1991 Honda Nighthawk 250 Speedometer Broken

Hello!

I have a speedometer that stopped working a few weeks ago and I can't
figure out whats wrong. I have replaced the cable since it stopped
working, but it didn't fix the problem. Any other ideas of what it
might be? The bike is a 1991 honda nighthawk 250. Any help would be
much appreciated!

Thanks,
Carrie

 

The cable might not be seated properly in the drive unit on the front
wheel.
Or, the drive unit may not be operating properly.


Wudsracer/Jim Cook
Smackover Racing
'06 Gas Gas DE300
'82 Husqvarna XC250
Team LAGNAF

 

Find a way to get the front wheel off the ground. With some
motorcycles, you can put a piece of a wooden 2 X 4 under the center
stand and that will get the front wheel off the ground. You might need
a friend to hold the rear wheel down so the front wheel is off the
ground.

Disconnect the upper end of the cable from the speedometer and spin the
front wheel. If the cable turns, the speedometer is probably broken.

If the cable doesn't turn, disconnect the lower end of the speedometer
cable and spin the front wheel, watching the hole in the speedometer
drive. If you don't see a little gizmo turning, the problem is the
speedometer drive.

Try to slide the speedometer drive unit sideways on the axle. There
really shouldn't be much sideways motion, maybe 0.01inches or less.

If the speedometer drive slides sideways a lot, somebody who changed
the front tire may have installed the front wheel improperly and the
tangs on the speedo drive unit aren't engaging the wheel.

 

The cable might not be seated properly in the drive unit on the front
wheel.
Or, the drive unit may not be operating properly.[/QUOTE]

It's usually fairly easy to check the drives (at both ends of the
cable), visually. The socket in the drive should be the same shape as
the cable-end. If it's chewed up, there's your problem. If it's the
speedo socket that's chewed up...well, there's always the Sigma bicycle
computers.

--
Later,
John



'indiana' is a 'nolnn' and 'hoosier' is a 'solkk'. Indiana doesn't solkk.

 

It could be a problem with the wheel drive. Suzukis have a plastic piece
that can break when you're not careful putting the wheel on (or they can
just break forthehelluvit) - I haven't dealt with Hondas in a while.

If you put the bike on a front stand and spin the wheel, or push the
bike around and watch the cable end, and the cable doesn't spin, that's
the problem area. This is cheap and easy to fix, so you hope this is so.

It could also mean you got a brand new broken cable, or the cable isn't
fully seated in the square hole in the wheel drive. Both have happened
to me.

If the cable spins, then the drive hole in the instrument could be
rounded, but I doubt it. There's a magnet that the cable spins inside
an aluminum cup attached to the needle, and drags the cup (and needle)
around by magnetic eddy current effect thingies.[1]

Anyway, I've had the magnet shatter. I've had the bearing for the magnet
break so it's out of position. I've had the aluminum cup bit seize up.

This usually means the instrument itself is toast, which is expensive.
You *can* take the thing apart and fix it if you're an aspiring
neurosurgeon, but it's real iffy.

However, I've never had the instrument die without cause, like dropping
the bike or something.

Good luck.

-gc

[1] can I vague that up for ya?