engine parts

[jwjethro]

will motor parts from an 81 special work on a 79 motor.

[skids]

Re: engine parts

The pick-up coils from the 81 must be swapped with the brain box. Also the plug wire coils from the 81 should be used if you use the aformentioned parts because you will be bipassing the ballast resistor.

There are differences between side covers, seat pans, and the footpeg brackets (I think).

The valves from the 81 intakes are bigger diameter, but I think you can swap out the complete head.

The cams are different.

The valve shim clearance specs are different.

The air box on the 81 will be plugged for the breather nipples.

The carbs are a bit different, including jetting and float heights.

The 81 rims will be tubeless if stock, the 79 will need to be checked.

The 81 will have an emergency flashed switch.

OK, this is a little beyond what you asked for.

Originally posted by jwjethro
will motor parts from an 81 special work on a 79 motor.

[mro]

motor parts

Lower end up to pistons same.
81 pistons will work, but should have all one year
(78/79, 9.2 verses 80/81's 9.0 to 1 compression)
Carbs will swap if changing entire bank.
Heads are interchangeable, tho cams/valves are slightly different.
Can swap cams between heads but not valves.

Plus what skids said covers about 95 percent of differences


mro