CDI differences...

[jcs003]

i have a CDI from my 86 and came across a CDI from an 85 atc. the connectors all match.

question is: are there any benefits to the atc CDI? is it compatable? will it work, but cause ignition issues?

[jcs003]

Originally posted by jcs003
i have a CDI from my 86 and came across a CDI from an 85 atc. the connectors all match.

question is: are there any benefits to the atc CDI? is it compatable? will it work, but cause ignition issues?

anyone???

[k265r]

it will work and i dont recall any differences.

[jcs003]

Originally posted by k265r
it will work and i dont recall any differences.

the thing i forgot to mention was the atc CDI is smaller:confused: :confused:

[wilkin250r]

The 85 ATC engine is almost identical to the 86 TRX engine. I think there were a few small internal changes, but nothing major, I think 90% of the parts can swap back and forth.

If the engine is almost identical, then I can't possibly imagine the CDI is terribly different. It might have a slightly different curve, but I can't see any way it could possibly cause problems. If they're basically the same engine, they HAVE to be basically the same CDI, right?

[zedicus00]

85 and 86 are 100% interchangeable between them. there are some cdi's with a different plug but if you change the plug even they work. the diferences come in after 88 and ive had issues trying to use 88-89 cdi's on older engines and vice versa. not to say it cant work, there too though.

hoe all that made sense, typed ina bit of a hurry.

[jcs003]

ok...this is what the honda guy told me. the atc will rev higher and the hit will come sooner. not sure if he was accurate.

one thing i know for sure is its an 85-86 atc CDI. electrical plugs confirm this.

bottom line is, it is compatable but may change the power delivery:confused: i know this is an issue with the cr250r ignition system...

[zedicus00]

the 85 engine has a bit lighter flywheel and bit different compression ratio. as is that engine would have different revability and power delivery. this has nothing to do with the cdi itself but might be percieved that way if comparing engine characteristics.

there COULD be differences in the CDI, the only way to know for sure would be to try them on a dyno on the SAME test machine.

i do believe that you could use iether and still have a good running atv, the only time ive seen problems is when trying to use an 88-89 on an earlier engine. or an earlier engine cdi on an 88-89 engine/electronics.

[deathman53]

85 and 86 cdi's have different connectors. A 85 cdi won't work on a 86-. A 86-cdi won't work on a 85 harness. A 85 cdi is a simple round plug 6-pin and a 86- cdi is 2 plugs, one is 4 pin, other is 2 pin. 85 was one year only for some parts, wiring, swingarm ***., carrier, brake linkege, suspension linkege, axle, and there was something else(don't remember it).

[2fiftosR]

Deathman is right the 85 CDI is only good for the 85.

jcs003 if you decide to sell the 85 CDI pls let me know im after one myself.