Author Topic: Contact breaker points  (Read 8647 times)

Offline Bryanj

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Re: Contact breaker points
« Reply #30 on: August 05, 2026, 04:33:00 PM »
Never seen a worn advancer cam, seen rusty ones.

When fitting new contacts they need rechecking at about 1000 to 1500 as the fiber heel will wear slightly to fit cam profile BUT if you get them set right first all you will have to do is open the gap a fraction  to get timing correct.

From memory the Honda book specifies 0.35mm or 14 thou with i think 12 to 16 being allowable, i always found that if you took the time and had the patience  0.35mm and firing spot on the F got you a sweet running motor, it takes practice and time because when you rotate the plate(s) the gap alters and resetting the gap alters the timing.

I have rarely used a dwell meter and proved to and apprentice many years ago that the correct use of feeler gauges was just as accurate.

As to getting points, it was cheaper to buy the complete plate if you neede condensers as well but it was over £120, dont know now or even if its available, i have one left for my bike.
Aftermarket condensers are a real crapshoot, some are bad straight out of the box.

Offline Oddjob

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Re: Contact breaker points
« Reply #31 on: August 06, 2026, 12:29:01 AM »
I have a shed load of new TEC condensers if you ever need any Bryan. The points plates seem to have dried up now, some Daichi ones still around though, check before you buy, if you see the 3 propellers avoid.
Kids in a the back seat cause accidents.
Accidents in the back seat cause kids.

Offline Ken4004

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Re: Contact breaker points
« Reply #32 on: August 06, 2026, 10:56:02 AM »
Good experiment. Might be an answer for other members as well. DS still has around 24 sets of 1-4s but no 2-3s. If it works it may just be an answer until he runs out of original points that is.
Be sure to let us know, could be very interesting.

Good morning everyone, well that didn’t go well !

I have just done the experiment fitting the Tec points (1-4) to a new base plate  and it was miles out and no way of getting to time without a-lot of filing so I think as an experiment it was worth trying but a total failure as parts are a not so mismatch.
The other thing I just noticed is that the new points I bought had the three propellers so not surprised I was having a problem but you live and learn.


So fitting back the new points and going to have to live with a slight misalignment on 2-3 points.

I still have the original tec points assembly so might clean up both sets of point faces and fit the original points assembly back on the bike and see how that goes so a job for the weekend.
« Last Edit: August 06, 2026, 11:06:19 AM by Ken4004 »

Offline McCabe-Thiele (Ted)

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Re: Contact breaker points
« Reply #33 on: August 06, 2026, 12:08:00 PM »
I bought a base plate from Steve at 400 parts that had as new Tec points fitted at sensible money.
Honda CB400NA Superdream (current money puddle)
Honda CB500 K1 (second money pit)
https://www.sohc.co.uk/index.php/topic,28541.0.html
Honda CB400 four super sport (first money pit)
Link to my full restoration http://www.sohc.co.uk/index.php/topic,23291.0.html
This is a neat 500 restoration in the USA.
http://forums.sohc4.net/index.php/topic,151576.msg1731556.html#msg1731556

Offline Oddjob

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Re: Contact breaker points
« Reply #34 on: August 06, 2026, 12:13:59 PM »
Has he still got some though Ted. I haven’t seen them for ages now, even in America.

Worth a go though Ken, kudos for trying. I may buy a set of Daichi points and dismantle them to compare with the TEC ones. Measure the heel etc. I do know that the pivot point bushing is inferior, think TEC has a bronze bush and Daichi may have a nylon one, something like that, read it once somewhere. Try gapping at 12 years though on both pairs and see if that helps.

As advised, if cleaning the contact faces dismantle the points so you can keep the faces flat.
Kids in a the back seat cause accidents.
Accidents in the back seat cause kids.

