Topic: Speedo help question

[Johnie]

Current project 78 CB550K - got this really clean speedo with only 9,700 miles which is in great looking shape. Last run 2 years ago. This is the first bike I have had an issue with the speedo running slow. I put it on a test with drill and the miles and trip run fine. The needle is sluggish both up and down. I hate to pull this apart if possibly a little squirt of PB Blaster or WD40 up the shaft might loosen it up. Anyone have this issue and remedy it?

[flybox1]

If pb blaster gets in those gears, you may have stains on the gauge face or inside glass.  Then a full teardown is needed.

Pour in some Isopropyl alcohol.  4-5 oz....Slosh it around.  Drain it out.  Repeat if necessary.
Wont hurt the gauge faces You might be surprised what comes out.
Place over a heat register to dry it out.

[Johnie]

Flybox...do I have this right. Take like a syringe and squirt it up through the shaft hole. Then let it run back out. But I take it I do not want to turn the speedo upside down as the alcohol and dirt might run onto the interior of the face.

[flybox1]

I poured 4oz into the hole the light bulb fits in (not the speedo cable hole) to rinse out any dust inside the gauge body and on the speedo gears on my 350F.   No harm to the gauge.
Pouring it directly into the cable hole might open a can of worms.  I dont think you can get it to 'return' to zero faster