cdi/tci/coil question

so i switched my 81 xj650 motor to an 81 xj750 motor. rejetted the carbs, switched the cdi to a tci box.

got spark on all four but bad firing on 1+4. good firing on 2+3. good compression etc. valves good, carbs good, fuel good, air good. timing good

was reading the electrical testing diagnostic and it was talking about cdi vs tci coils... now I'm wondering if i need to replace my old 650 cdi coils with new tci coils. this would be due to the lack of a dwell period in cdi coils, which the tci unit controls...

any thoughts?

 

They both use TCI ignition. I don't have time to double check this morning, but I believe the ignition coils are the exact same part.

I'm assuming the ignition system was fine with the 650 engine in? Unless you damaged something switching the mills the coils should be ok.

You might stick the 650 TCI back in to see if your spark problem clears up. The 650 TCI will run the 750 engine, the advance curve is different is all.

Of course you got a different set of pick up coils with the 750 engine. If it doesn't run right with the 650 TCI I'd be checking the pick ups closely.

 

thanks micarl. gonna hafta dig thru the storage shed to find that old tci box.

when you say "checking the pickups closely" what exactly do you mean?

 

The 1980-81 650 TCI box has a black label on it, and is marked:

TYPE TID14-02
4H7-10 (date code)
4 + 4 terminals


This box is designed to be used with the pick-up coils that have the following resistance specs:

700 ohms +/- 20% (all non-yics 650cc engines)



The '82-84 XJ650 Maxim and all the 1981-83 XJ750 models use the same TCI box, it has a red label, and it is marked:

TYPE TID14-06
5G2-10 (date code)
4 + 5 terminals----one extra terminal for the sidestand switch relay, which the 1980-81 650 models did not use.

This box is designed to be used with the pick-up coils that have the following resistance specs:

650 ohms +/- 20% (all 550, 650, 750 yics engines)



The 1982 XJ650RJ Seca used a TCI box all it's own, it has a green label, and is marked:

TYPE TID14-08
5V2-10 (date code)
4 + 5 terminals



Note that 650RJC models (Canadian) bikes that use a YICS engine probably use the red-label 5G2-10 tci box, but I'm not 100% sure on that......


We've found that swapping around the 4H7-10 and 5G2-10 boxes results in a small change in performance (as MiCarl says, due to differing advance curves).

 

would i be able to use the TYPE TID14-02
4H7-10 (date code)
4 + 4 terminals
on my 1982 maxim 650 im pretty sure its a yics engine

 

The 4H7-10 box does not have the terminal for the sidestand safety relay, and will defeat that system, when used on a bike that originally had the 5G2-10 bike.

We've found that swapping around the 4H7-10 and 5G2-10 boxes results in a small change in performance (as MiCarl says, due to differing advance curves).

 

MoonFried, what kind of problems are you seeing on 1-4? You mention a misfire. Do the coils ohm out correctly? Did you swap them with 2-3 and get the same result? If you see a misfire on the the 1-4 ignition coil and it ohms out right, you may be suffering with a TCI problem. If the sparks are good with the 2-3 coil pack substituted, you have a coil problem. I don't think you have a pickup coil issue if you get the 2-3 coils to work with 1-4's input plugged in.

 

Hi, im a new guy on this forum. I need help with my 1981 Yamaha 550 YICS I have been struggling to find a replacement TCI/CDI type TID14-05 4U8-10. Would anyone know if I can use another XJ Yamaha type?

 

Hi ZHYRUZ, the XJ550 tci unit is unique to that engine. We should have a good used one in-stock, send me an e-mail for pricing/ordering info: info@xj4ever.com

 

Thanks Chacal for the info I will contact you soon

 

Do you have any more of those boxes available?