agree:

 

[storm]

If you think about it no vehicle is really spot on as far as speedo vs gps. All bikes and cars will vary slightly due to tire size and wear but what's 1mph at 65mph?
Who really drives the speed limit? - I figure if it's off 1mph the ticket will be slightly less.
Rather than spend a pile of money on a speedo recalibration unit - just buy a Garmin Nuvi 200 for $75 and you have correct speed and know exactly how lost you are.
Or when the time comes for a new tire just install a 195x60 and everything will be near perfect - as close a squad cars speedometer.

 

[richard h]

If you think about it no vehicle is really spot on as far as speedo vs gps. All bikes and cars will vary slightly due to tire size and wear but what's 1mph at 65mph?
Who really drives the speed limit? - I figure if it's off 1mph the ticket will be slightly less.
Rather than spend a pile of money on a speedo recalibration unit - just buy a Garmin Nuvi 200 for $75 and you have correct speed and know exactly how lost you are.
Or when the time comes for a new tire just install a 195x60 and everything will be near perfect - as close a squad cars speedometer.

:agree:

That is another viable approach.