« previous next »
Pages: [1]   Go Down

Author Topic: Throttle Spring Idea  (Read 763 times)

0 Members and 1 Guest are viewing this topic.

Offline Bigmant

  • Full Member
  • *
  • Posts: 90
Throttle Spring Idea
« on: January 24, 2023, 08:26:00 PM »
Hey gang!

I’m at the Mecum Auction this week, and noticed this gem on a CB750 cafe racer they are selling. I played with the throttle and noticed:
1. How easy it was to open the throttle
2. How positively and easily it returned to closed.

This of course prompted me to see how this was done, and the spring setup is what I found. Basically two springs hooked together, and then a string holding the rubber piece that prevents any rubbing. What are your guy’s thoughts? Anyone seen this before?
Logged
‘74 CB750 K4 Owned by my father and now me

Offline newday777

  • Really Old Timer ...
  • *******
  • Posts: 5,227
  • Avatar is my 76 K6 in Colorado w/Cody on back 1980
Re: Throttle Spring Idea
« Reply #1 on: January 25, 2023, 03:46:47 AM »
I haven't seen that before but might have to try it. Were the 2 springs hooked together under the rubber?
Logged
Stu
Honda Parts manager in the mid 1970s Nashua Honda
My current rides
1975 K5 Planet Blue my summer ride, it was a friend's bike I worked with at the Honda shop in 76, lots of fun to be on it again
1976 K6 Anteres Red rebuilding project, was originally my brother's that I set up from the crate, it'll breath again soon!
Project 750s, 2 K4, 2 K6, 1 K8
2008 GL1800 my daily ride and cross country runner

Prior bikes....
1972 Suzuki GT380 I had charge of it for a year in 1973 while my friend was deployed and learned to love street riding....
New CB450 K7 after my friend returned...
New CB750 K5 Planet Blue, demise by ex cousin in law at 9,000 miles...
New CB750 K6 Anteres Red, to replace the totaled K5, I sold this K6 at 45k in 1983, I had heavily modified it, many great memories on it and have missed it greatly.....
1983 GL1100A, 1999 GL1500 SE, 1999 GL1500A

Offline BenelliSEI

  • Really Old Timer ...
  • *******
  • Posts: 9,869
  • 1969 cb750
Re: Throttle Spring Idea
« Reply #2 on: January 25, 2023, 05:41:57 AM »
Looks like if the “string” breaks, no tension?
Logged

Offline ekpent

  • Really Old Timer ...
  • *******
  • Posts: 13,512
  • To many bikes-but lookin' for more
Re: Throttle Spring Idea
« Reply #3 on: January 25, 2023, 06:41:35 AM »
Maybe at least use some wire on that bodge.
Logged

Offline newday777

  • Really Old Timer ...
  • *******
  • Posts: 5,227
  • Avatar is my 76 K6 in Colorado w/Cody on back 1980
Re: Throttle Spring Idea
« Reply #4 on: January 25, 2023, 09:24:14 AM »
Quote from: ekpent on January 25, 2023, 06:41:35 AM
Maybe at least use some wire on that bodge.
That was my thought also. Probably thin stranded stainless steel with a sleeve of heatshrink.
Logged
Stu
Honda Parts manager in the mid 1970s Nashua Honda
My current rides
1975 K5 Planet Blue my summer ride, it was a friend's bike I worked with at the Honda shop in 76, lots of fun to be on it again
1976 K6 Anteres Red rebuilding project, was originally my brother's that I set up from the crate, it'll breath again soon!
Project 750s, 2 K4, 2 K6, 1 K8
2008 GL1800 my daily ride and cross country runner

Prior bikes....
1972 Suzuki GT380 I had charge of it for a year in 1973 while my friend was deployed and learned to love street riding....
New CB450 K7 after my friend returned...
New CB750 K5 Planet Blue, demise by ex cousin in law at 9,000 miles...
New CB750 K6 Anteres Red, to replace the totaled K5, I sold this K6 at 45k in 1983, I had heavily modified it, many great memories on it and have missed it greatly.....
1983 GL1100A, 1999 GL1500 SE, 1999 GL1500A

Offline pekingduck

  • Enthusiast
  • **
  • Posts: 203
Re: Throttle Spring Idea
« Reply #5 on: January 25, 2023, 09:29:58 AM »
I'm going to guess that that's a pair of hardware store springs that are shiny, and the big one was too short to reach to the lower plate/hook, and the two of them hooked together were too long. 

As stated above, this is a bodge job. A light throttle can be achieved with a single lighter spring of the right size.

Or you can make it even lighter by replacing the string with another, lighter spring.  Or a rubber band. Makes me think what other marvels of engineering are on that bike.
Logged

Offline Deltarider

  • Really Old Timer ...
  • *******
  • Posts: 8,121
  • ... but some animals are more equal than others.
Re: Throttle Spring Idea
« Reply #6 on: January 25, 2023, 12:50:33 PM »
An even simpler solution on the UK site.
Logged
CB500K2-ED Excel black
"There is enough for everyone's need but not enough for anybody's greed."

Offline Bigmant

  • Full Member
  • *
  • Posts: 90
Re: Throttle Spring Idea
« Reply #7 on: January 25, 2023, 04:22:23 PM »
Like I said, regardless of why this spring is the way it is, the throttle FEELS like a modern throttle. It’s easy to open, and snaps easily and positively shut. I agree about what happens if that string snaps though.
Logged
‘74 CB750 K4 Owned by my father and now me

Offline BenelliSEI

  • Really Old Timer ...
  • *******
  • Posts: 9,869
  • 1969 cb750
Re: Throttle Spring Idea
« Reply #8 on: January 25, 2023, 04:34:56 PM »
Quote from: Deltarider on January 25, 2023, 12:50:33 PM
An even simpler solution on the UK site.

I’ve done that and it makes a surprisingly big difference!
Logged

Offline Bigmant

  • Full Member
  • *
  • Posts: 90
Re: Throttle Spring Idea
« Reply #9 on: January 25, 2023, 07:06:06 PM »
Quote from: Deltarider on January 25, 2023, 12:50:33 PM
An even simpler solution on the UK site.

Can you guys explain this? I’m not exactly sure what this ring is that I’m looking at.
Logged
‘74 CB750 K4 Owned by my father and now me

Offline robvangulik

  • Honda Fourever
  • Expert
  • ****
  • Posts: 1,418
Re: Throttle Spring Idea
« Reply #10 on: January 26, 2023, 03:47:58 AM »
Quote from: Bigmant on January 25, 2023, 07:06:06 PM
Quote from: Deltarider on January 25, 2023, 12:50:33 PM
An even simpler solution on the UK site.

Can you guys explain this? I’m not exactly sure what this ring is that I’m looking at.
Just a simple washer.
Logged

Offline RAFster122s

  • I feel like a really really
  • Really Old Timer ...
  • *******
  • Posts: 12,325
  • SOHC4 member # 2605
Re: Throttle Spring Idea
« Reply #11 on: January 26, 2023, 10:21:44 AM »
It is an add on to the existing setup, so if it breaks you should be back to stock feel unless it jams something up...
Logged
David- back in the desert SW!
Pages: [1]   Go Up
« previous next »