Author Topic: Out of adjustment room for ignition timing (2-3)  (Read 1848 times)

0 Members and 3 Guests are viewing this topic.

Offline drumstyx

  • Hot Shot
  • ***
  • Posts: 729
Out of adjustment room for ignition timing (2-3)
« on: February 06, 2017, 04:40:44 pm »
I'm static timing the ignition on my rebuild and I've found I can't get the 2-3 point quite right...if I'm understanding it right, it'd fire a degree or two late. The 1-4 adjustment is also right at the end of its adjustment.

Am I missing something here? These points look in great condition, I gapped them down to 0.012 before and after adjusting the timing, and yet still it's just so close, but not quite.

The 1-4 timing is out of room clockwise, while the 2-3 timing is out of room counter clockwise, so I could turn the 1-4 (whole plate) slightly counter-clockwise and end up with something like 0.5 degrees off in either direction, but they'd still be a degree or so apart from eachother.

Offline Pat_at_APE

  • Enthusiast
  • **
  • Posts: 171
    • APE Race Parts
Re: Out of adjustment room for ignition timing (2-3)
« Reply #1 on: February 06, 2017, 04:46:58 pm »
You might have to open up the slots in the points a little.  I've had to do this before to get the timing right on the mark on a CB360. 

Regards,
Pat at APE

Offline 700504

  • Enthusiast
  • **
  • Posts: 201
Re: Out of adjustment room for ignition timing (2-3)
« Reply #2 on: February 06, 2017, 04:47:56 pm »
I had the same thing happen, shim the edges of the plate. I made a post about it here http://forums.sohc4.net/index.php/topic,152579.msg1743612.html#msg1743612
1978 cb750k
1977 cb750f2
1974 cb750k
1973 cb750k
1981 cb650 (rip)
1969 ct90

Offline drumstyx

  • Hot Shot
  • ***
  • Posts: 729
Re: Out of adjustment room for ignition timing (2-3)
« Reply #3 on: February 06, 2017, 05:14:26 pm »
Aright I think I got it...gaps make a HUGE difference in timing it seems.

These interdependent settings are infuriating. Electronic ignition is in my future.

Offline HondaMan

  • Someone took this pic of me before I became a
  • Really Old Timer ...
  • *******
  • Posts: 13,770
  • ...not my choice, I was nicknamed...
    • Getting 'em Back on the Road
Re: Out of adjustment room for ignition timing (2-3)
« Reply #4 on: February 06, 2017, 06:48:49 pm »
Electronic ignition is in my future.

Ah, then you might just be STARTING your adventure....

By chance: look closely at your points plate, see if it has a tiny 3-leafed-clover-like emblem on it? If so, it is Daiichi, which is the worst of the worst of points sets for these bikes. If you have the Honda TEC brand and are still suffering wide gaps in the mounting posts, take a close look to see if someone may have bent them outward before you? This happens, too. The TEC points may require some readjustment (i.e., bending) of the ground-side contact's support arm to make them meet the timing marks AND points gap. The gap should be 0.014", or at least not less than 0.012" least for both.
See SOHC4shop@gmail.com for info about the gadgets I make for these bikes.

The demons are repulsed when a man does good. Use that.
Blood is thicker than water, but motor oil is thicker yet...so, don't mess with my SOHC4, or I might have to hurt you.
Hondaman's creed: "Bikers are family. Treat them accordingly."

Link to Hondaman Ignition: http://forums.sohc4.net/index.php?topic=67543.0

Link to My CB750 Book: https://www.lulu.com/search?adult_audience_rating=00&page=1&pageSize=10&q=my+cb750+book

Link to website: www.SOHC4shop.com

DH

  • Guest
Re: Out of adjustment room for ignition timing (2-3)
« Reply #5 on: February 07, 2017, 05:42:40 am »
On occasion, when limits are reached, I tried with success, moving the points
plate up or down, (toward or away from the cam) if the points plate has enough
"slop" to do so. It's a little tricky to get gap AND timing both correct, but some times
things can be manipulated to proper ranges. Of course, it also depends on how
worn the points assemblies themselves are, and/or how loose the plate is inside the
mounting posts.

Offline drumstyx

  • Hot Shot
  • ***
  • Posts: 729
Re: Out of adjustment room for ignition timing (2-3)
« Reply #6 on: February 07, 2017, 06:56:30 am »
On occasion, when limits are reached, I tried with success, moving the points
plate up or down, (toward or away from the cam) if the points plate has enough
"slop" to do so. It's a little tricky to get gap AND timing both correct, but some times
things can be manipulated to proper ranges. Of course, it also depends on how
worn the points assemblies themselves are, and/or how loose the plate is inside the
mounting posts.

I can feel *maybe* a few thou of slop...feels like when rockers are properly adjusted, just a teeny wiggle...definitely feels very tight...but I didn't measure.

I didn't realize the gap made such a huge difference. I adjusted the gaps (lazily, if I'm honest) then made a huge adjustment to timing to time 1-4, then didn't check the gap again, which is probably what made 2-3 run out of adjustment so hard. I think I got it last night, then finished up the valve adjustment and closed 'er up. I'll double check tonight, and if I have the balls, it'll be the first run around 7pm! Bike is in the house, so I have to find some way of pointing the exhaust out the door.

