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Grant31781

2 stroke oil and ratio trail riding

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30 minutes ago, Doc Brown said:

 

Why not use what KTM specifies? 60:1 Crosspower 2T. Done. You can use any other brand provided that it meets the required standards. one point people miss is that the standard alone doesnt tell you all. In case you have a lot of spooge it would not make sense to use an oil with an extra high flash point. Motul 800 has a very high flash point of about 260° C (500 F) and is designed for racers. If you ride lots of technical super slow (first/second gear) stuff and you ride "on the pilot jet" often, its simply the wrong oil. If you race and WOT is used most of the time it is what you probably want.

For all oils you can search the internet for a tech data sheet/technical bulletin to see flash point and other information.

As an example Dominator and Crosspower (be careful to not mix deegrees Celsius and Farenheit ;)

https://www.amsoil.com/lit/databulletins/g1985.pdf

https://www.motorex.com/fileadmin/_pim_product_sheets_/en/Cross_Power_2T_EN.pdf

 

My 2 €-cents 😃

Granted, not on a KTM 2 stroke, on a bike that was in pretty bad shape engine-wise, with so-so jetting.

Slow rider, we mostly do up to 3rd gear stuff. Motorex cross-power 2t, 2%. @16 euro/liter ( I could try to be smart and try to save a bit with questionable oils) it is on the pricey end of the spectrum. I am on the process of doing the top end now and despite the average jetting, the blow by and the general state of the engine, the power valve was spotless.

While any oil with say jaso fd will do, sometimes the little extra in terms of cleanliness helps. The only time I fouled a plug was when I was playing with jetting and I ended up way rich at the bottom.

 

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KLOTZ R50 @ 60:1 in my 2018 KTM 250 XC. R50 is a full syn. and a 50wt. oil .  Manual says 60:1 and MXA magazine did a test running YamaLube 2R @ 40:1 and was having problems with their KTM/Huskys running poorly (rich). They contacted KTM USA and KTM said run them at 60:1 , presto no more problem. If I'm gonna be running my bike @ 60:1 then I want the added protection/peace of mind of a full syn./50wt. oil. Been using the KLOTZ R50 for 15+ years, never a problem.

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3 hours ago, Doc Brown said:

 

Why not use what KTM specifies? 60:1 Crosspower 2T. Done. You can use any other brand provided that it meets the required standards. one point people miss is that the standard alone doesnt tell you all. In case you have a lot of spooge it would not make sense to use an oil with an extra high flash point. Motul 800 has a very high flash point of about 260° C (500 F) and is designed for racers. If you ride lots of technical super slow (first/second gear) stuff and you ride "on the pilot jet" often, its simply the wrong oil. If you race and WOT is used most of the time it is what you probably want.

For all oils you can search the internet for a tech data sheet/technical bulletin to see flash point and other information.

As an example Dominator and Crosspower (be careful to not mix deegrees Celsius and Farenheit ;)

https://www.amsoil.com/lit/databulletins/g1985.pdf

https://www.motorex.com/fileadmin/_pim_product_sheets_/en/Cross_Power_2T_EN.pdf

Motul 710 has a lower flashpoint than Motorex. Only use 800 for high-heat applications (MX, dessert, etc).

Motul 710 2T (data: #1   #2)
Cost: $15.99/liter
Synthetic oil (asumed due to the viscosity index), 10-25% Group 1 oil (CAS 64742-46-7)
viscosity 8.9 mm2/s 100C, 46.4 mm2/s 40C, viscosity index 176, 88ºC flash point
approved rating: JASO FD 

Motorex Power Synt 2T (data: #1  #2)
Cost: $26.10/liter
synthetic group 4 or 5 (unspecified), 25-50% group oil (CAS 64742-47-8)
viscosity 9.1 @ 100C, 50.1 @ 40C, viscosity index 164, flash point 98C, density .87
approved rating: JASO FD

Both are clean and low smoke. Running 60:1 you don't go through much oil anyways so spend the extra money on a decent oil like these. I run Motul 710 simply because I get a 4L jug of it $10 cheaper than the same size Motorex.

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2 hours ago, Hardwrkr13 said:

Motul 710 has a lower flashpoint than Motorex. Only use 800 for high-heat applications (MX, dessert, etc).

Motul 710 2T (data: #1   #2)
Cost: $15.99/liter
Synthetic oil (asumed due to the viscosity index), 10-25% Group 1 oil (CAS 64742-46-7)
viscosity 8.9 mm2/s 100C, 46.4 mm2/s 40C, viscosity index 176, 88ºC flash point
approved rating: JASO FD 

Motorex Power Synt 2T (data: #1  #2)
Cost: $26.10/liter
synthetic group 4 or 5 (unspecified), 25-50% group oil (CAS 64742-47-8)
viscosity 9.1 @ 100C, 50.1 @ 40C, viscosity index 164, flash point 98C, density .87
approved rating: JASO FD

Both are clean and low smoke. Running 60:1 you don't go through much oil anyways so spend the extra money on a decent oil like these. I run Motul 710 simply because I get a 4L jug of it $10 cheaper than the same size Motorex.

Where did you get that flash point # for motorex? Everything I’ve read, says 110 C/230 F. I’ve been running the motorex in my 300xc at 60:1 with great results. I don’t run the engine super hard at all but still I only get a drip or two of sponge out of the silencer tip after a few hours of riding. I may make the switch the bel ray si7 which is the factory recommended husqvarna oil. It has a lower flashpoint and it’s cheaper than the motorex.

