figure this one out

[steve kearl]

Does anyone have any ideas? I have been putting stainless steel bolts on my S4 and changed the rear disc bolts to stainless, but when I rode up the road I found the speedo was not working. I know the speed sensor works off the back wheel and obviously the disc nuts because when I put the original nuts back on the speedo worked again and I know that stainless steel conducts electricity because I did a simple bulb test with one off the nuts.
Has anybody got any ideas or has anybody else changed their nuts with better results?

[steviej]

MMMmmm...........Non-Magnetic?? :confused: :confused:

[Albie]

Hmmmmm!!!!!!!! :confused:

[NBs]

Yep, as steviej says, it's a magnetic pickup and the stainless bolts obviously don't have enough iron content. Or maybe they protrude less than the originals so are too far away from the pickup?

[DesmoDog]

could you put regular steel washers in? Might give you just that little bit more magnetic field - or could you magnetise the stainless bolts? Or is that a daft idea?

[BoozyBOB]

stainless steel comes in different grades..most are non magnetic..(but you do get a stainless that is magnetic, i will check at work)..as for steel washers..this can cause a reaction with the stainless and a corosion that can destroy everything in contact :eek: ...

[DesmoDog]

Argh, yes I remeber reading this somewhere else. What happens when we use stainless bolts in our engine blocks etc?

Dog

[Pedro]

Couple of things:

See the Disc Bolts thread and Dom's comments. Stainless is a no no for brakes!

It's also non-magnetic as Stevie J said so the pick up won't work - it magnetically activated.

Stainless bolts into ally is ok if you coat them in anti-seize compound

Ped

[steve kearl]

Thanks people for your input on the rear disc bolts, it is because they are non magnetic and you can get magnetic stainless steel but it is less anti-corrosive and they would have to be made and the minimum order Inox would need would be a hundred.
thanks again people