2005 YZ250 Top End Notes

[bedell99]

Dominater. It always seemed like a good oil. It lubricates great. I just really think I just had to many hours on the bike, but I'm definetely going to use Steves advice and try a new oil.

Erik

 

[NO HAND]

...but I'm definetely going to use Steves advice and try a new oil.

Erik

That's a very good idea. Polyolester really is a huge progress in oil technology but unfortunately it is also very expensive. That's why only a few oil companies have started using it yet.

 

[bedell99]

Actually POE oil has been used in the HVAC industy as lubricant for refrigerant for years. I know Trane uses it in there R-12 and R-134A refrigerants as an oil for the compressors. I think now it is just being used as a 2-stroke oil which makes sense.

i went riding today. the biggest difference in performance though that i noticed was in the top end. i think the cometic gasket might be a bit thicker, because this baby was revving great on top. No loss on bottom either. Just running real crisp.

Erik

Erik

 

[pokemanyz]

The only difference between an A piston and a D piston is .0005......YZ 250's are a bit on the loose side, so no problems with a D piston in an A cylinder.

The difference between an A and B piston is .00016 thats pretty close to nothing.

I stand corrected !

I was going by memory since I don't have a Yamaha anymore.
I thought it was a .005 difference. :moon: :blah: :bang: