Speedo and Tach dissection with pics

go to xj4ever.com, schmuck keeps them parked there

 

I hate to dig up an old thread...... But I have an issue with my tach squealing like a spun bearing.

I've disconnected the cable to my tach since it started. I have not torn apart my instruments yet. Do any of you think this is all I need to do in order to resurrect my ailing tach?

 

i had an issue trying to get the needle off the tach as it snapped in half, so now i just have a stub. i tore down and replaced some insides with different ones because i have an electronic tach and the haynes manual says nil about it (so frustrating) and i bought a gauge cluster for a "1982 yamaha maxim 650" but of course when i got it it had the tach for a cabled system so that was great. i couldnt get the needle off, and slightly bent something i think because the needle now rests initially just under the 0, so im always slightly off. not taking that dang thing apart again. just dealing with it until i can figure out some other gauges. frustrating to say the least.

 

I could put it up on Chacal's site, but it's up to Fitz to decide whether he wants me to do that or not. It's his writeup, after all.

Not Fitz's, I don't. Need permission first.

 

Schmuck, the link to my "how to" still works, it's this article right here.

The link he's talking about is a link to the site you don't use anymore; a PDF entitled "speedometer breakdown." All of my stuff is still alive right here on this site; we haven't converted this one into a PDF yet that I'm aware of.

 

That much is obvious. What I hadn't noticed was that the post I replied to was 13 months old.

I had; hence the link.

 

Hey I was wondering if someone could share some insight, with me. My speedo isn't working but the odometer is and we took it all apart and it looks exactly like the picture. Everything is moves and isn't stuck the magnetic head "B" spins but its not spinning the shaft cup. I can move the shaft cup and everything else moves above it. Its hard to see what is going on in the shaft cup because of that bar, Anyone it would be a lot of help I'd rather try to fix it then get a whole new instrument custer and maybe have the speedo not work again lol

 

The cup spins independently.... Now when I say that, keep in mind that it spins at a different speed too--- it seems to spin at a different speed to create the relative drag (magnetically, if I remember correctly) to calibrate correct speeds

 

The cup doesn't "spin" it does rotate to move the needle.

It rotates in response to the spinning magnetic head "dragging it along" via magnetic pull.

If the magnetic head is spinning but it's not moving the cup, it has likely lost most of its magnetic properties OR the cup/needle shaft/bearings are so gummed up it can't move in response to such a light pull.

 

That's exactly what I was trying to describe.. " Slowly Rotate" is a better way to say though. Maybe even better-"slow rotation acting as a damper"
Dave

 

Correct.

The actual damper is the clock-spring. Which is why (if it's been apart) initial needle position is uber important since the preload on the spring is what resists the needle from slamming the peg on the top end as soon as the magnet spins, plus the needle itself is the "downstop."

However, I failed to mention that if someone before you had the instrument apart it could have been incorrectly reassembled.

If it is indeed an original part, I'm betting it's gummed up over anything else.

 

On some models the needle stops against a very small plastic pin that sticks straight out from the face.

 

None of the links seem to work, unfortunately. I'm having a difficult time with my speedo, and came here for help. It's whining, vibrating, and having a terrible time! I had to unhook it today, just to get home. But I would love to be able to fix it without taking it completely apart - is that possible??

 

Katherine, it depends on which model of bike you have. Some are easy to open up, and others are labor intensive. Let me know the following:

1. what bike you have
2. where you're located

If you're close by, (I'm near Utica, NY) I could possibly help show you what to do....or you could send it to me and I could go through my parts and see what could be replaced; or you could just get a replacement from Len Chacal, or ebay, or etc.......

As far as links--we just went through a complete migration, and we are still working on getting things back up and running. Much of the info is still on the old server and has not been all brought over yet.

Dave Fox

 

Thanks so much, Dave!

I have an 85 Maxim X, and am located near Anderson, Missouri (a bit too far from you, unfortunately).

I actually took the speedometer off, and tried to clean it up a bit, and put it back on the bike. It then worked for about 4 hours before the whine came back! I'm pretty sure I need to get into the case, though, but I'm a bit nervous about getting the bezel off and back on.

Once I got the speedo off the bike, I found that I actually had a broken reed switch - do you know where I can get a replacement for that? The glass is broken, as well as the plastic holder for it. I have made it a habit to cancel my turn signal, but I would really like for it to work again!

I've looked over your illustrated article, "Gauge the results for yourself", and find it absolutely wonderful! Thank you for the in-depth guide. KUDOS to you!!

 

You're welcome! Yeah, if you have an X, then that is the only day to get in there shy of cutting the plastic in half. For the Reed, contact Len Chacal at xj4ever.... That's who I got mine from......

 

Well, I've done it now!!

Tore into the speedo, and cleaned it up a bit. It seems everything was fairly functional, just a little gummed up. I seem to be having the most problem at the input shaft. It was a bit difficult to turn, and since I've cleaned it out some, it seems a little "loose" - is that how it's supposed to be? I've been trying to clean it out (as best I can), and when I have the cleaning solution in there, the shaft spins easily. Once I spray it out with the compressed air, then let it sit awhile, it is difficult to turn again. I have not yet tried to lubricate it, as I want it to be thoroughly dried out. Suggestions???

Also, I have looked for a lubricant similar to one you have pictured in this thread, but couldn't find anything with teflon. I found a silicone spray with "cerflon" (Liquid Wrench product), and after doing a little searching, found that this new ingredient is similar, and I think I read that it has teflon in it. Have you ever heard of this? Would this be a good lubricant for this application?

 

If you're gonna try to spray some lube in there, look for a white lithium spray grease.

Dave

 

I've updated most (98%) of the links to some of the most relevant "how-to" or useful threads, please visit:

http://www.xjbikes.com/forums/index.php?threads/the-information-overload-hour.27544/

and, of course:

http://www.xjbikes.com/forums/index.php?forums/xj4ever-supporting-vendor.23/

 

Excellent write up BigFitz - I have taken my speedo apart several times due a few unfortunate issues like that squealing others have noted (during low speeds and cold weather). Both my needles decayed from age and have been replaced with toothpick substitutes, but now that I have a decent low mileage replacement speedo/tach unit my question is - is it possible to swap in the original odometer? I'd prefer to have the original odometer reading (85,000 and counting) for accuracy's sake.