Topic: 1976 honda 750f1

[Gunga]

Anyone have any ideas why my speedometer shows 10mph faster than my actual speed.  I also am wondering if anyone out there has a left sidecover with emblem for a 76 750f1.  I live in MN

[krusty]

How have you determined that it is out?
Checked against a GPS have we?
Incorrect tyre size?? 
Incorrect speedo drive?
Or dodgy speedometer?

[Gunga]

Radar sign that posts my speed is how I checked my speed.  I also get passed on the highway by everyone when following the speedo.  My tires are the correct size and my speedo is original.  Something could be wrong with it I suppose.

[Steve F]

They're supposed to read faster than actual speed, that's the way Honda designed them, but 10 over is a bit much.  There are people out ther that can re calibrate them but it's NOT cheap.  It involves cutting them apart to open them up for service.  I would suggest you find a replacement and try it.
Oh, and those radar signs aren't that reliable.  Buy or borrow a GPS and see what your speed is with one of those.

[Hon3ybadger]

Yes GPS is the best route. Unless you drive in tunnels. The quick and dirty trick I do is find a newer Honda civic and look through the driver side window at the giant digital speedo they have. Match your speed with them and compare gauges. I found mine wiggles three to six mph faster than their speedo says. And its tested against many civics. Tire size is 100/90/19

[flybox1]

Radar sign that posts my speed is how I checked my speed.  I also get passed on the highway by everyone when following the speedo.  My tires are the correct size and my speedo is original.  Something could be wrong with it I suppose.

does the speedo needle rest against the 'zero' post on the face, or does it hang up a bit higher?
someone might have been inside the gauge and attached the needle in the wrong spot.

[Markcb750]

Showing higher than actual is a common condition, sometimes cleaning & lubing drive cable will help, but not a lot. 

Mine reads 52 at actual 45.

Until I 'calibrated" it people were passing me all the time.

[Duanob]

A lot of people put bigger tires than stock, me included. that will throw the final drive ratio off a bit.