How to add a rmp meter on the Zongshen gy 200 and not only

[geo99rge]

After getting bored on Sunday morning i decide to transfer my rpm meter (universal) from the cub to the zongshen. The steps are as follows

1. this is the cub
http://img178.imageshack.us/i/p1010744m.jpg/

2. the rpm meter has 5 cable
a. blue and brown for the light
b. green and red the positive polarity
c. and finally the black the negative polarity

Here is a general photo http://img801.imageshack.us/i/p1010739b.jpg/

Step 1.
I needed to figure out a way when the motorcycle is shut-of it will not consume any electricity so I decide the best way was to connect 1 positive cable on the ignition key. Best thing to do, have with you a multimeter in order to find the correct cable polarity.
So after trying a couple of times I jam on the key fuse the green cable as seen in the below photo http://img714.imageshack.us/i/p1010740k.jpg/

Now the red had to be connected to the CDI on the top right cable as seen here (do not mind the color (brown) is an extension to the red} http://img201.imageshack.us/i/p1010745j.jpg/


The reason i put this way is if i did the other way around (green to cdi and red to keythe rpm meter gave me wrong readings

Step 2.
The black cable had to be inserted somewhere with negative polarity, so after some research i figure that the whole frame is polarized negative so I connect it to a screw! on the frame as seen here http://img214.imageshack.us/i/p1010743fp.jpg/

Step 3.
The easiest part was to find the light of the rpm meter so i connect it to the main light as seen here http://img213.imageshack.us/i/p1010741a.jpg/


This is a side photo of the rpm meter where it fits perfectly on top of the speedometer http://img219.imageshack.us/i/p1010747z.jpg/

This is the final result as seen here http://img513.imageshack.us/i/p1010748x.jpg/

After 3 days of driving the rpm meter was very accurate but after that there was a change increasingly to the indications +1000 rpm, we are going to figure where is the problem with a friend and keep you updated.

The rpm meter is universal and has a +-5% wrong reading hopefully we may find the problem but for a first attempt is promising. Also the transfer was made from the cub which is single cylinder, 12volt and about the same rpm as the zong.

All the best