K0 Speedometer overhaul
- Thread starter bc17a
- Start date
bc17a
Well-Known Member
Thanks HG,
I've learned plenty from you guys on here and am happy to give a little back.
Adam-NLV
Well-Known Member
Hey sport fans.
I got a 81' JH2 speedo that has some issues like high mileage and a dirty glass lens. I want to open it up and fix it. It works good with no needle bounce.
First off, this 81 is smaller than the K3 unit.
Second on the back it has some studs that the bolt is pressed or screwed into.
I tried to twist it to no avail. I'd hate to pry the trim open only to find it can't have the innards removed. Could it be in these later bikes the unit is truly tamper-proof?
Should i even try this because these ain't easy to come by. :39:
paid $32.97 for her.
Would luv to hear from someone that's opened a later model speedO.
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I got a 81' JH2 speedo that has some issues like high mileage and a dirty glass lens. I want to open it up and fix it. It works good with no needle bounce.
First off, this 81 is smaller than the K3 unit.
Second on the back it has some studs that the bolt is pressed or screwed into.
I tried to twist it to no avail. I'd hate to pry the trim open only to find it can't have the innards removed. Could it be in these later bikes the unit is truly tamper-proof?
Should i even try this because these ain't easy to come by. :39:
paid $32.97 for her.
Would luv to hear from someone that's opened a later model speedO.
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Adam-NLV
Well-Known Member
Ok, got through it with not that much collateral damage. The gasket tore and the inside flat blk collar-ring took a little paint chip but when it's assembled, shouldn't be an issue. The trim has pry marks on it and will easily disclose that it's been opened at one time but I don't care.
Interesting instrument. Guess I was expecting clock-like works but this is a neat balanced-out mechanism that's pretty well designed. The needle is carefully crafted and weighted (1.6 grams) as an integral part of the speedometer.
As far as turning back time (miles) on it, I'm not sure if that will be easy or hard. I'll tackle that manyana. i'm thinking this is gonna be the hard part but would take any guidance on this appreciably!
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Interesting instrument. Guess I was expecting clock-like works but this is a neat balanced-out mechanism that's pretty well designed. The needle is carefully crafted and weighted (1.6 grams) as an integral part of the speedometer.
As far as turning back time (miles) on it, I'm not sure if that will be easy or hard. I'll tackle that manyana. i'm thinking this is gonna be the hard part but would take any guidance on this appreciably!
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Adam-NLV
Well-Known Member
Some of it is dirt/grime but most of it is over-spray from the outer case being shot flat black!
As well known, on this 81 trail bike Honda omitted lots of the chromed parts from this model year and just painted em black, to save dough no doubt.
Some parts are still chromed on this 81, like the blinker stays front and rear.
ps...Now that you mention it, it does look like it could use some lube as the gears appear dried out.
As well known, on this 81 trail bike Honda omitted lots of the chromed parts from this model year and just painted em black, to save dough no doubt.
Some parts are still chromed on this 81, like the blinker stays front and rear.
ps...Now that you mention it, it does look like it could use some lube as the gears appear dried out.
Last edited:
cjpayne
Well-Known Member
Glad I was wrong.LOL
It is possible to go through an `81. The lack of chrome makes life easier. A scarred outer housing can be revived beautifully and on the cheap with normal body & paint work. On the other side of the equation, the lack of spare parts (i.e. donor speedometers) means you're essentially "working without a net". Unlike K0, which are comparatively plentiful and are virtually 100% parts-interchangeable, K1/HK1 which are a distant second place in that regard and the K2-`79s which are much harder to find and have even fewer viable parts interchanges possible, the `80s units are orphaned by yet another order of magnitude.
Complicating matters even further is the temperamental & fragile odometer/drive assembly. Getting the odometer stack apart, then properly reset & reassembled is far trickier than with the early models, especially K0.
I've gone through fewer than a half-dozen `80-`84s and the last one was a few years ago. They just aren't very common, or in demand. Otherwise, I could give you precise details without a refresher. The last one was mangled when the guy's bike was stolen. The housing was dented, the bottom of the drive cage looked like it was frowning and the needle was jammed. After a half day worth of slow, painstaking, work, it was working properly and looking like NOS. Happily, the original glass was perfect, right down to the break-in warning decal and the dial completely fade-free...talk about the Karmic door swinging in both directions! :4: Had it been a K0-K1, I'd have just sourced another unit.
