Inspected my old brandnew R277 has the caged bearing installed.
The engine not yet broken-in, I thought of changing to cageless bearing..
What bearing size should it be? LEAF has rotax cageless bearing in stock but intended for R503 and not sure this will fit into R277. Any thought? Thanks in advance.

Regards,

Phil

I was about to write that they would probably not fit, but then I came across this Service Information from Rotax that says the piston in an 277 engine are the same size as the 503 pistons! That was new to me. So I guess that there is a good chance that the cageless bearings from a 503 will fit in a 277

Phil the pin bearings are the same. If you install them on an upright engine make sure to put a rag over the crankcase opening and use a heavy grease to hold them in position. I made a tool out of a old piston pin by cutting it to the width of the con rod. Saves a lot of time.

CPS  print confirmed the exact part #.
Monte, thanks for installation tips..😊
Petter, I'm happy to know that 503 and 277 had few parts in common😊... probably
and hopefully cylinder bore sleeve may match as well😊

Best Regards,

Phil

LEAF item part#

from what I understand, the 277 is essentially half a 503 in many respects.

Phil, I hope that the earth quake had no effect on you or yours. There is a piece in the latest Sport Aviation about Bing 54 carburetors. There are tables showing the needle and jet sizes for the different size engines.

Did a little search on the cageless bearing.For what its worth all the manufacturers like suzuki/honda/kawasaki make this bearing.Someone wrote  
that an equivalent kawasaki bearing costs 10$.
But then maybe Rotax makes a very high quality part.