Topic: CB550K1 Speedo Trip Reset Knob

[saxamaphone]

Hi guys, I'm taking my speedometer mostly apart because the needle is sticking at 20mph.  I've read a number of threads about taking them apart as well as some good guides http://www.salocal.com/sohc/tech/speedo/spedo2.htm and http://www.dimecitycycles.com/dccdiatribe/2011/02/honda-cb-gauge-disassembly-and-face-replacement/.

I'm wondering if anyone knows how to take off the trip reset knob?  This model has it on the back.  I think there is supposed to be a set screw in the knob but mine doesn't have one. My understanding is that the knob should pull off once the set screw is out but mine is held tightly in.

[saxamaphone]

If anyone ever has this question, I just figured it out.  The 550K1 trip knob on the back should pry off if the set screw is out/missing.  Mine was stuck and needed some more force is all.  Didn't want to damage any of the delicate parts in the speedo.

Now hopefully a clean and some lubrication will fix the needle.

Cheers

[RAFster122s]

There is a thread on the boards about replacing the dampening fluid in the reservoir that the spring attaches to which the needle is attached.  I don't think I am confusing tach and speedo construction, but might be. The silicone fluid can be bought online or sometimes at hobby shops specializing in rc cars.  You drill a hole, refill, and seal hole with few drops of epoxy or similar.  This is often needed if the needle is swinging about at speed or doesn't rise and fall fluidly as they are designed to do.
Thought I would mention it since you have it apart.

David

[saxamaphone]

Hi David,  thanks for the info.  I ran across a few of those threads about that fluid.  I was thinking I might have to do that but I found the problem of why the speedo was sticking at 20mph.  It wouldn't even go down or up from there.

The metal bit that half covers the magnet was rubbing against it at certain points of the rotation.  When the cover was removed, the needle turned smoothly and easily.  It was like new inside the speedo, very clean.  I found that if I simply pushed up as I screwed in the magnet cover, it left enough clearance for the magnet to move smoothly.  I rode the bike for a short trip around the neighbourhood and it worked perfectly. 



This is about where the two parts were catching:



Now I'm having trouble getting the housing back together.  Seems like the metal ring you crimp won't reach over high enough anymore for me to crimp it down.  Maybe I pushed it down a bit when removing.  Not sure.  I might clamp the housing closed while I do it and hopefully gives me some room to play with.

Now for the tach.  It goes to 3k and stops there.

[RAFster122s]

You do know about CycleX's repo tach & speedo don't you? Just so, you don't spring for a set off ebay.
Some guys put a small bicycle speedo on their bikes and kind of only have the stock units there for looks.
Then there have been some enterprising fabrications of melding the bike speedo into a stock tach eleminating the speedo.  Have not seen anyone take a large VDO electronic tach and transfer the guts into the cb550 or cb750 housing. The later Honda electronic tachs can be used but the faces and fonts are different so it requires some acceptance of the lack of esthetics or some dissassembly to replace the faces, redo the faces.