Dissamble tachometer

[clyde the ape]

Hey everyone, I'm wondering if I can dissamble the tach & speedo on my 79 750ltd.  I think they work, but the needles are hitting the clear cover & wont move freely.  The tach hangs up & has to be tapped back down.  I think if I can "adjust" the needles I may be good.  But how do I get the damn thing apart???

[shinyribs]

I've never seen DOHC gauges ,but on the earlier ones the needles are a long ways from the lens'. The early (SOHC) gauges have two nuts on the back side that if they are loose will cause what you are describing. Might check there and see what you find

[Piute]

   10lb. sledge

[sgtslag]

They can be taken apart, somewhat.  I pulled mine off, several years ago.  I don't remember details, but I do remember the book warning me not to turn them face down, or they will leak fluids, ruining them.  I know, I've had this discussion before:  it's damping fluid, but beyond that, I don't have a clue.  From what I do remember, I just pulled them off, and then I was able to figure out how to pull them out of their housing.  Sorry, can't remember details, but it wasn't terribly difficult.  Try checking the FSM, found on the Home Page of this site.  It should discuss the topic.  Cheers!

[eric moon]

Hi Clyde, I took one of mine apart just a couple of weeks ago because the needle had broken prior to my getting the bike. You have to 'nibble' around the rim ring starting off with a knife or very thin screwdriver. Gently prise the rim away from the body working round at very small intervals until completely round the rim. The rim will then just prise off the body. There is no fluid in the dohc type to worry about. I tried to prise the needle boss off with two small screwdrivers but it was so tightly onthat i actually pulled the pivot pin right out!
I havent tried to repair it as i cant get a replacement needle anyway. The clock was broken anyway and i had a spare so its just sitting in a box for now. I may revisit it at some point.
Be careful with the needle, they get very brittle!

[clyde the ape]

I tried prying with a screwdriver. I can't get it to budge, how hard to I have to pry?  Are you working on the face of the gauge or from the back?

[seestheday]

Don't know how much this will apply to our tach/speedo, but here is a how to refresh a speedometer from chopcult (not cb750 specific): http://www.chopcult.com/forum/showthread.php?t=1611

[clyde the ape]

Well I got my tach apart. (Thanks for the link sees)  But I managed to break the glass fml.  
Is this just a flat piece of glass??  
Anyone have a busted tach or speedo with good glass they would be interested in selling?? LMAO