Single cylinder tachometer

[carofmadness]

Hi all, looking for some advice regarding a tachometer for a single cylinder bike. the bike does not have a mechanical tachometer drive and did not come with one from the factory.

The bike uses a points ignition system with wasted spark

I currently have a 60mm chrome speedo fitted to my bike and would like a tachometer to match as I like the look of 2 clocks on a cafe racer. While browsing the internet I came across a tachometer that matches my speedo and it was a good price, it said it is universal and works with most bikes so I purchased it. this is the same as the one that I ordered:

https://www.ebay.co.uk/itm/Warrior-Mini-60mm-Chrome-Tacho-Motorcycle-Bike-0-15-x-1000-RPM-Electronic/302333027399

When it arrived I looked at the installation instructions and it says that it is for 2 cylinder bikes so I don't believe it will work on my bike.

so my question is will it work or give me an incorrect reading? I don't want to fit it if it will read incorrectly because I would not be able to return it if it has been removed from the package.

If it will read incorrectly can I get an adapter to make it work?
something like this . . .? https://www.ebay.co.uk/itm/UNIVERSAL-TACH-ADAPTER-CONVERTER-COP-1-2-3-4-5-6-8-10-cyl-to-any-4-6-8-Tach/141979625888

I don't really want to purchase the above item as I am in the UK and shipping from America could bring customs charges. So does anyone know of something similar that I could use to convert the signal from the coil to what the tachometer will need to read correctly?

I did find an old post on the forum explaining a lot of this but it was for a car tachometer and just want somebody with a better understanding to tell me if it will work or not and to guide me in the right direction to get an adapter to make it work if one is needed. Here is the link to the forum post

https://www.bikechatforums.com/viewtopic.php?t=223779

Thanks in advance
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2018 Black Royal Enfield Continental GT 535 Single Cylinder (daily) : 1985 Honda CG125 (my first bike) : 2014 AJS Daytona 125 (my mums bike)

[Riejufixing]

Phone up Demon Tweeks and ask them, they have the same product.....

[jeffyjeff]

It is unlikely that anyone on this forum will be able to give you a definitive answer. However, you say you have points ignition with wasted spark (spark plug fires at TDC compression and TDC exhaust strokes). That would replicate a twin cylinder engine without a wasted spark and a 360 degrees between firing impulses.

The disclaimer in your installation instructions notwithstanding, I will venture an educated guess that it will probably work. If it does not, you might be able to find and adapter that will work with it. OR, there may be some dip switches inside the casing that will allow it to work in your installation.

Bottom line, you have taken a calculated risk in purchasing this tachometer, and you will not likely find a guarantee that it will work on your motor on this forum. If you're unwilling to take a chance, then I agree with Riejufixing...pick up the phone.
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History shows again and again how nature points out the folly of men - BOC

[WD Forte]

What sodding bike?
is it secret?
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bikers smell of wee

[steve the grease]

It should work.
A single with a wasted spark and a 360^ twin with wasted spark would have an identical ignition system, ie it sparks once every revolution.
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All the above is my personal opinion, you can see my lips move, but I'm talking out of my arse.
I've been riding, and fixing , bikes for 50 years, in that time the more I learn, the less I am absolutely sure of.....

[The Shaggy D.A.]

[carofmadness]

Yeah it is an 85 CG, I know it won't use the full range of the tachometer but it won't use the 160mph Speedo either. All my friends ask why I still want to ride it when I have a full licence and the answer it because it's fun and a laugh hence the stupid Speedo and tachometer. The whole point of the bike is to be loud and make people think why would someone do that to a basic little bike.
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2018 Black Royal Enfield Continental GT 535 Single Cylinder (daily) : 1985 Honda CG125 (my first bike) : 2014 AJS Daytona 125 (my mums bike)

[WD Forte]

£40 tacho on an 85 CG eh?

Hmmm, that'd double the value of it I spose.
But, the extra weight would probably slow it down
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bikers smell of wee

[stinkwheel]

That tacho looks very like the £8 chinese one I fitted to my bullet.

