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masterofpuppets
29th January 2007, 19:09
hello people,
just recently managed to get the old cb250n on the road, cruising around at 50 the other day, found myself having to overtake everyone. drove to one of those acc speed things, and it says im doing 55 when my speedo says 45.
any ideas as to what could be the cause the cause of this???
when i got the bike it seemed like someone had "oiled" everything with chain oil :nono: :nono: . i cleaned all that up, but now it reads high....

any idead would be appreciated....
also not sure if this is in the right section, so please feel free to move it if you wish

tl_tub
29th January 2007, 19:14
I could be proved wrong, but as far as i am aware, those acc speed measuring signs are not calibrated to a traceable standard.

cowboyz
29th January 2007, 19:16
thats not that far out. I doubt spreading oil everywhere would have made a difference. Bikes are optomistic with speed anyway. Things like changes tyre profiles have massive effect on speedo readings. Just work out 50, 80 and 100 and know your bike.

Nasty
29th January 2007, 20:20
We had major under issues when I was learning .... Grub rode the bike while i drove the car at specific speeds to work out the varibles at 50 and 100 .. was 55 and 110 .... it helped a lot knowing how much out I was.

merv
29th January 2007, 20:27
Check riding at a constant speed with a GPS is the way to go.

tl_tub
29th January 2007, 20:36
Dont rely on GPS for speed.. its been proved to be inaccurate in some situations by more than 10kph