Just FYI...the original black paint was low-gloss, not flat. A small but key difference. Flat black isn't as durable over the long haul.
Complicating matters even further is the temperamental & fragile odometer/drive assembly. Getting the odometer stack apart, then properly reset & reassembled is far trickier than with the early models, especially K0.
I've gone through fewer than a half-dozen `80-`84s and the last one was a few years ago. They just aren't very common, or in demand. Otherwise, I could give you precise details without a refresher. The last one was mangled when the guy's bike was stolen. The housing was dented, the bottom of the drive cage looked like it was frowning and the needle was jammed. After a half day worth of slow, painstaking, work, it was working properly and looking like NOS. Happily, the original glass was perfect, right down to the break-in warning decal and the dial completely fade-free...talk about the Karmic door swinging in both directions! :4: Had it been a K0-K1, I'd have just sourced another unit.
Just FYI...the original black paint was low-gloss, not flat. A small but key difference. Flat black isn't as durable over the long haul.
Adam-NLV
Well-Known Member
Mad Proper respect to racerX for finishing up my 81' Speedometer!!:77:
As you can see, he went through the unit, repaired a dent on the side (that I wasn't even aware of)! He didn't bondo it but braised it with metal filler. Plain Awesome work.
Also removed a dent from the trim ring repaired the gasket, repainted the unit, resealed it and oh yeah.... rolled back the mileage to zero, which is no easy task.
The only thing he didn't do is bake it in the Vegas sun @ 99F for 5 hours, which I gladly am taking care of right now (rotating it every 30 min). This will make the paint baked-on and almost impervious to scratching.
My hats off Bob, you the man.:usa2:
ps. Any imperfections in the pictures you see, were caused by me and my rookie missteps.
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As you can see, he went through the unit, repaired a dent on the side (that I wasn't even aware of)! He didn't bondo it but braised it with metal filler. Plain Awesome work.
Also removed a dent from the trim ring repaired the gasket, repainted the unit, resealed it and oh yeah.... rolled back the mileage to zero, which is no easy task.
The only thing he didn't do is bake it in the Vegas sun @ 99F for 5 hours, which I gladly am taking care of right now (rotating it every 30 min). This will make the paint baked-on and almost impervious to scratching.
My hats off Bob, you the man.:usa2:
ps. Any imperfections in the pictures you see, were caused by me and my rookie missteps.
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rip68
Member
Ok, Aside from the possibility of me doing some damage to my speedo similar to this one. I realized that the stock speedo is a 6v & I'm converting over to a 12v system. Has anyone tried the Koso DL Universal Electronic Speedometer?
DL UNIVERSAL ELECTRONIC SPEEDOMETER
DL UNIVERSAL ELECTRONIC SPEEDOMETER
The original speedometers are mechanical. All it takes to "convert" one to 12v operation is bulb replacement.
rip68
Member
They make those teenie bulbs in 12v? Ok, even if they do, I don't exactly have surgeons hands to operate on my speedo to get the thing apart so that I could send the housing off to be chromed. I'm thinking of just saving my self a headache & going with this digital one. Anyone ever used these?
12v bulbs aren't even hard to find. With a little creativity, it's also possible to retrofit LEDs into the original bulb sockets...done once, virtually for good, and outwardly stock-appearing. That said, however, it seems there's more behind your decision than you've posted. Not trying to steer, or second-guess, anyone...only provide information that will allow you to make a fully-informed decision. What is(are) your goal(s)?
The short answer to your question is that while I've not tested that particular unit and, as yet, have no knowledge of its longterm viability, I don't see any reason why it would not work with a 12v electrical system. While KOSO has multiple product lines, they've come on strong over the last 5 years, or so, and are more than capable of turning out quality product...some of which is re-branded and sold at a big premium.