Offline flybox1

  • My wife thinks I'm a
  • Really Old Timer ...
  • *******
  • Posts: 14,301
Re: Out of adjustment room for ignition timing (2-3)
« Reply #7 on: February 07, 2017, 07:06:07 am »
What brand points and points plate do you have?
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

Past Bikes
1974 550K0 (stock), 1973 CB350F (stock), 1983 Yamaha XS400K (POS)
77/78 cool 2 member #3
"Knowledge without mileage equals bullsh!t" - Henry Rollins

"This is my CB. There are many like it, but this one is mine…"

Offline drumstyx

  • Hot Shot
  • ***
  • Posts: 729
Re: Out of adjustment room for ignition timing (2-3)
« Reply #8 on: February 07, 2017, 07:24:30 am »
What brand points and points plate do you have?

This is the only pic I have right now from when I disassembled things a year ago, as I'm at work. Can you make out anything related to brand there?



EDIT: Hmm...just noticing now then, it looks like the 1-4 (full plate) timing is completely opposite to what I ended up with the other day. This bike was put away about 12 years ago, and supposedly ran...
« Last Edit: February 07, 2017, 07:27:59 am by drumstyx »

Offline flybox1

  • My wife thinks I'm a
  • Really Old Timer ...
  • *******
  • Posts: 14,301
Re: Out of adjustment room for ignition timing (2-3)
« Reply #9 on: February 07, 2017, 07:55:35 am »
Your points are Daiichi.  cant see any plate markings, but have to assume its daiichi as well.
Start with a new OEM ND or TEC points plate and points.
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

Past Bikes
1974 550K0 (stock), 1973 CB350F (stock), 1983 Yamaha XS400K (POS)
77/78 cool 2 member #3
"Knowledge without mileage equals bullsh!t" - Henry Rollins

"This is my CB. There are many like it, but this one is mine…"

Offline drumstyx

  • Hot Shot
  • ***
  • Posts: 729
Re: Out of adjustment room for ignition timing (2-3)
« Reply #10 on: February 07, 2017, 08:09:49 am »
Alright, I'll have a closer look when I get home.

I actually have a spare '78 I've been using for a parts bike, so I'll have a look at what points/plate are there too, and how they look.
Edit: Actually, am I crazy or do I make out a faint "TEC" just under and to the left of the top screw there?

So, assuming I have a TEC plate, I'd bet the points and condensers were replace with daiichi at some point... As far as I see, it's about $140CAD for a whole new plate including condensers, wires, points. It's about $100USD from partzilla, and all 4 components separately add up to about the same -- is there anywhere to buy the components cheaper? If not, I might as well just get the whole thing, and really at that point, I might as well spend the coin on an electronic ignition...
« Last Edit: February 07, 2017, 08:23:42 am by drumstyx »

Offline flybox1

  • My wife thinks I'm a
  • Really Old Timer ...
  • *******
  • Posts: 14,301
Re: Out of adjustment room for ignition timing (2-3)
« Reply #11 on: February 07, 2017, 08:20:39 am »
Might be, but IIRC the TEC logo is stamped closer to the center of the plate. 
If its a TEC plate, or you have another, first check to see how much lateral play there is between the plate and its mounting pillars.
if you can feel it slide around, you'll need a few shims from a beer or soda can to prevent this lateral movement.  THen proceed with setting the back plate in the middle of its rotational range before snugging it down.
Set the 1/4 points gap to .014"
Set use the 2/3 secondary plate and the 2/3 point itself to set the 2/3 point gap.
If you have a multimeter with a dwell function, set the point dwell now.
Then time it with a light.
Recheck dwell...
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

Past Bikes
1974 550K0 (stock), 1973 CB350F (stock), 1983 Yamaha XS400K (POS)
77/78 cool 2 member #3
"Knowledge without mileage equals bullsh!t" - Henry Rollins

"This is my CB. There are many like it, but this one is mine…"

Offline drumstyx

  • Hot Shot
  • ***
  • Posts: 729
Re: Out of adjustment room for ignition timing (2-3)
« Reply #12 on: February 07, 2017, 09:31:20 am »
If the daiichi logo is that flower looking thing, then my other bike has em too. Both have tec plates though. Is the dealer the only place to get Tec points and condensers?

Offline flybox1

  • My wife thinks I'm a
  • Really Old Timer ...
  • *******
  • Posts: 14,301
Re: Out of adjustment room for ignition timing (2-3)
« Reply #13 on: February 07, 2017, 09:44:08 am »
Yes, the flower log is Daiichi.  TEC can be bought on ebay....
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

Past Bikes
1974 550K0 (stock), 1973 CB350F (stock), 1983 Yamaha XS400K (POS)
77/78 cool 2 member #3
"Knowledge without mileage equals bullsh!t" - Henry Rollins

"This is my CB. There are many like it, but this one is mine…"

Offline drumstyx

  • Hot Shot
  • ***
  • Posts: 729
Re: Out of adjustment room for ignition timing (2-3)
« Reply #14 on: February 07, 2017, 09:52:30 am »
Yes, the flower log is Daiichi.  TEC can be bought on ebay....

Turns out it's only $100cad for a full replacement from the dealer. I think I'll just get that and upgrade with hondamans transistorized ignition in the summer.

Hopefully that solves my woes!

Offline PeWe

  • Really Old Timer ...
  • *******
  • Posts: 15,526
  • Bike almost back to the 70's 2015
Re: Out of adjustment room for ignition timing (2-3)
« Reply #15 on: February 07, 2017, 11:57:18 am »
I have also been there. Could not adjust to F when slots were not wide enough.
I fiddled around with the points gap and finally I could adjust. This was with a TEC plate. I remeber the same back in the days too, mostly Daichii plates.
I do not remember if I got more to adjust with Points at min gap.
Important to change point 1-4 which might be off. This will change the entire plate, startpoint for 2-3.
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
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