I see Klotz is still around...

[flatplains]

I too think it would be strange if R50 has changed. I started using it likely 2016ish. Before that Amsoil dominator was good too, but it was almost twice the price of R50. Today if anything Amsoil is cheaper. Not sure what happened there.

I don't keep pictures, but here is the piston from my last top end. This was nearing 200 hours in my Gas gas Ec300. It's as clean a piston as I've ever seen. Only light stains near the rings, no carbon at all. The power valve had carbon on it, nothing unusual. My Lawnboy looked just as good, and that's been going for years running about 1.5 hours per week, every week.

 

[flatplains]

If I didn't say already, this is 40:1. I had the squish adjusted by taking down the head, and bumped up compression at the same time. 91 octane isn't quite enough. This piston only saw 100LL Avgas.

 

[bwalker]

Dependant on fuel ( gas vs alcohol ) 50 hrs was max within sled tear downs for decarbonizing . Some cycle teams in the open class always tore down weekly vs every two weeks . On a race weekend a oval sled engine could see 10 hrs run time easily between time trial , 5-10 lap heat races & 25 -50 lap main feature race dependant on the race venue . A Enduro / xc sled would do the same in one single event . Eagle River & Peterbough & Alexandria would easily be over 50 engine hours not even including tuning tech time . If your putting that amount of hrs with no deposit or gumming than the recipe has definitely changed ,
perhaps an ester additive package in the new R50 ?

Many guys using R50 or other high temp oils for that matter,in saws are tuned so rich that the piston is washed clean. They then proclaim the oil to be the best based on a bare metal piston. Any oil can do this.
R50 hasn't changed at all from the late 90's that I can tell.
I think some guys are under the illusion that their is constant R&D on two cycle oils. This isn't the case as the 2-cycle motor is in great decline usage wise and has been for a long time.

 

[bwalker]

I too think it would be strange if R50 has changed. I started using it likely 2016ish. Before that Amsoil dominator was good too, but it was almost twice the price of R50. Today if anything Amsoil is cheaper. Not sure what happened there.

I don't keep pictures, but here is the piston from my last top end. This was nearing 200 hours in my Gas gas Ec300. It's as clean a piston as I've ever seen. Only light stains near the rings, no carbon at all. The power valve had carbon on it, nothing unusual. My Lawnboy looked just as good, and that's been going for years running about 1.5 hours per week, every week.

That piston was ran rich hence the results your seeing. Not uncommon at all in 300cc Enduro bikes.
If that bike had been jetted sharp and saw 200 hours of dune riding it would look completely different.

 

[North by Northwest]

I too think it would be strange if R50 has changed. I started using it likely 2016ish. Before that Amsoil dominator was good too, but it was almost twice the price of R50. Today if anything Amsoil is cheaper. Not sure what happened there.

I don't keep pictures, but here is the piston from my last top end. This was nearing 200 hours in my Gas gas Ec300. It's as clean a piston as I've ever seen. Only light stains near the rings, no carbon at all. The power valve had carbon on it, nothing unusual. My Lawnboy looked just as good, and that's been going for years running about 1.5 hours per week, every week.

As Ben has advised , piston wash from a fat tune often will present exactly as your pics show a relatively clean dome & ring set . If you ride hard you will have no issues however usually trail riding with such a fat tune without any continuous load , entails spooge within the muffler & carbon forming within the exhaust port . If all is good within your exhaust port & muffler don't change a thing !

 

[North by Northwest]

I too think it would be strange if R50 has changed. I started using it likely 2016ish. Before that Amsoil dominator was good too, but it was almost twice the price of R50. Today if anything Amsoil is cheaper. Not sure what happened there.

I don't keep pictures, but here is the piston from my last top end. This was nearing 200 hours in my Gas gas Ec300. It's as clean a piston as I've ever seen. Only light stains near the rings, no carbon at all. The power valve had carbon on it, nothing unusual. My Lawnboy looked just as good, and that's been going for years running about 1.5 hours per week, every week.

Yeah I buy Interceptor , Dominator or Saber for under $14 a quart . I see R50 & Benol or Techniplate at more with the exchange rate .

 

[Backyard Lumberjack]

I have no problems with R50.
Benol is only good for door hinges.

i BP and the DIY 50/50 atf and vinegar! keep both in bottles with spl applicator brushes. the BP never evaporates and the DIY never spills! lol. cleaned my ontheroad drill bit set yesterday that got some rain's on them. both systems work well... and for door hinges i prefer reg ol 30-wt engine oil. i save each qt, upsidedown, drains fully, then what is in jar, into spl oil can. workx for me!

 

[jellyroll]

Yeah I buy Interceptor , Dominator or Saber for under $14 a quart . I see R50 & Benol or Techniplate at more with the exchange rate .

amsoil anything is over $22 per quart here.

 

[Backyard Lumberjack]

As Ben has advised , piston wash from a fat tune often will present exactly as your pics show a relatively clean dome & ring set . If you ride hard you will have no issues however usually trail riding with such a fat tune without any continuous load , entails spooge within the muffler & carbon forming within the exhaust port . If all is good within your exhaust port & muffler don't change a thing !

these days i ride my xMark mower, ez. it starts right up, but not easy. i have to set it up, prime it thru the carb, etc. comes to life and not hard on starter. but, piston wash is an issue i want to avoid. so i use saw fuel for the spray in prime. crank it first, to move about oil. i don't like dry starts on an engine....

 

[Backyard Lumberjack]

If I didn't say already, this is 40:1. I had the squish adjusted by taking down the head, and bumped up compression at the same time. 91 octane isn't quite enough. This piston only saw 100LL Avgas.

 

[North by Northwest]

amsoil anything is over $22 per quart here.

Thats retail , preferred customer $9.79 usd for Amsoil 2T Injector/ pre mix oil $12.39 USD for Interceptor Premium Injector & $13.39 USD for Dominator & $13.29 for Saber all 32 oz. Jake .

 

[adedeluca]

Thats retail , preferred customer $9.79 usd for Amsoil 2T Injector/ pre mix oil $12.39 USD for Interceptor Premium Injector & $13.39 USD for Dominator & $13.29 for Saber all 32 oz. Jake .

Used castor for years in our model airplanes . Very good high stress protection BUT they get gummy must clean out periodically .