Road tests of the era give numbers to speedo accuracy.
About 4 or 5 mph out at 60 mph was common.
Jagbruno said:Well the problem is that at high speed/revs, the needles on both of them tend to wobble quite a bit...during my circuit experience 2 weeks ago, at the end of the Dijon straight, slightly uphill, my speedo was indicating anything between 120 and 135Mph while simultaneously, my tacho was showing 7000/8000 RPM...obviously, my bike is a Featherbed with a moderately tuned engine in it, no isolastics, full Dunstall fairing, Dunstal box section extended swingarm, lightened crank and rockers, PW3 camshaft.
Fullauto said:Remember that the Smith's speedo is adjustable. You can get them as accurate as you need to.
Rohan said:Fullauto said:Remember that the Smith's speedo is adjustable. You can get them as accurate as you need to.
On the bench.
The aforesaid vibes, even from less than smooth roads will still give some needle jitter.
Especially at warp speeds, Mr Spock.
And its not exactly a simple DIY adjustment either, is it. ?
You have to destroy the chrome bezel ring just to be able to get into them.
And be able to satisfactorily neatly crimp a new one back on.
The idea too of speedos slightly over reading is that assists in keeping road users UNDER the legal speed limit,
rather than over it....
Fullauto said:Incorrect. The adjustment is through a hole on the speedo's base. You can get at it with a small screwdriver.