atc motor into a trx

[brandonpeake]

if this has been covered a million times i am sorry and i did search i was under the impression it would bolt into thre trx frame but do you need the complete atc engine and compoonents or will the trx ccomponents bolt up to it?

[86 Quad R]

both '85 and '86 ATC engines will bolt into the trx frame.

[mineralgrey01gt]

i have an 86 atc engine on my 86 trx 250r, bolts up perfect and I used a harness from a 87-89 (with the key)

[wilkin250r]

I believe some of the wire harnesses are slightly different, but they can be easily modified.

I also believe (but double-check this one) that the CDIs have slightly different timing curves, but the can still be interchanged. The plugs are all the same.

The motor internals are slightly different year-to-year, but they outsides are all identical, and can swap into any frame, any year.

[Rip_Tear]

I'm pretty sure the CDI's are interchangeable. The guy I got my trx 250r from was using the CDI from it on an ATC 250r.

[eddie pettengil]

I have made the change many times from my 86 atc motor into my 86 trx frame and the trx motor into the atc frame. One motor is completely stock the other a little modded. all I have to do is rotate the exhaust flange on the motor so the exhaust springs have a place to connect too.

[86 Quad R]

you guys are correct about the CDI's. there is a bit of difference in the spark curves. im currently running a 85 engine in mine with all of the matching ignition. it seems to deliver a better torque than with the trx CDI.

if/when switching from a TRX(square pin) to the 85 ATC CDI(round pin) you'll need the corresponding harness end to go with it. the swap is esy enough. ya just coordinate with the wiring schematics of each year.

i have found that its best to match all year components together. if ya use a '89 engine/stator/fly wheel, its best to use the CDI for the '89 an so on en so forth

[zedicus00]

correct on the electronics/stator/flywheel working best when matched.

on a side note the flywheel in yur 85 engine is about 100 grams lighter weight. that would count for some added torque feel.

[86 Quad R]

Originally posted by zedicus00
on a side note the flywheel in yur 85 engine is about 100 grams lighter weight. that would count for some added torque feel.

true that :devil: