26H/41R "swappable"?

[Great White]

So I know the 26H and the 41R CDI boxes are not swappable "as is".

 

But it seems the major point is the vacuum advance being ported vacuum in the 26H (IE: in the carbs) and manifold vacuum in the 41R (IE:after the carbs).

 

Does anyone know if it is possible to swap the 26H/41R CDI boxes if you move the vacuum advance source?

 

Maybe I should get out the wiring diagrams and have a closer look....

[dingy]

You can use a 1984~1989 TCI on a 1983 bike by moving the vacuum line from the #2 carb to the plugged #2 intake & plugging port on #2 carb.

 

AutoZone sells cap that is needed.

 

It is not easy to move a 1983 to 1984~1989 bikes as the port is not on the 1984~1989 carbs that is needed.

 

The 1983 TCI MUST have the vacuum source originate from above the throttle plates. The 1984~1993 TCI MUST have the vacuum source originate from below the throttle plates. 1990~1993 TCIs will not work on any other bikes without rotor, pickup coils and harness changes.

 

Gary

[Great White]

Cool, just what I needed to know.

 

My 83 runs a 26H, but I have several spare 41R's.

 

I'm going on a trip and may throw a 41R in the bags just in case.

 

Cheers.

 

[Venturous Randy]

I have a 41R on my 83 and as Dingy stated, I plugged the carb port and moved the hose to the #2 manifold. I still carry my old 26H TCI with me as a spare if I ever have to use it.

Randy

[Great White]

I have a 41R on my 83 and as Dingy stated, I plugged the carb port and moved the hose to the #2 manifold. I still carry my old 26H TCI with me as a spare if I ever have to use it.

Randy

 

Cool.

 

I have my original 26h and running fine.

 

I have 2 spare 41R's now.

 

I figure one will be a spare, the other I have some...."plans"......for......

[dna9656]

Stop counting on 31 year old solid state electronics! Get a Ignitec! They're the BOMB!!!

[Yammer Dan]

I still have my New ones From Dingy on the shelf. I got plans but hate to mess with electrical when its working.

[Great White]

Stop counting on 31 year old solid state electronics! Get a Ignitec! They're the BOMB!!!

 

Nothing wrong with solid state electronics.

 

pretty much bullet proof, when given even the most minimal care (even neglect) and they're pretty easily repaired when they do go down as opposed to surface mount components on today's stuff. When surface mounts craps out the average joe is throwing it out. I just pull out the multimeter and start troubleshooting on older stuff.

 

not to mention they go 30-odd years before they even start giving you trouble. Hard to beat that kind of service record.

 

theyre not without thier drawbacks though. "State of the art" in thier time, there are options with far better resolution these days. You're also limited to what they are. Ie: you're changing components (or burning chips) to adjust things.

 

Main attraction the ignitech box has for me is the customizable ign curve, adding the vboost control and more compatible with coil on plug.

 

Edited July 14, 2015 by Great White

[Great White]

I still have my New ones From Dingy on the shelf. I got plans but hate to mess with electrical when its working.

 

I hear that!

 

my 83 is running strong and solid. This winter I'm planning to swap on a venture royal wiring harness. But the bike is running soooo well I'm having second thoughts....

[dingy]

I hear that!

 

my 83 is running strong and solid. This winter I'm planning to swap on a venture royal wiring harness. But the bike is running soooo well I'm having second thoughts....

Been there done that.

 

You will need all 3 brake/clutch switches, clutch & throttle hand controls switches, CMU unit, thermostat unit. All that I can think of.

 

Guessing you might be wanting to add cruise control, that's what I did it for.

 

Gary

[Great White]

Been there done that.

 

You will need all 3 brake/clutch switches, clutch & throttle hand controls switches, CMU unit, thermostat unit. All that I can think of.

 

Guessing you might be wanting to add cruise control, that's what I did it for.

 

Gary

 

 

Yessir. I bought a complete 86 royale that someone had already removed the engine. Been slowly going through the harness and fixing/freshening/cleaning it. I'm also going to add the CLASS system. Air is not my prefered way of handling suspension changes, but this is a touring bike, not a sports bike. I can accept the air suspension for the versatility it will give me.

 

[dna9656]

Nothing wrong with solid state electronics.

 

pretty much bullet proof, when given even the most minimal care (even neglect) and they're pretty easily repaired when they do go down as opposed to surface mount components on today's stuff. When surface mounts craps out the average joe is throwing it out. I just pull out the multimeter and start troubleshooting on older stuff.

 

not to mention they go 30-odd years before they even start giving you trouble. Hard to beat that kind of service record.

 

theyre not without thier drawbacks though. "State of the art" in thier time, there are options with far better resolution these days. You're also limited to what they are. Ie: you're changing components (or burning chips) to adjust things.

 

Main attraction the ignitech box has for me is the customizable ign curve, adding the vboost control and more compatible with coil on plug.

 

 

Solid State electronics; they are EXTREMELY reliable for a time, a LONG time! BUT then they start to decompose, values of the individual components change, resistors (Resistance is futile), increases or decreases, diodes stop functioning, capacitors stop holding a charge, proprietary chips short out, you can't tell by looking. A solid state ignition can't be fixed in most road side scenarios, trust me; it won't quit on you in the driveway just before a road trip. The thing about solid state VS points, a coil and a cam is you can replace points and a coil on the side of the road. I wouldn't care to be doing that with a stock TCI in it's stock location. A lot of guys move them to a more accessible place and that's cool. I'm just saying NEW ones aren't available. The Ignitec Ignition is. I have been on too many dark, cold, snowy/rainy roads in BFE and had the car break down due to old and/or cheap parts. This was back in the day before Cell phones. I learned not to depend on old parts. Ignition modules in cars go bad, you never know when it's going to happen. So a younger part is more reliable than an older one.

[Great White]

Solid State electronics; they are EXTREMELY reliable for a time, a LONG time! BUT then they start to decompose, values of the individual components change, resistors (Resistance is futile), increases or decreases, diodes stop functioning, capacitors stop holding a charge, proprietary chips short out, you can't tell by looking. A solid state ignition can't be fixed in most road side scenarios, trust me; it won't quit on you in the driveway just before a road trip. The thing about solid state VS points, a coil and a cam is you can replace points and a coil on the side of the road. I wouldn't care to be doing that with a stock TCI in it's stock location. A lot of guys move them to a more accessible place and that's cool. I'm just saying NEW ones aren't available. The Ignitec Ignition is. I have been on too many dark, cold, snowy/rainy roads in BFE and had the car break down due to old and/or cheap parts. This was back in the day before Cell phones. I learned not to depend on old parts. Ignition modules in cars go bad, you never know when it's going to happen. So a younger part is more reliable than an older one.

 

Ther is truth in your statements, but I also rebuild electronics as one of my hobbies sooo....

Edited July 15, 2015 by Great White

[BlueSky]

So, is there any difference in the gas mileage between the 26H and the 41R?

Is there any difference in the performance?

 

Usually, hooking the vacuum advance up to the manifold vacuum improves gas mileage if the curve is set right. But, you need enough advance without the vacuum advance for acceleration because the vacuum goes away with full throttle. I used to set my cars up for 30 something degrees advance with the initial setting and the centrifugal. then with the vacuum advance hooked to the manifold, the total advance could be as high as 50 degrees while cruising at low rpm under lean light throttle conditions to improve mileage. At full throttle with a richer fuel mixture, usually 30 something degrees advance was ideal for acceleration.

[Great White]

So, is there any difference in the gas mileage between the 26H and the 41R?

Is there any difference in the performance?

 

Usually, hooking the vacuum advance up to the manifold vacuum improves gas mileage if the curve is set right. But, you need enough advance without the vacuum advance for acceleration because the vacuum goes away with full throttle. I used to set my cars up for 30 something degrees advance with the initial setting and the centrifugal. then with the vacuum advance hooked to the manifold, the total advance could be as high as 50 degrees while cruising at low rpm under lean light throttle conditions to improve mileage. At full throttle with a richer fuel mixture, usually 30 something degrees advance was ideal for acceleration.

 

 

Dunno. I'd have to see if there's anything of a "program" anywhere on the board and I'd have to see what's in it. I haven't had any of the TCI's I have apart yet (have 4 now) but the few pictures I've seen of the guys don't seem to show a chip on the boards. It may be all defined by resistance and solid state switches.

 

Probably a simple chip on there somewhere, and it's probably holding a very basic program. the presence of a MAP sensor instead of a vacuum pot seem to indicate there's a programmed chip in there somewhere. All the this "electronic stuff" was still pretty pretty primitive in the 80's.

 

I've kind of got it in my mind to pull one TCI to bits, suss out any programs, brute force the bin file off the chip, drop a ZIF socket on the board and then have a programable TCI. Kind of like working with obdI ECM'S again. The ignitech sounds like it would be like working with OBDII with flash able chips on board.

 

Ported or manifold vacuum doesn't really matter if the program is written for it properly. Most automotive manufactures use manifold vacuum though. Usually a stronger signal to the vacuum pots they used to use for the advance mechanism when it was mechanical and spring defined ign advance curve.

 

I've got to spend some time with the TCI guts to see how it works, but I'm too busy riding this summer. Winter will give me some time to see what I'll see.

 

Edited July 15, 2015 by Great White

[Great White]

Been there done that.

 

You will need all 3 brake/clutch switches, clutch & throttle hand controls switches, CMU unit, thermostat unit. All that I can think of.

 

Guessing you might be wanting to add cruise control, that's what I did it for.

 

Gary

 

Wait: why do I need the thermostat unit? It's not in any of the block or wiring diagrams I've seen...

[Flyinfool]

Yes there is a programmable chip in the TCI. Might be 2 of them?

When one of the 8 diodes fails this chip is destroyed by the back EMF coming from the ignition coils. The chip itself is available, but the program is not. Now if you can somehow peel the program off of that chip then there are a lot of dead TCIs around that could be repaired.

[Great White]

Yes there is a programmable chip in the TCI. Might be 2 of them?

When one of the 8 diodes fails this chip is destroyed by the back EMF coming from the ignition coils. The chip itself is available, but the program is not. Now if you can somehow peel the program off of that chip then there are a lot of dead TCIs around that could be repaired.

 

Well, depending on how old it is a fella should be able to just download the .bin file from the chip.

 

Once you have it, you can do nearly anything you want with it. Assuming you can work in hex...

[Flyinfool]

I will be looking forward to see what you can get out of it. I am really bad at software so I leave that to others.

[Great White]

Yes there is a programmable chip in the TCI. Might be 2 of them?

 

Got a pic of one?

 

I haven't had one apart yet myself, but from the available pics on the net all I've seen is mostly through mount caps, diodes, resistors and transistors.

 

There does look to be two 40 pin "cards", but they look to pretty much just hold surface mount resistors and such.

 

Boards that sensitive to back voltage o would think should have " protection" diodes (like a 1N4003) . They blow if back voltage is induced, protecting components upstream. Pretty common in things like cb radios. Don't ask me how I know that.....

Edited July 15, 2015 by Great White

[10spd]

Stop counting on 31 year old solid state electronics! Get a Ignitec! They're the BOMB!!!

This is true. I have no trouble with mine

[Great White]

This is true. I have no trouble with mine

 

Glad it works for you.

 

I may end up with one myself to get vboost control.

 

But it costs me nothing to play with the couple tci's I already have on hand...

Edited July 15, 2015 by Great White

[10spd]

I just wanted mine to run right. You know Rev up around 4500+. It wouldn't before.

[Great White]

I just wanted mine to run right. You know Rev up around 4500+. It wouldn't before.

 

No problem, everybody takes whichever route works best for them.

 

My old tci has no problem firing the plugs well past redline....

[dingy]

Wait: why do I need the thermostat unit? It's not in any of the block or wiring diagrams I've seen...

83-85 is single wire connection, 86-93 is two wire connection to fan relay.

 

Not thermostat itself, but a sensor in coolant junction block, bad description on my part.

 

Gary