Topic: CB550 RPM issues

[seanbarney41]

I got a messed up 550 tach that you can try as a comparison.  It generally works but the needle bounces kinda bad...cam be yours for shipping...

[FunJimmy]

These are forty year old POS bikes. The tachometers weren't that great when new and 40 years later the lube gets old and crusty. Should be amazied that it works at all.

Pull the tach cable and remove the inner drive cable.
Discard and reinstall cable. Ride!

You'll learn when to shift and when the bike is over revving when it no longer produces power.

[natron602]

You had the same tach before the rebuild and it worked normally?

Nope. Same problem before the rebuild. Kind of hoped it would be solved. Replaced gaskets and o rings cleaned and lapped valves cleaned cleaned cleaned and painted. The timing and carb sync are left on my list but can't think of any reason those would do that.

Is that an oreo cookie in your hand?  Those go in your mouth, not a 550 engine!

Damn. I knew something wasn't right...

[natron602]

I got a messed up 550 tach that you can try as a comparison.  It generally works but the needle bounces kinda bad...cam be yours for shipping...

I appreciate it! I'll take you up on that if the new cable doesn't do it.

[natron602]

Double check that tach drive gear is properly and fully seated, and that the securing screw is in place. Also, check the screw/bolt that holds the housing to the cover.

When you rebuilt the engine, did you inspect the gear. Perhaps the teeth are badly worn or the inner seal is. At higher speed, it may be "floating" out of engagement with the cam gear.

Then again, as FJ said, they weren't great 40 years ago, and still aren't.... But they should behave better than yours is currently.

B best answer yet as it gives me info on the specifics of what could be going on. Played this morning a bit. The housing is secure but there is some play in and out at the engine side. Not sure I if that's normal or the seal being bad or even a missing washer or spacer or something but that gives me a place tto look while waiting on a cable which I still need to measuure and order..

[flatlander]

here's a diagram of tach gear and housing, to see if you have everything:
http://images.cmsnl.com/img/partslists/honda-cb550k3-four-general-export-mph-cylinder-head-cover_bigma000085e01_b6cf.gif

you can find diagrams of everything else also on cmsnl.com.

[Lostboy Steve]

These are forty year old POS bikes. The tachometers weren't that great when new and 40 years later the lube gets old and crusty. Should be amazied that it works at all.

Pull the tach cable and remove the inner drive cable.
Discard and reinstall cable. Ride!

You'll learn when to shift and when the bike is over revving when it no longer produces power.

wait..... what?

[natron602]

How do you measure the cable? It is just the vinyl cable part or do I include any of the gears or mounting parts? I have (I believe) superbike bars and my measurments seems about 24" and 27" is the shortest I'm seeing for the CB550.

[natron602]

Ferrule to ferrule is your overall length.

Thank you (pretending I didn't have to google "ferrule")!

[goldarrow]

Roll up your old cable and put in small container, pour in wd40 and let the cable soak overnight....

[goldarrow]

Roll up your old cable and put in small container, pour in wd40 and let the cable soak overnight....

Not terribly effective at lubricating a cable. WD-40 is for anti corrosion applications, not lubrication. If you want to properly lube a cable, use cable lube or spray lithium grease (worst case). But WD won't last and soaking the sleeve does zero for proper function. 

Wd40 is great for cleaning, it's only part of the process. 

[FunJimmy]

If WD-40 doesn't work, try duct tape.
Those are the only two solutions in the world.
One must be correct.

[natron602]

I had it patched with bubble gum but I think I used the wrong flavor.

[goldarrow]

If WD-40 doesn't work, try duct tape.
Those are the only two solutions in the world.
One must be correct.

or

These are forty year old POS bikes. The tachometers weren't that great when new and 40 years later the lube gets old and crusty. Should be amazied that it works at all.

Pull the tach cable and remove the inner drive cable. READ: DITCH THE CABLE
Discard and reinstall cable. Ride!

make up your mind...and pick one

[goldarrow]

If WD-40 doesn't work, try duct tape.
Those are the only two solutions in the world.
One must be correct.

The DIY-ers remedy for anything!

let's pay someone to do this for you, let's replace the dang thing...oh wait, let's help stimulate the economy, like we all have loads of cash laying around.  let's tear down our garage and shops and pay, pay, and pay up for always something new and someone to do it for you  

[natron602]

So uh... the oil seal is an optional part, right?

[goldarrow]

Be careful when you put that cap back on.  People break these thing, and it's discontinued from honda. 

Some guys might tell you to ditch that too and use plug to plug the hole, then spend $300 on electronic tach, cuz this dang thing is 40 yrs old. 

Some guys may also tell you to take it to professional installer and pay up $100 labor and have it done for you.  Since you're a DIY, your work may be sub-standard

[natron602]

Be careful when you put that cap back on.  People break these thing, and it's discontinued from honda. 

Some guys might tell you to ditch that too and use plug to plug the hole, then spend $300 on electronic tach, cuz this dang thing is 40 yrs old. 

Some guys may also tell you to take it to professional installer and pay up $100 labor and have it done for you.  Since you're a DIY, your work may be sub-standard

I'd like to think of my work as barely standard.

[natron602]

I like you guys.

[natron602]

So I uh... Took the tach off...started taking it apart...couldn't figure out how...decided to save it for the weekend...put it back on....start her...it jumps around like a tweaker in a mosh pit... but if I push on the stem where the cable screws in.... hey, now it idles at a smooth  1200 too...

[goldarrow]

If WD-40 doesn't work, try duct tape.
Those are the only two solutions in the world.
One must be correct.

The DIY-ers remedy for anything!

let's pay someone to do this for you, let's replace the dang thing...oh wait, let's help stimulate the economy, like we all have loads of cash laying around.  let's tear down our garage and shops and pay, pay, and pay up for always something new and someone to do it for you

No one has suggested your litany of pursuits, simply to not use WD-40 to lubricate a cable. That was your advice to soak his cable in it. Then you said, "it's part of the process" but failed to mention what other parts/steps follow or precede that step.

Pretty sure FJ was having a laugh (everyone but you seemed to get it). Take some more Xanex and have a soak in tub of WD-40 (it's part of the process).

may be Xanex is actually more suitable to use on you???  I had only merely suggesting the OP to

First to do Clean or replace tach cable, cheapest option

come on calj, I thought you were smarter than lubricating the cable with wd40,  or wait, you can't read or comprehend simple words, may be you need to it to clean your brain a little???

[natron602]

It's cool. I didn't do any of that #$%* anyhow. I just started taking stuff apart.