1985 550 pistons in a 550 motor

[drexer13]

I was wondering if anyone has tryed to use the pistons out of a 1985 550 motor in an 1980 550 motor. The bore on the 85 motor is 5mm larger and the rings are significantly cheaper and easer to find. I thought this might be a good alternative to buying over sized pistons.

[tkent02]

The 1980 550 is an eight valve engine, the 1985 is sixteen valve?

The piston shapes would be completely different.

If you want more displacement go with the 650 top end.

[drexer13]

I was under the impression that the only top end that would fit on a 550 was a 550.
Is there any way you could direct me to a thread that will tell me otherwise?

The idea really wasn't about getting more displacement it was more about being able freshen up the engine without spending a butt ton of money.

[cowboyup3371]

If you are trying to update things just renew the gaskets, lap the valves, and make sure everything is still in spec. Take a look at my 550T rebuild thread in the projects section as that's what I'm doing (my base gasket was leaking).

Also, put your bike info in your signature block and a location in your profile so we can provide better help, maybe even onsite if you're close to someone that is willing to do that.