Ratio Rev Counter

[Pan47]

Hi,
now anybody what ratio the CB77 revcounter has?
Need this Information for my race CB 77.
Have try 2:1 3:1 and 5:1 nothing works.


Thanks Christian

[G-Man]

Hi Christian

When you say nothing works, what are you comparing with?

You can check the gearing revcounter drive in the head by watching how many engine rotations it takes to make one revolution of the cable.

G

[Tim Miller]

I have used CB92 race tachometers. The face reads 20:3 so, I suppose that would equally 6.666 :1 but I'm sure others will have something to say. Lol

Tim

Hi,
now anybody what ratio the CB77 revcounter has?
Need this Information for my race CB 77.
Have try 2:1 3:1 and 5:1 nothing works.


Thanks Christian

[DJM]

20:3 is the correct ratio for these bikes.

I believe that ratio was a Japanese Standard (JIS) for use on all bikes below 500cc.

I [think] that bikes over 500cc used a more usual 4:1 ratio.

[Pan47]

Thank you for Response

I buy the Smith replica revcounter from Scott Mitchell UK.
the first
4;1 was to slow real 6000 turns show me 2500-3000 turns

the second
2;1 was slower real 6000 turns show me 100-1500 turns

the last
7:1 ( Scott let build him for me ) show nothing

The cabel turns against clockwise. That was correct on my Smith revcounters.
I see also revcounter with Ratio 1:4 1:5 or 1:7 could this be the problem?

[Pan47]

The one i need is a revcounter for my racebike with Diameter 80 mm for mounting on the original CB 77 /72 cabel connector.

What have you guys on your racebike mounted?


(no electric )

[DJM]

Years ago I used a rev-counter off a small Kawasaki two stroke. It was the correct JIS ratio of 20:3 and worked fine. Can't remember the scale reading but it was on my race bike so must have been OK. It also came with an angled cable connection on the back which made mounting it and getting a good cable run much easier. It could have been off a KH250 or 350