COP's Harness pics

[Bon-86]

No offense taken.

I don't have any facts about the old transistors but apparently you do. If they are 16 amp amp max transistors, fine. They do need to be derated somewhat for temperature though as they live next to a hot engine and do get a pretty good heat soak. I did see somewhat lower amperage through the COPS than the V/R would suggest. The on resistance of the power transistors, wiring and connectors account for the additional IR losses that you refer to in your experience. I'm not going to subject my TCI to the test to get a scope trace to prove differently.

yes, some designs are above the usual design criteria of 50% rated limit as most circuits are designed to cost above all. Component manufacturers derate and circuit designers derate again. It comes down to manufacturing tolerances and environment. Japanese automotive electronic design is extremely conservative and, for example, Chrysler is not. In the long run it makes all the difference between reliability and increased maintenance.

I have performed an autopsy on a dead TCI box and found it to be the driver rather than the power transistors. I looked and looked for a replacement chip but failed to find one as the part is long ago obsolete. I did find some sites listing it but none actually had any stock.

 

[Duke86max]

So what is the bottom line here? I'm new to these bikes and got a set of the Denso cops from a GSXR 1000 and was waiting to get a harness but I don't want to burn up anything.
My coils under the seat are showing bare wires and need replaced badly. I'm trying to decide whether to get the harness or to just replace the coils with Dyna if I can find them. If this is a solid and reliable fix I'll do it but if not I'll just get the coils.
Thanks
Duke

 

[naughtyG]

I've been using the longer Denso COPs on my '86 with the original TCI and no resistors.

Done the best part of 7000 miles and no probs yet with ignition.

The pros for COPs are indeed:
- way easier and cheaper to replace than OEM coils
- no more HT leads and spark plug caps to go wrong and replace
- slight weight loss if you remove all four old coils
- more room for your balls where the rear coils used to live

 

[Bon-86]

I suppose Przemek and I will see the solution differently as I suspect we come from different backgrounds. I'm pretty conservative when it comes to these issues and would rather err on the side of safety. Przemek's experience seems to tell him it's okay to go without a resistor and my analysis indicates that at least a 1-3 ohm resistor is prudent.

I'd say this:

If you want to go with COPS then I'd go with the Denso's that are around 1.5 ohms.

If you want your Max to see the same workload when firing the plugs then a 1 ohm resistor with the Denso's will work just fine. The COPS will produce a very strong spark.

If you want to go easy on your TCI box then you could go with 3 ohms. You'll still get a strong spark by industry standards.

If you want the absolute maximum spark per stroke then no resistor is used.

You'll love the COPS in any case. The harness from 88VMX12 will sure make the installation way easier for sure.

 

[pumacorp]

Stock coils are 3 ohms...So if u have a 1.5 ohm cop why not just goto 1.5 ohm resistor ????
I did it and so far I logged 900 miles and thats with a dyna and riding hard on track days...

3 ohm resistor I cant see making anything better...I talked to dyna about this and they agree as long as their box sees 3 ohms they should be fine..

 

[sdt354]

Where can I find the white plugs? I'd like to keep my coils in tact. Anybody?
Nice looking harness you made.
Steve-o

 

[sdt354]

OEM'S are yellow

 

[88vmx12]

ok I have made a few harnesses without the resistors, and am waiting for the resistors from a supplier. I also have another round of connectors coming. I am hoping to have them the middle to the end of next week. All harnesses that I make from now on out will have a resistor. I have purchased very small and high quality resistors for these. Since I am adding resistors I have to up the price to $70 per harness set. The resistors were $5 each my cost even when I ordered 100 of them . So I am only adding the resistor cost to the original harness price. I am sorry this has taken as long as it has to get these together. Originally I was ready to go , then a few of you guys had concerns about ignition failure. Thanks to Bon and Satarial their imput has put a rest to this issue. I expect to have all components in hand by the end of next week. As of right now I have purchased all the resistors that I can get my hands on. I even went to manufacturer and they are a built to order. My source that I found via the manufacterer has some in stock. now once these are gone it will be 7 weeks out before the next ones are available. I guess I could have chosen a lower quality resistor and had access to more resistors , but I believe in building something that will last!
Thanks for your patience

 

[88vmx12]

Where can I find the white plugs? I'd like to keep my coils in tact. Anybody?
Nice looking harness you made.
Steve-o

Steve , are you wanting to make your own harness? If so I will have some plugs available after my order comes in . I had to buy 1,000 pcs :bang head:

Gannon