Another Speedometer question

[Frank @ TX]

I have an MC-9 and the speedometer always reads about 7 miles / hr too high.
I checked it many times against mile posts and other cars driving beside me.
It has a magnetic pickup at the front tire.
Is there a way to make adjustments to the speedo head??
Thanks
Frank.

[TomC]

More importantly-what does the odometer say?  For instance-my speedo reads 4mph slow, but is only 1% off in mileage (I loose 1 mile per 100 miles-so I think that is pretty close).  Good Luck, TomC

[Lin]

If yours is like mine, there are two small brackets, 180 degrees apart that rotate past the pickup.  You can calibrate the speedo by increasing or decreasing the space between the bracket and both pickups.  I do not remember which way does what anymore, but I do remember that Bill at US Coach said they set the space using the thickness of a 3/8 washer.

[steve5B]

  My GPS says it's within 2 MPH + OR - Everyone that i know say the same thing on theirs too!  Guess industry standard!

  My 2 pennies worth!

   Steve 5B.........

[Busted Knuckle]

If yours is like mine, there are two small brackets, 180 degrees apart that rotate past the pickup.  You can calibrate the speedo by increasing or decreasing the space between the bracket and both pickups.  I do not remember which way does what anymore, but I do remember that Bill at US Coach said they set the space using the thickness of a 3/8 washer.

I always used a "nickle" ! That way I knew it was good for doing the "double nickle!" LOL!

Actually I'd usually borrow a nickle from the owner or bystander, and when done I'd pocket it and make myself a nickle tip! 
  BK   

[Ncbob]

Frank, don't know if you have a tachometer but that's how I run my  bus. The GPS, or my wife in the car with a CB radio tells me when I'm running 60 MPH. Then I go from there. At 1750, a speed  Detroit's like, I'm doing 60 so I don't even watch the speedometer which I KNOW has a 10% error.

NCbob

[Frank @ TX]

Hi NCbob,
Yes I have a tach and a 5 speed man and a 6V92.
I do go by the tach to help me stay at speed.
When I installed the tach I checked it with a photo tach as a master.
I travel at 1600 to 1700 rmp and the engine just purrs real nice.
But it still bugs me that the speedo is off by so much, I use the odometer for the MPG info.
I was hoping that there was a way to fine tune it.
Thanks for the info
Frank

[JackConrad]

I have an MC-9 and the speedometer always reads about 7 miles / hr too high.
I checked it many times against mile posts and other cars driving beside me.
It has a magnetic pickup at the front tire.
Is there a way to make adjustments to the speedo head??
Thanks
Frank.

Might try making the air gap just a little larger. Also check for any rust particles on the magnets as these can create a narrower air gap.  Jack

[Frank @ TX]

Thanks Jack , I'll try that.
Frank