Hi from Germany!
Late, but maybe not too late..
I hadn't been here for quite awhile, that's why I'm not really up to date, but when I searched for some info about ignitors I found this thread.
I was searching for alternatives to my CDI systems for my Honda CX500Cs. Honda came up with that CDI type in the mid 1970s, using an unnecessarily complicate system/concept. The first CX500 came with 2 pickups for 10° including pickups for the limiting of the advancer to 37°plus/minus 3°, plus 2 pickups for the advancing itself. The CDI 'computed' the advance, using diodes. The stator of the generator had 2 high-voltage coils included, supporting the CDI with 85 to 105 volts.
These coils where mostly the reason for ignition probs, because after a mileage of 50 to 70 thousand Km, let's say 30 to 45 thousand miles, the protective coating was washed away by the hot oil and the ignitor no longer worked properly.
Quite often, the CDI was blamed for the malfunction in the first place, but mostly, it turned out to be the HV coils.
From 1982 on, Honda replaced that CDI system with a NEC ignitor, based on 12 to 14 volts from the battery instead the 85 to 105 volts from the generator, and the 4 (better: 6!) pickups were replaced by a conventional centrifugal force controller. That means: progress by regression ! ;-)
Bad for CX drivers: no more production from 1986 on... Getting problems today means to search for old spareparts - or new solutions!
Doing the latter, I tried to find a way to include my 'on-stock' material.
I still got one original TCI from the XS400 12E/16M, including ignition coils, and one set made by IgniTech.
Then I had to check out, whether the TCIs and the CDI might be able to replace each other and under what conditions.
Note: the ignition coils are slightly different and it is recommended to not only replace the CDI/TCI but also the ignition coils!
But YOU are XS drivers, not CX, so we have to look at the probs the other way round...
Going the a.m. way, I renewed my knowledge about the TCI.
As a good solution for real CDI malfunctions there appeared the IgniTech-CDI from Czechia, today coming only as a programmable CDI.
Anyway, it is a CDI, while the XS400 DOHC uses, as an original, a TCI instead.
However, IgniTech is still able to deliver such a TCI !
The IgniTech TCI may just replace the original Ignitor, as long as the pickups are working well.
The costs are somewhere inbetween 163 and 225 bucks, but you need to check the shipping costs carefully!
MY personal 'problems' were, that the CX500 needs 15° for idle, while the XS400 starts at 10°, and also the advancer for the CX500 goes up to 45° max, whereas the XS400 advancer goes up to 39° max (should..).
That's why I can't use that XS ignitor for the CX.
I need my XS ignitors for my 12E and my 16M anyway ;-)
But there are more solutions than the original spareparts or all above mentioned anyway.
Depends on your political way of thinking ;-)
Take a look at ALIEXPRESS ...
There you find solutions from 37 bucks upwards !
All you need, is to check out which more modern bike uses the most similar, if not identical ignition timing !
Maybe you check out aliexpress for a XS400DOHC ignitor, but if you don't find one, just use an alternative.
I found even complete ignitor sets including coils and impuls sensors, starting at roundabout 55 bucks.
Here's an example for an alternative, where the characteristics of the proposed bikes are perhaps also quite good for the XS400DOHC:
Motorcycle Digital Ignition CDI Unit For Suzuki GSX400 GSX 400 S katana 92 93 RF400 RF 400 R GK78A 93 96 Stable Output Igniter|Motorbike Ingition| - AliExpress
Pickups, if defective, might be replaced through a very cheap alternative with infrared; 2 pickups for 1.80 ;-)
If you check out aliexpress, you will find all you need, at least after a while...
Today, I checked aliexpress for carburetors, because I got probs with both, my Keihins for the Hondas and my Mikunis for the XS400SE and 12E/16M.
I found alternatives which are cheaper, including the shipping costs, than the cleaning of the old ones alone!
However, if aliexpress (or just: the chinese sources, for political correctness or whatever reason) is not the right source for you, IgniTech might be the right choice. At least here we are 2 people who would recommend that ;-)
Good luck and best regards from Germany !