Topic: CB750 points plates Toyo, Hitachi, Nippon Denso, Futaba

[69cb750]

Toyo points plate
Most CB750's came with Toyo points plate (a few came with Hitachi)
Plate stamped Tec
Top slot longer then bottom slots

[69cb750]

Hitachi points plate
Some CB750's came with Hitachi plate
Plate and points have Hitachi emblem
All slots same size
Condensers have something like wax where wires come out

[69cb750]

Nippon Denso points plate
These plates were made after production ended
Plate and points have ND

[Stev-o]

Great info, thank you

[69cb750]

Futaba points plate
Toyo and Hitachi supplied original points plates, Futaba was an aftermarket supplier of points plates, made in Japan
Plate stamped "few"

[HondaMan]

I have about a dozen of the FEW marked condensors and points, but no plate with that mark.
I ordered one of the (NOS?) FEW points plate assemblies last week, will show it here when it arrives.

In my experience, the Hitachi points and condensors last the longest. Their points have curved contact faces while the others were largely flat.

[69cb750]

In my experience, the Hitachi points and condensors last the longest. Their points have curved contact faces while the others were largely flat.

I have brought ten bikes back to life with original points plate.
Most recent bike refused to start, tried two spare point plates, refused to start.
Had to use plate from running bike, quite the surprise, Japan condensers only last 55 years then they quit.

[scottly]

Let's include the various advance mechanisms..
On the left is a ND 333 from a 350/400, and on the right is a Tec 300, from a 750. On the 750, the F mark is 10* before the T mark, and the center of the two full advance marks is 35* before the T mark.

[Oddjob]

Correct me if I'm wrong but isn't the Futaba plate wearing Daichi points, the 3 pronged propellor mark is normally their mark is it not.

[69cb750]

Correct me if I'm wrong but isn't the Futaba plate wearing Daichi points, the 3 pronged propellor mark is normally their mark is it not.

Yes, Diachi junk.

[HondaMan]

In my experience, the Hitachi points and condensors last the longest. Their points have curved contact faces while the others were largely flat.

I have brought ten bikes back to life with original points plate.
Most recent bike refused to start, tried two spare point plates, refused to start.
Had to use plate from running bike, quite the surprise, Japan condensers only last 55 years then they quit.

The old condensors were made with paper and a waxy substance as their insulator (they called it a 'polymer', but I am dubious of that...). This insulation material dries out when it sits for a long time unused. To 'bring it back' often requires a usage of some sort: I usually apply an AC voltage to them (if they are not shorted from some failure) and leave it 'ON' for about 24-48 hours (some went weeks when I forgot about them). They were designed to redistribute the insulation after being parked for a long time (as many bikes are) with some use: this has typically been a good way to do it.

I have a couple of old model train transformers that supply 12vDC to a rheostat from a 16 volt AC transformer: both voltages are available on the unit. 'Tis a handy thing for this process.

[69cb750]

I have a couple of old model train transformers that supply 12vDC to a rheostat from a 16 volt AC transformer: both voltages are available on the unit. 'Tis a handy thing for this process.

How many have you revived ?
What is the success/failure rate ?
12v dc or 12v ac ?

[HondaMan]

I have a couple of old model train transformers that supply 12vDC to a rheostat from a 16 volt AC transformer: both voltages are available on the unit. 'Tis a handy thing for this process.

How many have you revived ?
What is the success/failure rate ?
12v dc or 12v ac ?

I 'saved' almost all of them, except some that had dents in their cases: they ended up having low-grade shorts in them.
In the little toy-train transformer I use, there is a 16vAC transformer and a rectifier (full wave) that wires up to the throttle knob for the DC output part. I use the AC output (provided for other train accessories, like lights and sounds, etc.) with a resistor

This all reminds me: I have to dig that gizmo out and 'wake up' some of the old Japanese Daiichi condensors I found last week in an old box: they are probably 20 years old and still brand new.

[CycleRanger]

Here's a crusty ND plate with ND points with those funky condensers that have the blobs of glue. I assume it's for a 350F based on the 333 marking?
I got this with several 750 plates from ebay years ago.

[jwurbel]

For what’s worth, I ordered a set that came up on EBay simply because the price, $48 plus free shipping, was so low.  The set is clearly stamped FEW.  Not sure of the state of the condensers.  Mark, how do you charge them? 

[eastern]

For what’s worth, I ordered a set that came up on EBay simply because the price, $48 plus free shipping, was so low.  The set is clearly stamped FEW.  Not sure of the state of the condensers.  Mark, how do you charge them?

I got one too.  Same.  All FEW markings. 

[jwurbel]

Just reread Mark’s earlier post.  Now I have to find my Lionel train…

[69cb750]

Ordered Futaba points plate.
Left points fiber to long, smallest gap .022" into the trash.
One condenser doa, probably worked 50 years ago.
Ordered four Toyo condensers from Yamiya.

[Oddjob]

Are you saying that these faults were on the new Futaba plate or your old plate? Not clear.

[HondaMan]

For what’s worth, I ordered a set that came up on EBay simply because the price, $48 plus free shipping, was so low.  The set is clearly stamped FEW.  Not sure of the state of the condensers.  Mark, how do you charge them? 

I connect the AC side of the transformer (usually it is around 16-20 volts) thru a 1k resistor to one lead and then clip another lead to the condensor case and let them sit that way for a few hours. But first, I always check (finger test!) to make sure they aren't just shorted, in which case they get warm (or the train transformer's little automatic circuit breaker starts clicking off-on). I have a couple dozen old Japan Daiichi condensors, one of which shorted during this test. They were made in the 1980s.

[69cb750]

Are you saying that these faults were on the new Futaba plate or your old plate? Not clear.

Futaba parts are low quality, Toyo and Hitachi parts are high quality.
Condensers have failed from all the above.
Any electronic part still working at 25 years is really good.