Author Topic: Spark advancer shaft  (Read 191 times)

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Offline jwurbel

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Spark advancer shaft
« on: April 15, 2024, 10:40:01 am »
Had 200-400 rpm flutter on tach.  Used dial gauge per Hondaman and got down to maybe 100-150.  Don’t think I can get much better without replacement.   Should I just let it go and be happy or do the replacement?

Offline Don R

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Re: Spark advancer shaft
« Reply #1 on: April 15, 2024, 11:24:22 am »
 If you haven't yet, check the advancer springs to be sure the timing isn't fluttering there. My F1's weights were flopping around at idle.
No matter how many times you paint over a shadow, it's still there.
If you love it, set it free, if it stays it's probably one of my 750's.
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Offline jwurbel

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Re: Spark advancer shaft
« Reply #2 on: April 15, 2024, 11:28:27 am »
Did and they are not.  Good thought however

Online newday777

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Re: Spark advancer shaft
« Reply #3 on: April 15, 2024, 11:42:34 am »
You say you used a dial gauge per Hondaman.
Did you use a dial indicator like this and to what did you get it to? Less than .002"?
« Last Edit: April 15, 2024, 11:49:13 am by newday777 »
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 missed it greatly.....
1983 GL1100A, 1999 GL1500 SE, 1999 GL1500A

Online newday777

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Re: Spark advancer shaft
« Reply #4 on: April 15, 2024, 11:53:28 am »
From Hondaman's CB750 Book
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 missed it greatly.....
1983 GL1100A, 1999 GL1500 SE, 1999 GL1500A

Offline jwurbel

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Re: Spark advancer shaft
« Reply #5 on: April 15, 2024, 01:20:19 pm »
Like that and got the dial I thought to zero.  No movement on the dial pointer.  Measured more than once.  But it was my first time ever using one.  So it could have been off, but I don’t think so.

Online newday777

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Re: Spark advancer shaft
« Reply #6 on: April 15, 2024, 05:34:18 pm »
Like that and got the dial I thought to zero.  No movement on the dial pointer.  Measured more than once.  But it was my first time ever using one.  So it could have been off, but I don’t think so.
If you didn't start by pushing the indicator so it was at least. 020 and the turn the face to zero so there was pressure on the indicator to see if there was movement then you may need to redo it again if you have Flux idle.
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 missed it greatly.....
1983 GL1100A, 1999 GL1500 SE, 1999 GL1500A

Offline jwurbel

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Re: Spark advancer shaft
« Reply #7 on: April 16, 2024, 06:35:52 am »
I didn’t.  Kept it at zero, looking for any movement.  Probably will have it do again

Offline PeWe

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Re: Spark advancer shaft
« Reply #8 on: April 16, 2024, 06:41:02 am »
Zero or not, most important within the working range so it is not close to max or opposite pressed almost into bottom.

If needle does not move at all or only vibrate, very good ;D

This thread reminds me to measure my K2's shaft. It might wobble a little....
« Last Edit: April 16, 2024, 06:43:02 am by PeWe »
CB750 K6-76 1005cc JMR Billet block.
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Online newday777

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Re: Spark advancer shaft
« Reply #9 on: April 16, 2024, 06:52:18 am »
I didn’t.  Kept it at zero, looking for any movement.  Probably will have it do again
If you set it at zero at the high point you won't know how much it is off by to straighten it as the gauge won't reach out to the furthest point.
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 missed it greatly.....
1983 GL1100A, 1999 GL1500 SE, 1999 GL1500A

Offline PeWe

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Re: Spark advancer shaft
« Reply #10 on: April 16, 2024, 07:00:13 am »
If running Dyna-S or similar not that sensitive as points if shaft  wobbles.
CB750 K6-76 1005cc JMR Billet block.
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline jwurbel

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Re: Spark advancer shaft
« Reply #11 on: April 16, 2024, 10:51:06 am »
Actually using Hondaman’s transistor ignition module

Online newday777

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Re: Spark advancer shaft
« Reply #12 on: April 16, 2024, 11:31:34 am »
Actually using Hondaman’s transistor ignition module
👍
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 missed it greatly.....
1983 GL1100A, 1999 GL1500 SE, 1999 GL1500A