View Full Version : Will an 85 ATC250R motor work in a 88/89 quad?

11-28-2002, 04:28 AM
Was just wonderin if it will bolt in with no mods. Are the quad motors stronger? What are the differences between the 2?

11-28-2002, 09:44 AM
The 85 motor is identical to the 86-87 except it has a slightly higher compression ratio.

11-28-2002, 11:10 AM
in answer to your question, yes it will. the differnce will come when you mount your motor in you won't be able to make use of your rear engine mount. there are still three other mount's you will use just not the rear. that is all because they canged the swing and the swing arm mount in 88.

11-28-2002, 01:14 PM
They all have those extra holes. 88-89 had them too but didn't use them.

11-28-2002, 04:13 PM
To clarify, the motors are NOT identical. Honda made subtle improvements to the engine throughout its production run. I will not go into details, but I can assure you the Atc engine (85 or newer of course) will bolt right into any Trx250r chassis.

11-30-2002, 07:36 PM
yepper... they will bolt right in.. that is why you see the rolling chassis's for sale for the atc 250r.. they steal the motors from the atc's to put in the trx...