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Thanks for the input guys. Nice to see what everyone likes.

As far as a testament to oil directly related to KTM 2 strokes,  Tokyo offroad recently uploaded videos on youtube of his 250XCW  top overhaul at 150hr and 295hrs on the bottom end. He has no bottom end issues and the top end ring gap was barely out of spec.

He has been using the Crosspower 2t at 60:1. Seems KTM got it right to me. This oil is not overly more expensive that any other oil. 

Belray SL2 is the cheapest I found on Rocky Mtn. 50 gallons of premix at 50:1 would cast $25.90 vs Cross power at $57.83. $32 over 50 gallons is not that much of a difference. If the cross power is mixed 60:1 the difference drops to $22.44 

So I think I am going with the cross power at 60:1

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Not to throw the discussion off-topic, but try gas @the equivalent of $7/gallon, this puts everything into perspective! 😃 But hey, its ethanol-free!

 

As much as I don't like boutique products ( I am about to try tractor transmission oil in the gearbox 😂) I will stick with motorex. It seems that they got the formula right.

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Wow $7? Our ethanol free 87 is around $2.50 regular E10 is $2.00.

  Geez  100 low lead avgas is cheaper than $7!

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12 hours ago, Grant31781 said:

So I think I am going with the cross power at 60:1

And I think that's a brilliant idea. Dont want to offend anyone, but using 30:1 when 60:1 is required is a bad idea. More is better, is something that has been proven wrong in the meantime...at least when we talk about two stroke mixtures/oils.

Edited by Doc Brown
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4 hours ago, Grant31781 said:

Thanks for the input guys. Nice to see what everyone likes.

As far as a testament to oil directly related to KTM 2 strokes,  Tokyo offroad recently uploaded videos on youtube of his 250XCW  top overhaul at 150hr and 295hrs on the bottom end. He has no bottom end issues and the top end ring gap was barely out of spec.

He has been using the Crosspower 2t at 60:1. Seems KTM got it right to me. This oil is not overly more expensive that any other oil. 

Belray SL2 is the cheapest I found on Rocky Mtn. 50 gallons of premix at 50:1 would cast $25.90 vs Cross power at $57.83. $32 over 50 gallons is not that much of a difference. If the cross power is mixed 60:1 the difference drops to $22.44 

So I think I am going with the cross power at 60:1

Haha data can be enlightening. 

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Well I am not sure about Amsoil interceptor at 50:1. My ring gap at 94 hours is a shade over 2mm. New rings have a .043mm gap.

I would say the oil didnt do much for the rings! Not sure what would cause this kind of ring wear. 

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A few years ago I replaced a crank seal in a Skidoo with a 462cc liquid cooled 2 stroke engine with 25000 miles or approx. 800 hours on it. It's oil injection system injects oil based on load and varies from 100/1 at low load to 50/1 at full load. The only oil used in it was Shell snowmobile injector oil (non synthetic). The owner had me inspect all internal engine components for wear as 25k miles is quite high for a snowmobile.  All internal components were within spec. and nothing was replaced other than seals and required gaskets. This leads me to believe the ring and piston wear experienced by dirt bikes is probably caused by dirt bypassing filters as apposed to lack of oil. I don't base this assumption on one case as I have rebuilt many snowmobile and motorcycle engines over the years and have always seen more wear on dirt bike engines than anything else.   

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8 hours ago, Grant31781 said:

Well I am not sure about Amsoil interceptor at 50:1. My ring gap at 94 hours is a shade over 2mm. New rings have a .043mm gap.

I would say the oil didnt do much for the rings! Not sure what would cause this kind of ring wear. 

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20190116_175444-2268x2268.jpg

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The piston looks pretty good to me, the ring gap is probably the biggest I ever saw in my life. No clue what this may have caused...

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3 hours ago, Doc Brown said:

The piston looks pretty good to me, the ring gap is probably the biggest I ever saw in my life. No clue what this may have caused...

 Dirt, that’s what caused that dirt. I’ve ran interceptor for a long time it’s really good stuff.

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Quote

 the ring gap is probably the biggest I ever saw in my life.

LOL! My thoughts too! I was surprised it ran as good as it did with those rings. It would crank  1st kick regardless of temperature . It did seem easy to kick. It still had a lot of power. I have no idea how a fresh top end will compare to the old worn one regarding power. I hope to get it back together this weekend.

E-TECH,

I though dirt would cause scratching in the piston and cylinder walls.  The air filter on it was a little dirty but not bad at all. The guy said he changed it when it needed it. The air boots were clean when I pulled the carb and reeds. The bore measurements are in spec. 

 

Maybe he just ran it real hard?

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Be interesting to see the ring thickness measurements for the old vs new rings. 

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I will measure them when I get home.  Do you mean thickness in the up and down plane or the sides that touch the cylinder wall and piston? One is obviously easier to measure.

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47 minutes ago, Grant31781 said:

I will measure them when I get home.  Do you mean thickness in the up and down plane or the sides that touch the cylinder wall and piston? One is obviously easier to measure.

The cylinder wall to piston. Just curious if they actually wore that bad or ring gap was excessive when installed new.

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