Faulty speedo

[LisaW]

Hi all

I got my 'new to me' m600 about a month ago. We have since been tarting it up. However, on its only trip out, it was noticed that the speedo was not accurate and running too slow. What is the likely problem and how do I rectify it? Any suggestions?

Thanks in anticipation............

Lisa:on:

[bigfiretruck]

it could be a slipping cable...... make sure they are fully connected both ends

if i slam my front brake on hard enough i can get the speedo to read 0 even tho i clearly moving

[PhilLew]

Mine under estimates speed by about 10 - 15% as well.

I've checked the cable and everything seems fine so I'd be interested in anyone elses ideas/coments.

I though it was just mine until I saw this thread.:)

[Nickj]

I think the mechanical drives use a magnet as a part of the drive, this looses a bit of its field over time so gets to reading low. Clocks usually do run low if anything in any case.
You need the thing adjusted to get it back to closer to real speed.

[LisaW]

Thanks for the help, how do you adjust it?

Thanks Lisa

[singletrack]

Also check the wheel/tyre sizes if the rear oe has been changed it will read differently.

[Nickj]

It needs a man with a tool Lisa. They check the magnets field strength then see where the needle goes at a fixed input speed. Then calculate what the strength needs to be and either mod the magnet or its clearance height and recheck that the change has made the difference required.
Defo not a kitchen table job

[PhilLew]

Clocks usually do run low if anything in any case.

I thought they weren't allowed to run low (under estimate the speed) but could and usually do over estimate?

[PDL]

Mine is bang on, I went past one of them digital road sign warning things last week which started flashing and it stated that my speed was.....

































******The rest of this post has been deleted*********



...which incidently was the same as my speedo.

[bigfiretruck]

yea but those speed check signs over estimate! they will say 31/2 when your doing 30 just so that you DONT get done for speeding!

[LisaW]

Man with a tool, I like the thought of that, where do I find one???

[Nickj]

Try these guys??
http://www.jdo10.pwp.blueyonder.co.uk/page2.html
Worth a call at least