best oil to mix with race fuel?

[GO OVRIT]

I tried amsoil dominator when I first started out, but it seemed to leave a lot of crud in the bottom end.  I see less with the Klotz super techniplate .  There's plenty of film left on everything with both.  I run 110 at a ratio between 32 and 40 just because it fills my mixing bottle for 5 gallons.

[pinned250r]

I run 40:1 strictly because 1/2 a quart equals 5 gallons. Easy enough

[Tbone07]

Maxima Castor 927 @32:1. I started using it in my CR250 and had nothing but great luck, so I stuck with it.

A lot of oils will work good for you and others. Whatever you do.....DO NOT run 50:1 like some of the bottles say. You're only asking for trouble

[rablack21]

I run 40:1 strictly because 1/2 a quart equals 5 gallons. Easy enough

I'm with Pinned. I used to run Amsoil Dominator at 50:1 with zero issues, but eventually changed to 40:1 for convenience. No more carrying around a measuring cup and an extra bottle. It's just easier to mix 1/2 a quart to my 5 gallon fuel can.

[pinned250r]

Hey I've heard of guys running 100:1 with no problems, I guess I'm not that risky though.

Although a side note, I did just take my top end off to play with the squish a little and found Amsoil all over everything in my cylinder. Never had that before with it.

[rablack21]

Hey I've heard of guys running 100:1 with no problems, I guess I'm not that risky though.

Although a side note, I did just take my top end off to play with the squish a little and found Amsoil all over everything in my cylinder. Never had that before with it.

There's always been alot of debate over oil mix ratios. However, pretty much all the manufacturers still making 2 strokes (dirtbikes) recommend from 50:1 to 60:1. Not always, but in most cases manufacturers don't typically do something that they aren't completely comfortable with and have tested thoroughly. And there has really not been much of a change in technology either. And consider this, if you take 250r's out of the equation, look at other applications: chain saws, sea doo's, marine 2 strokes, 2 stroke street bikes. Pretty much all of them run atleast 50:1 all the way up to 100:1.

[havinnoj]

Klotz R-50 @ 40:1. 1 pint to 5 gallons.

[broken1]

I'll probably be looked down upon for saying this because I've never seen this brand mentioned but I've been running torco gp7 & rocket or VP 110 at 36:1 in my R for the last 23 years with no issues. Every time I've had the top end off it looks really good inside.

[udontknowme]

There's always been alot of debate over oil mix ratios. However, pretty much all the manufacturers still making 2 strokes (dirtbikes) recommend from 50:1 to 60:1. Not always, but in most cases manufacturers don't typically do something that they aren't completely comfortable with and have tested thoroughly. And there has really not been much of a change in technology either. And consider this, if you take 250r's out of the equation, look at other applications: chain saws, sea doo's, marine 2 strokes, 2 stroke street bikes. Pretty much all of them run atleast 50:1 all the way up to 100:1.

the debates and pissing matches are only between all the nobodys on all the internet sites.  the top dog tuners ive talked with have no debates. use alot of oil is what theyve said. this applies to engines of the highest performance however. i believe even jerry has the same thoughts on this if i recall correctly, since this subject has already been hashed out here before (as well as every other site 1000 times) and i do believe he posted his thoughts on this.  engines of low to moderate tune should do fine on lesser amounts of oil 32-40-50:1 etc . i say 'should' because ive seen several averagely riden moderatly powered bikes go quit a number of years on original crankshafts and pistons with these lesser qauntities of oil, but like i said theyre moderatly powered and averagely riden.  now if youve got a 65hp 250 spinning up 11k rpm you may want to throw a big pile of oil at it, atleast i would anyways

the 50 and 60:1 thing from ktm i think has more to do with emissions than anything. and of course to look good in the eyes of the epa or who ever it is that watches over that stuff. not that ktm is governed by any emission rules on their offroad stuff but why not put on your best suit and tie to give the world the impression your doing the right thing, if you know what i meen.

i have no clue about weedwakers (mines electric) but i have to think emissions is a big deal in that market as well.

so when joe blow the trail rider toots his horn he gets 5 or 10yrs from every crankshaft on 40:1 i have no problem believing that but if youve got +30hp and +3k rpm more than the engine was originally intended to have, you may want to consider a extra pinch of oil, or not and see your rod bearing or piston go up in smoke

[Jerry Hall]

I still do consulting work for a hand full of two stroke engine companies that build engines for different applications.  Emissions has never been one of the companies design requirements for the  engines that are used on the aircraft drones and paragilders.  Their main goals are they have to be lightweight, high power and they ALWAYS have to bring you home or have to bring all of the expensive top secret stuff on board home.

 
Emissions plays a huge role in the total design of the engine that are used for leaf blowers, string trimmers, hedge trimmers, etc.  We are constantly having to meet new emission requirements.  Finding an oil that will meet the lubrication requirements for these engines is not much of a problem, but the oil must burn clean and not plug up the exhaust port, muffler or catalytic converters.  Just about any high quality outboard motor oil or synthetic two stoke oil at 40:1 to 50:1 will satisfy these criteria.

[chadlwa]

Anyone else use Dumonde Tech, thats what the local shop by me carries.

[the cosmic avenger]

Maxima 927 for me 40:1 in 110 for me.  Will run this oil with non ethanol pump premium/a little race gas in the new ktm 250 I bought as well.  If you have ever torn an engine down with synthetic ran in it and the ones I have seen are dry as a bone no oil coating on any part I don't like that

I don't know what oil you are running or what the mix ratio is but I can tell you I personally have at least 25 or more engines running around on synthetic with no issues. I've had motors go 5000+ miles running synthetic.
 Ams is ok. I still have some in the garage but there for a cheaper more accessible options out there.
Especially for 10w-40 bike oil.

[havinnoj]

Anyone else use Dumonde Tech, thats what the local shop by me carries.

I've ran it a few times over the years as that's what Arlan recommends.  Never had any issues with the premix (or tranny oil for that matter).  Always ran fine in my R's.  I use R50 because it's easier to get a hold of and smells nice!

[nathan89]

Surprised no one runs Maxima Super M. Works great in my woods bike. Never fouls plugs and burns clean. Leaves a very nice oil film inside the motor too. I mix at 32:1

[jfwyatt1]

ive been using semi synth. lucas for the last bit with good results in my cr250 and the R the local lucas rep gave me a case to try. when my son called me a few weeks back when he cold seized it before i found out what had happened i was thinking it was due to the lucas but after he finally admitted he hadnt let it warm up before hammering it and that he didnt even clear the end of the driveway when it locked up. im still hesitant to go full synth. even with motor oil due to having problems in the past (years ago) and i know its probably silly of me to be that way. but all 3 times i have had bad engine blowups i was using full synth. never had trouble with dino or semi. so ill stick with those type oils for now.