Yes i did read it over and over again. I figured that i has to be on 4 sins i have 4 pistons and its a 4 stroke engine. You suggest to set it on 2?

 

In looking at the manual it looks like there are only 2 settings. Try the other one. It's a little confusing, because it says 1,2,3 and 4 cylinders...but there are only 2 settings. I'm not sure how the CBR coils fire...if they fire 2 cylinders at once and plugs fire even tho not both on compression stroke, then you would get the pulse for both cylinders to the tach...which would explain the RPM being half of total. You need to try the other setting which should double the output and give you the correct RPM. You can't hurt anything by trying it.

BTW, the 4 Stroke reference means nothing. I see that on a number of these gauges and it is just an incorrect reference. Makes no difference 2 stroke or 4 stroke. It's all based on an electrical pulse to the tach. I think the Chinese are confused

 

The f1 fires a wasted spark. But wouldn't that double the rpm rather than half it?

 

This is what I expected. The bike has two coils one for each bank of 2 cylinders. The tack is connected to one coil so only see's one signal...although it might be the same timing as the other coil...I'm not that well versed on CBR ignition. OP should still try other settings on the tach to see what happens since he's getting half the RPM.

 

Returned from the workshop and ges what. You where right. I set the tach one setting 2 and it works perfectly. I cant understand why i didn't think of it my self sins the bike has 2 coils . Thanks for all the help.

 

No problem glad you got it sorted