Digital speedometer RPM install

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Hamman
Posts: 23
Joined: Fri Jul 21, 2017 10:49 am

Digital speedometer RPM install

Postby Hamman » Fri Nov 15, 2019 8:04 pm

Hey all, been some time! I recently picked up another 1981 CB! I am installing a new digital speedometer. The RPM/Tacho section states to "Connect RPM wire to one of the trigger wires positive pole."

Do you think If I ran the RPM signal wire from the speedo down to the pulse area and attach it to one of the small phillips mounting bolts that it would pick up a signal to read back to the Tacho?

There is no way clearly to get it onto a mounting point unless part of the wiring was sheathed back and the RPM wire was soldered onto it...

I suppose I could splice it into the harness either Yellow or Blue wires but wanted to gauge some thoughts. I think directly at the coils may be too much voltage and could potentially damaged the tacho.

Thanks!

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GeorgeSweety
Posts: 418
Joined: Tue Aug 08, 2017 11:47 am
Location: UK.

Re: Digital speedometer RPM install

Postby GeorgeSweety » Sat Nov 16, 2019 3:27 pm

Hi Hamman, have a look at this, its a conversion on an 81 Suzuki but its all I could find for now. Hope it is some help or good for ideas. Regards, George.

https://www.youtube.com/watch?v=u_xmU0d1T0o

Hamman
Posts: 23
Joined: Fri Jul 21, 2017 10:49 am

Re: Digital speedometer RPM install

Postby Hamman » Wed Nov 20, 2019 11:15 am

Thanks mate, I figured it out. The speedo has two settings for single cylinders and multi (2-4) cylinders. I was able to tap into the yellow (+) coil wire and it works great. Thanks!

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GeorgeSweety
Posts: 418
Joined: Tue Aug 08, 2017 11:47 am
Location: UK.

Re: Digital speedometer RPM install

Postby GeorgeSweety » Wed Nov 20, 2019 11:21 am

Hamman wrote:Thanks mate, I figured it out. The speedo has two settings for single cylinders and multi (2-4) cylinders. I was able to tap into the yellow (+) coil wire and it works great. Thanks!

Nice one Hamman, glad you sorted it :D

Hamman
Posts: 23
Joined: Fri Jul 21, 2017 10:49 am

Re: Digital speedometer RPM install

Postby Hamman » Mon Nov 25, 2019 10:57 am

Thanks, yes it works great! Nice having something updated. Now to find some 82 carbs :)

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GeorgeSweety
Posts: 418
Joined: Tue Aug 08, 2017 11:47 am
Location: UK.

Re: Digital speedometer RPM install

Postby GeorgeSweety » Mon Nov 25, 2019 11:09 am

Hamman wrote:Thanks, yes it works great! Nice having something updated. Now to find some 82 carbs :)

Why do you need 82 carbs? weren't there any with the bike when you got it?

Hamman
Posts: 23
Joined: Fri Jul 21, 2017 10:49 am

Re: Digital speedometer RPM install

Postby Hamman » Tue Nov 26, 2019 12:07 pm

GeorgeSweety wrote:
Hamman wrote:Thanks, yes it works great! Nice having something updated. Now to find some 82 carbs :)

Why do you need 82 carbs? weren't there any with the bike when you got it?


No it has carbs with it, VB44A's. The bike came with a 4-1 exhaust and pods. Previous owner dyno jetted it I believe. Has adjustable needles and 120's but has the pressed in pilots. I was able to get them out yesterday after a few hours :x Still had the stock 35's pressed in. The bike was extremely difficult to start when cold but once warm fires up immediately. Mids to WOT runs great! So, fresh intake boots, adjusted valves and an order of 40 pilot jets and we should be back in business.

I was thinking about just grabbing a used rack of 82 carbs but for the price and how well the bike does run with these carbs once warm I am guessing that the stock pilots just needed to go. Cheers!


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