If your stock speedo has a chromed housing, then I have to assume it's a round unit from a K1-`79 model. You are right, successfully restoring these...especially if the chrome needs to be redone...is one of the most challenging of projects. The teardown & reassembly are far more difficult than with a K0; replicating the matte chrome finish is a fiendishly tricky process. Still, it can be done.
rip68
Member
Yes it is a round unit 72' K1. I don't particularly have faith in my ability to take it apart without damaging the unit. I have large hands with sausages for fingers. As a matter of fact it is hard for me to type this out without hitting other keys in the process, so I will keep this short. Lol. I am modifying the bike anyways (modern alloy swingarm, decals & such) so it is not going to be a stock bike. Hence the curiosity for an easier option for a speedo. Thank you for your informative reply racerx. Take Care, Ed
You can't really go wrong when you have clear goals and recognize where your skill set has a gap.
An aftermarket speedometer is, like most mods, little more than a glorified bolt-in item, easily swapped-in and changed back...when & as you like. Mothball your original speedo and you'll always have the option to resintall/restore it later. At the very least, unmolested, it's an appreciating asset.
If you happen to like that particular KOSO unit, go for it. The bottom line will be close to the cost of restoring a K1 speedo with bad chrome, taking dollars out of the equation. There are a lot electronic gauges on the market and the number is growing, while prices are becoming more reasonable. If you're looking for something at the lower cost end you might take a look through the Trail Tech catalog. KOSO makes a number of other gauges, ranging widely in price points. At the higher end of the spectrum, Acewell, Dakota Digital, Motogadget, Stewart-Warner and Autometer all offer electronic speedometers. It boils down to personal taste and budget.
An aftermarket speedometer is, like most mods, little more than a glorified bolt-in item, easily swapped-in and changed back...when & as you like. Mothball your original speedo and you'll always have the option to resintall/restore it later. At the very least, unmolested, it's an appreciating asset.
If you happen to like that particular KOSO unit, go for it. The bottom line will be close to the cost of restoring a K1 speedo with bad chrome, taking dollars out of the equation. There are a lot electronic gauges on the market and the number is growing, while prices are becoming more reasonable. If you're looking for something at the lower cost end you might take a look through the Trail Tech catalog. KOSO makes a number of other gauges, ranging widely in price points. At the higher end of the spectrum, Acewell, Dakota Digital, Motogadget, Stewart-Warner and Autometer all offer electronic speedometers. It boils down to personal taste and budget.
RustySkills
Active Member
This is a great write-up! Does anyone know where to get the rubber cover ring for a round spedo housing? K1 is specifically what I need but it looks like they were the same for a long time.
red69
Well-Known Member
Thanks to bc17a, I was able to see how the speedo could be disassembled. Thanks for the pictures.
I didn't have to disassemble the odometer wheel because it's in fairly good shape. I was able to remove the retaining clip, but I didn't want to force the wheels in order to reset the reading. I chickened out and presently have my drill doing the reverse hula.
One funny thing that happened was when I pried off the pointer and I wasn't ready for it to shoot up and land somewhere amongst my RC planes. Luckily, I was able to locate it without much trouble. I had to make a new red light indicator by hand from clear plastic, since I do not have a lathe. I painted the rear using red epoxy paint. The rubber boot inside the housing on the bulb tube was shot but there was another one inside on a tube that is not used and it was swapped to the tube in use.
I haven't reassembled it yet as I am waiting for the odometer to zero out. One of the pictures shows the new overlay with the bezel and glass on top.
I didn't have to disassemble the odometer wheel because it's in fairly good shape. I was able to remove the retaining clip, but I didn't want to force the wheels in order to reset the reading. I chickened out and presently have my drill doing the reverse hula.
One funny thing that happened was when I pried off the pointer and I wasn't ready for it to shoot up and land somewhere amongst my RC planes. Luckily, I was able to locate it without much trouble. I had to make a new red light indicator by hand from clear plastic, since I do not have a lathe. I painted the rear using red epoxy paint. The rubber boot inside the housing on the bulb tube was shot but there was another one inside on a tube that is not used and it was swapped to the tube in use.
I haven't reassembled it yet as I am waiting for the odometer to zero out. One of the pictures shows the new overlay with the bezel and glass on top.