The needle moved. Slowly and with no real degree of accuracy. Certainly coulodn't keep up with the motor, you'd have blown the engine and it would still have been climbing.

You don't really need one on a CG125 anyway. If you want the aesthetics of one, just but a cheap chinese unit and don't bother wiring it in, or prise the front off and fit a clock.
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[wr6133]

Don't waste your time use your ears, failing that when your teeth start to rattle, shift up, when the bike starts to chug shift down. If your fillings fall out or the bike stalls you left it too late.

[Pete.]

A tacho is one of those novelty devices that you hanker after if you don't have one but never actually look at after the first few times.

Their most useful feature is that you can check which gear the rpm is a direct multiple of the road speed and use it to tell your speed should your speedo ever pack up.
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a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[carofmadness]

All of my other bikes have a tachometer and as I said I like the look of 2 clocks on a bike rather than just one. I know I don't need one but I want it for the look more than anything else.
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2018 Black Royal Enfield Continental GT 535 Single Cylinder (daily) : 1985 Honda CG125 (my first bike) : 2014 AJS Daytona 125 (my mums bike)

[The Shaggy D.A.]

I guess it doesn't matter if it works or not, then
____________________
Chances are quite high you are not in my Monkeysphere, and I don't care about you. Don't take it personally.
Currently : Royal Enfield 350 Meteor
Previously : CB100N > CB250RS > XJ900F > GT550 > GPZ750R/1000RX > AJS M16 > R100RT > Bullet 500 > CB500 > LS650P > Bullet Electra X & YBR125 > Bullet 350 "Superstar" & YBR125 Custom > Royal Enfield Classic 500 Despatch Limited Edition (28 of 200) & CB Two-Fifty Nighthawk > ER5

[The Shaggy D.A.]

Thinking about it, it'll probably either read half the revs, the revs, or twice the revs. Could always print up a custom dial that works for the gauge, rather than getting the needle to read correct.
____________________
Chances are quite high you are not in my Monkeysphere, and I don't care about you. Don't take it personally.
Currently : Royal Enfield 350 Meteor
Previously : CB100N > CB250RS > XJ900F > GT550 > GPZ750R/1000RX > AJS M16 > R100RT > Bullet 500 > CB500 > LS650P > Bullet Electra X & YBR125 > Bullet 350 "Superstar" & YBR125 Custom > Royal Enfield Classic 500 Despatch Limited Edition (28 of 200) & CB Two-Fifty Nighthawk > ER5

[WD Forte]

Just saw one on Ebay
Half the price at £19.99 and it goes up to 16!
The Warrior only goes up to 15
Gotta be better right?

Anyway
As you have it, why not just do a quick test set up using flying leads
for 12v, Ground and pulses on the LT lead?
If it reads half or double, send it back and demand refund
if it works OK bolt it on.
____________________
bikers smell of wee

[carofmadness]

Today I finally got some time in the garage to work on my bikes.

I set up some flying leads as suggested to get this tachometer working and it works perfectly with the old cg that I have put it on, I would highly recommend it to anyone that want a tachometer for a single, it was lovely and easy to install.

After verifying that it works I decided to install it properly and encountered so many issues with bodged wiring at, someone used black for all of the wires within the headlight so I cut it all out and replaced with the correct colours only to find that it wouldn't power on with the ignition.

after double checking all of the wiring i had just done I thought that I had better check the fuse and bam the fuse was blown, replaced the fuse and all works fine.

So all in all it took 10 mins to verify that it worked with the bike and then 3 hours to install properly because of the wiring and the fact the the wiring diagram in the workshop manual was in black and white hindered me quite a bit.

All that is left to do is make some spacers to drop them down a bit as it looks kinda goofy mounted where it as right now, just want it to sit level with the top yoke instead of the whole tachometer sitting above it.
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2018 Black Royal Enfield Continental GT 535 Single Cylinder (daily) : 1985 Honda CG125 (my first bike) : 2014 AJS Daytona 125 (my mums bike)