« previous next »
Pages: [1]   Go Down

Author Topic: 500/550 vs. 650 vs. 750 Tach ratio?  (Read 715 times)

0 Members and 1 Guest are viewing this topic.

Online jgger

  • Master
  • *****
  • Posts: 2,401
500/550 vs. 650 vs. 750 Tach ratio?
« on: May 18, 2019, 08:23:00 AM »
This question pops into my pin head from time to time. Which bike matches the tach ratio (interchangeable) with the 650. I see tachs for sale for 500/550 & 750 all the time and I know they aren't interchangeable. So where does the red headed step child 650 land?

I bought my 79 650 moons ago and I'm slooooooooooooly gathering parts and would like to pick up a clean tach and speedo if I find the "deal of a lifetime". I'm sure others have asked or wondered about this,  I just can't remember ever seeing a definitive answer.

I hope I'm not starting an oil type thread🙈🙉🙊 any info would be helpful. T.I.A.

Jim
Logged
"The SOHC4 uses a computer located about 2-3 ft above the seat.  Those sometimes need additional programming." -stolen from  Two Tired

The difference between an ass kisser and brown noser is merely depth perception.  Stolen from RAFster122s

Offline Shtonecb500

  • Master
  • *****
  • Posts: 1,681
    • Youtube profile
Re: 500/550 vs. 650 vs. 750 Tach ratio?
« Reply #1 on: May 18, 2019, 08:31:01 AM »
found on cognito moto gauges page.

Logged
73/74'' CB500/550 resto-mod - sold
75' 750f 91' cbr f2 swap cafe - mock up
74' 750 chopper hardtail - complete - sold
74' CB750/836kit - Black mix & match - daily rider - always tweaking
71' cb500 K0 survivor - complete
71' K1 - CANDY GOLD/BROWN Winton kit - in process

Online jgger

  • Master
  • *****
  • Posts: 2,401
Re: 500/550 vs. 650 vs. 750 Tach ratio?
« Reply #2 on: May 18, 2019, 08:47:45 AM »
Thanks,now I can sleep tonight!🤪
Logged
"The SOHC4 uses a computer located about 2-3 ft above the seat.  Those sometimes need additional programming." -stolen from  Two Tired

The difference between an ass kisser and brown noser is merely depth perception.  Stolen from RAFster122s

Offline Gurp

  • I'm no.......
  • Master
  • *****
  • Posts: 2,171
  • Once was a...
Re: 500/550 vs. 650 vs. 750 Tach ratio?
« Reply #3 on: May 18, 2019, 09:26:39 AM »
Saved that in a hurry.
Logged
slow Progress 74 cb550.

Poor boy chop 73 CB500 chop


Future project 77 Cb750 Amen Savior/80 shovelhead chopper

"Alley Cat"  93 sportster

Online jgger

  • Master
  • *****
  • Posts: 2,401
Re: 500/550 vs. 650 vs. 750 Tach ratio?
« Reply #4 on: May 18, 2019, 09:42:43 AM »
Me too, I didn't think I was the only person that  wondered about that!
Logged
"The SOHC4 uses a computer located about 2-3 ft above the seat.  Those sometimes need additional programming." -stolen from  Two Tired

The difference between an ass kisser and brown noser is merely depth perception.  Stolen from RAFster122s

Offline david 750f

  • Expert
  • ****
  • Posts: 827
  • 1976 CB750F
Re: 500/550 vs. 650 vs. 750 Tach ratio?
« Reply #5 on: May 19, 2019, 11:57:18 AM »
Those 7:1 ratios are incorrect. Should be 20:3.

From the FAQ's.

CB750 Speedo  2240:60  Tach 4:1
CB650 Speedo  2240:60  Tach 4:1
CB550 Speedo  2240:60  Tach 20:3
CB500 Speedo  2240:60  Tach 20:3
CB400 Speedo  2240:60  Tach 20:3
CB350 Speedo  2240:60  Tach 20:3
Logged
1976 CB 750F

Online jgger

  • Master
  • *****
  • Posts: 2,401
Re: 500/550 vs. 650 vs. 750 Tach ratio?
« Reply #6 on: May 19, 2019, 01:50:01 PM »
I looked through the FAQ's and didn't find it. Is that on this site?

I might have to brush up on my hunting skills........or get a dog!
Logged
"The SOHC4 uses a computer located about 2-3 ft above the seat.  Those sometimes need additional programming." -stolen from  Two Tired

The difference between an ass kisser and brown noser is merely depth perception.  Stolen from RAFster122s
Pages: [1]   Go Up
« previous next »