Speedo Error with Darkside ?

[TourNut]

Has anyone noticed if the built-in Honda speedo error got better or worse with their CT , please indicate which CT you have on & psi you run , Thanks

 

[SMSW]

Measure the circumference of your previous tires and that of your darkside tires. Then do a little number crunching. If the circum. of the new tires is less than your original mc tires, the bike will go a shorter distance for every revolution. The speedo gets signals off the crankshaft so the bike will go less far for an indicated mile than before you mounted the car tire.

 

[Al st1100]

Measure the circumference of your previous tires and that of your darkside tires. Then do a little number crunching. If the circum. of the new tires is less than your original mc tires, the bike will go a shorter distance for every revolution. The speedo gets signals off the crankshaft so the bike will go less far for an indicated mile than before you mounted the car tire.

speed sensor on trans output shaft 205/50/17= 25.1 diameter, 832 rev per mile 170/60 17 = 25 in diameter so the speedo should be really close

 

[W0QNX]

The speedo is off by 5 anyway at 70, no difference noticed with various car tires.

 

[rhjiii46]

The speedo is off by 5 anyway at 70, no difference noticed with various car tires.
[/QUOTE

Gen 1 GL1800's speedo's were off by 5+ MPH so I ran a 205/60-16 instead of the much more common 195/55-16 (which is almost identical in diameter to OEM 180/60-16 bike tire) and my speedo was less that 1% off. SO.....size DOES matter.

Here's a tire size calculator: https://tiresize.com/calculator/

 

[rhjiii46]

Here's a bike tire in a size that should correct the speedo:

Bridgestone Exedra G850R-G 190/60R-17 78H Rear Motorcycle

America's trusted online source to shop the best discounted Motorcycle, UTV, ATV, Side by Side, and 4 Wheeler aftermarket tires, gear, parts and accessories.

www.americanmototire.com

A 190/60-17, anyone tried this?

 

[leonides]

I notice a 5 miles difference from the ST speedometer and the GPS.
Is there any electronic adjustment that can be made to correct this?
Thanks

 

[Andrew Shadow]

Is there any electronic adjustment that can be made to correct this?

Adjustment to any of the OEM components to correct the speedometer- no.
You can correct the speedometer reading by adding something like a SpeedoHealer but, doing so will throw the odometer off.

 

[spiderman302]

If you do not have a GPS to check your speed odometer, there is a free app for your phone called DigiHUD that will give you a large display of your speed.

 

[rhjiii46]

the 190/60-17 mentioned above has a 26" circumference. The stock 170/60-17 is 25". That's a 4% diff and should tale out most of the 5mph error in the speedo.

Speaking of larger diam. I posted this on GL1800Riders - "Free rear tires for life" (link)

Free rear tires for life?

I just posted this generically (tire type wise) on the general board but thought I'd post here with more detail re: car tires. I just finished a 4750 mile ride from Sacramento to explore northern Washington state and southern BC Canada. Two things got me to thinking about keeping track of my...

www.gl1800riders.com