Not reaching top speed

Ive been doing some thinking (i do the best thinking in my head) about my ignition set-up for my bike. Ill share some of my thoughts:

I want to fix my ignition/timing issue. I believe I have several options:

  1. Have the Stock TCI investigated by a company. Costs €50. Im expecting it to be faulty (not advancing) but this test will make sure this is the problem.
  2. Having the original TCI repaired by the same company, adds another €170. The thing i dont like about it....still a lot of +40year old components on it.
  3. Buy a reproduction TCI from this company. Plug and play Just a new TCI with modern components. €300
xs650 carmo ign.jpg

This is an easy option, i dont need to replace anything else on my bike. However, some of the original parts on my bike have not always been very reliable. The TCI has failed me before (5 years ago). last year the charging system sh*t the bed. in other words: i'm not a huge fan of the original charging system. So spending 300 euros will sort ignition but keep my original charging system.

Ive been looking into after market ignition options. I don't like points, i don't want a system on the camshaft. I narrowed it down to 2 options:

4. Powerdynamo ignition + alternator system. I like this a lot. It looks well put together, 180W output, there is a decent manual and cant read bad reviews on this forum about it. Only downside... costing quite a lot of money at €550
Powerdynamo ign.jpg
5. Electrix ignition + alternator does basically the same. only outputting 50w but can be run without a battery. Cant find a whole lot of reviews about this system online. Price €300
electrix ign.JPG


What are your ideas? Do you have any experience with one of the two systems stated above?
 
What would a real PAMCO iggie run you over there? as for the alt., a Fiat 124 voltage regulator and a 3 phase rectifier and your charging your battery cheaply with new parts.
 
What would a real PAMCO iggie run you over there? as for the alt., a Fiat 124 voltage regulator and a 3 phase rectifier and your charging your battery cheaply with new parts.
 
Hi. Both Powerdynamo and Electrex, systems are viable solutions to your problem but, at a great deal of money. Powerdynamo would be my choice, as a last resort.
The only experience I have of an electronic system not advancing is when the trigger wires have been swapped round by mistake, don’t ask me who’s. This occurred on a Boyer system, it may not be the case with Yamaha TCI, just a thought.
 
How about tracking down a proper functioning original used TCI to see if that solves the issue? Don't know what they go for but imagine not more than €50-75? You might get a bunch more years out of that. If it doesn't solvd the problem of no advance (or not reaching top speed), then you would know to look further. Maybe good used ones cost much more tho, I haven't tried looking for one.
 
I don't want a pamco. Nor is my faith in the original TCI very high.

I checked the continuity of the pick up as far as I could. I don't think you can open the pick up itself though.... No way to rule it out completely.
 
My TCI has been tested by an external company. Turns out It's broken. It does not advance the signal coming from the pick up. And it keeps the wire to the coil open for too long.

Guess I'm looking for one of the alternatives
 
At least you figured out the problem.
Although I am not looking to 'moderrnize' my '76 point ignition, when I did so on a '69 oldtimer Mercedes, the effect on how the engine ran was significant. I installed an electronic ignition (from the Dutch company 1-2-3) and the results were really noticeable. It even allows to program different advance curves and actually adjusts the timing slightly as it senses how the engine is running, altogether it's much superior to the old-fashioned points system.

As I said, I like the way my '76 XS engine is running with the original points system and I like that it's original, as the bike is also otherwise almost 100% original with 5,000 miles on it, but this is one upgrade I would seriously consider.
 
I decided to go with a new replacement ignition box from Carmo.

I do like the set from power dynamo but it's 300 euro more expensive and more work to install. I would have to partially rewire the bike and remake brackets for stuff like the coil and ignition box.

I did some more reading on the whole alternator subject and figure that while the parts on my bike are not new, the technology is proven and should be ok. This made me choose the replacement option.

Looking forward to riding/testing it! I'll report back when everything is working.
 
I would have done same. Good call. I'm a fan of the post 80s ignition deal.
 
Any other Yamaha TCI units suitable for use, or modifiable for replacement?
Thinking out loud here..... Anybody ever try to get one of PamcoPete's module to fire off the TCI timing sensor? They're both hall effect triggered as far as I know. One of Petes little boards would make a pretty inexpensive replacement.....
 
I think Pete's unit is highly dependant on the 60° spacings of the magnets in the camshaft rotor. That would be 120° at the crank. The XS TCI trigger coils look to be about 45° spacing, at the crank...
 
If anybody is interested in the old TCI let me know. maybe to fiddle with it or try to repair it. Disclaimer: it runs but does not advance and keeps the signal to the coil open for to long.

Otherwise ill throw it in the art bin
 
Just did a short testrun.... Omg it's like a different bike! Can't believe how much more pulling power it has! I was able to reach 165kmh without any difficulties. So far I'm stoked! The new ignition seems like a nice piece of kit.

IMG_20190323_085232730.jpg


The next thing I want to work on is the reversion I'm still seeing from the intake side. I'm going to investigate the cones next. I was hoping the ignition was the cause of it all. Secondly I can't seem to re-test the timing. Somehow the light is not picking up the signal 100% of the time.

 
Did you try your timing light on both spark plug wires? Some timing lights like one better than the other. The spark signal on your dual coil flows down one plug wire to the plug, through the engine to the other plug, then back up the other plug wire to the coil again. That makes the polarity on one plug wire positive, the other negative. Some timing lights are sensitive to this and prefer one polarity over the other.
 
Just did a short testrun.... Omg it's like a different bike! Can't believe how much more pulling power it has! I was able to reach 165kmh without any difficulties. So far I'm stoked! The new ignition seems like a nice piece of kit.

View attachment 137460

The next thing I want to work on is the reversion I'm still seeing from the intake side. I'm going to investigate the cones next. I was hoping the ignition was the cause of it all. Secondly I can't seem to re-test the timing. Somehow the light is not picking up the signal 100% of the time.

On that fog of fuel coming out of the carbs, it seems it happens as the slides rise at least as far as slide needle adjustment range or maybe the beginning of main jet control......I would drop the needles a notch and see what that does.....You might have to open the low-speed adjuster screws a bit more after this but it could help and is fully reversible if not getting the result you want.....
 
Did you try your timing light on both spark plug wires? Some timing lights like one better than the other. The spark signal on your dual coil flows down one plug wire to the plug, through the engine to the other plug, then back up the other plug wire to the coil again. That makes the polarity on one plug wire positive, the other negative. Some timing lights are sensitive to this and prefer one polarity over the other.

I tried the pick up of the strobe on both leads. RHS is no flashing whatsoever. LHS seems to flash when it feels like it haha. Don't know why this is.

I'll give the company a call next week.
 
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