Offline McCabe-Thiele (Ted)

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Re: Contact breaker points
« Reply #35 on: August 06, 2026, 12:19:22 PM »
I'm going back a couple of years, it was a very good  used plate.
Honda CB400NA Superdream (current money puddle)
Honda CB500 K1 (second money pit)
https://www.sohc.co.uk/index.php/topic,28541.0.html
Honda CB400 four super sport (first money pit)
Link to my full restoration http://www.sohc.co.uk/index.php/topic,23291.0.html
This is a neat 500 restoration in the USA.
http://forums.sohc4.net/index.php/topic,151576.msg1731556.html#msg1731556

Offline florence

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Re: Contact breaker points
« Reply #36 on: August 06, 2026, 12:45:20 PM »
Good experiment. Might be an answer for other members as well. DS still has around 24 sets of 1-4s but no 2-3s. If it works it may just be an answer until he runs out of original points that is.
Be sure to let us know, could be very interesting.

Good morning everyone, well that didn’t go well !

I have just done the experiment fitting the Tec points (1-4) to a new base plate  and it was miles out and no way of getting to time without a-lot of filing so I think as an experiment it was worth trying but a total failure as parts are a not so mismatch.
The other thing I just noticed is that the new points I bought had the three propellers so not surprised I was having a problem but you live and learn.


So fitting back the new points and going to have to live with a slight misalignment on 2-3 points.

I still have the original tec points assembly so might clean up both sets of point faces and fit the original points assembly back on the bike and see how that goes so a job for the weekend.

I'm even more confused now.  Are there different base plates?  Mine has the original one.


Offline McCabe-Thiele (Ted)

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Re: Contact breaker points
« Reply #37 on: August 06, 2026, 12:56:52 PM »
I believe there were two suppliers originally, for advancer & back plate.
TEC was one.
Honda CB400NA Superdream (current money puddle)
Honda CB500 K1 (second money pit)
https://www.sohc.co.uk/index.php/topic,28541.0.html
Honda CB400 four super sport (first money pit)
Link to my full restoration http://www.sohc.co.uk/index.php/topic,23291.0.html
This is a neat 500 restoration in the USA.
http://forums.sohc4.net/index.php/topic,151576.msg1731556.html#msg1731556

Offline Bryanj

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Re: Contact breaker points
« Reply #38 on: August 06, 2026, 02:33:22 PM »
Daichi used to sell a complete plate as well back in the 70's, but they were decent parts then

Offline deltarider

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Re: Contact breaker points
« Reply #39 on: August 06, 2026, 02:39:27 PM »
Daichi used to sell a complete plate as well back in the 70's, but they were decent parts then
Also to my knowledge. Dunno what has happened afterwards.
BTW, is this about a CB400F? Then better consult the partlists or CMSNL. I'm still not sure if it was one size fits all. Didn't the CB350F/400F have -333- in the middle of the partsnumbers concerned?

Offline florence

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Re: Contact breaker points
« Reply #40 on: August 06, 2026, 02:44:41 PM »
no, this is about 500/550

Offline taysidedragon

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Re: Contact breaker points
« Reply #41 on: August 07, 2026, 12:49:01 AM »
I believe there were two suppliers originally, for advancer & back plate.
TEC was one.

Did Nippon Denso ND make the other one?
Gareth

1977 CB400F
1965 T100SS

Offline McCabe-Thiele (Ted)

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Re: Contact breaker points
« Reply #42 on: August 07, 2026, 07:40:53 AM »
I believe there were two suppliers originally, for advancer & back plate.
TEC was one.

Did Nippon Denso ND make the other one?

Thats the one, I could not remeber the name yesterday, ;D
Honda CB400NA Superdream (current money puddle)
Honda CB500 K1 (second money pit)
https://www.sohc.co.uk/index.php/topic,28541.0.html
Honda CB400 four super sport (first money pit)
Link to my full restoration http://www.sohc.co.uk/index.php/topic,23291.0.html
This is a neat 500 restoration in the USA.
http://forums.sohc4.net/index.php/topic,151576.msg1731556.html#msg1731556