Honda Twins banner

1 - 16 of 16 Posts

·
Registered
Joined
·
15 Posts
Discussion Starter #1
Hey,

I've bought a universal digital tachometer and am not sure where to connect the wire to get the RPMs.

Anything will help!

Thanks,

Michael
 

·
Premium Member
Joined
·
10,203 Posts
If you could supply a link to the instructions for the tach it could be helpful.
 

·
Premium Member
Joined
·
24,208 Posts
Typically the tach is looking for a coil connection of some sort, in this case with the CDI ignition the Yellow wire is used. The coil only get a pulse of power when it's fired.
 

·
Registered
Joined
·
459 Posts
is it one of those 5 wire tachs from ebay? With two red, two black and one yellow wire?

if so wiring is as follows
Yellow, tach signal
red (for back light) +12v switched
black (for back light) ground
red (for tach power) +12v switched
black (ground for tach) ground
 
  • Like
Reactions: Alan F.

·
Premium Member
Joined
·
5,610 Posts
On the Amazon site the wiring is described as such:

wiring instructions :
The tachometer Wire connection:


  • long Red light +
  • long Black light -
  • Short Black power/ignition lock +
  • Short Green Ground
  • Short Yellow engine signal line
The speedometer Wire connection:
  • long Red light +
  • long Black light -
 

·
Premium Member
Joined
·
24,208 Posts
  • long Red light + = Honda harness Brown w/White from the ignition switch
  • long Black light - = Honda harness Solid Green
  • Short Black power/ignition lock + = Honda harness solid Black from the ignition switch
  • Short Green Ground = Honda harness solid Green
  • Short Yellow engine signal line = Honda harness Yellow wire at the coil connector
 

·
Registered
Joined
·
15 Posts
Discussion Starter #13
Hello folks, I have tried all of the options above and in the videos and am unable to get an accurate rpm reading. With the universal gauge set for '2 cylinder' and wire connected to the yellow wire from cdi I'm getting approx double the rpm that I can hear (it's reading 4k but sounding like 2k). I've also tried setting the gauge for '4 cylinders' but then get an even higher inaccurate reading (reading 7.5k at the same 2k). I'm beginning to think the gauge is faulty. Are there any other possible connections you could suggest?

Thanks for your help,

Mike
 

·
Registered
Joined
·
459 Posts
Switch it to 1 cylinder. The SOHC 400/450 uses a waste spark system that fires both plugs one time per revolution.
 

·
Registered
Joined
·
234 Posts
I'm going to share my thoughts because I've spent many hours reading and searching.

Maybe your gauge is faulty or there's no settings for the waste spark system. If it's the one I think it is there are so many bad reviews. You'll find them on Amazon, Ebay, Wish, Aliexpress... they're all the same and you need luck to get a proper one. Somebody bought 3 of them and all were bad but I think it's mostly the speedometer. Some works good, some for a while and others doesn't work at all.
Before buying cheap products from China I always watch alot of videos, read comments and reviews and I don't trust good reviews were you can't update it since many ppl give good review right after they've got the product without testing them much or at all.

Anyway, do your own judgement.

Bad RPM:

If I lived in the USA I would probably get these (link below) but in mph. They come with different ratio, km/h or mph. You can find the same on Ebay that are extremely cheap but are they just as good?
Maybe, maybe not. I've read good reviews about the cheap ones but I'm a bit sceptical since the cheap ones in km/h only goes to 140 instead of 220 km/h. It means they're meant to be in mph which are 140 for this model.

https://www.dimecitycycles.com/2-5-...ini-kph-speedo-w-trip-tach-kit-1-4-ratio.html

You can also look for Acewell, Daytona or Koso. Even digital I guess since there is an analog to digital cable.
 
1 - 16 of 16 Posts
Top