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Anyone running 40:1 in your 125

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Everywhere I look people are saying 32:1 no matter what, I have a 02 ktm300exc that I run 40:1 with motul 800 synthetic and I really don't wanna buy a new gas jug or mix two. The other bikes a 01 yz125.

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I'm running 40:1 in my 2011 yz 125. Runs great, I experience a little oil build up at the end of my silencer from time. Have never fouled a plug

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I am running 40:1 with Motul 800 Offroad Racing. Started with 33:1 and 30:1 and discovered that there was some oil/carbon buildup in the exhaust and had a fair amount of spooge coming out after every ride. Note that at the time I was completely new to dirtbikes and didn't really know better. After talking to a few MX people, I decided to try 40:1. The difference is apparent, but not really significant. I am quite sure that using this oil (the 800), a 2.5% premix is well enough for me. Mind, though, that I am an amateur rider, have never been to a proper MX track and have until now only ridden trails or small backyard single-line tracks. So obviously I don't push the bike a lot and even when I do, I don't have the stamina to do it for several laps.

What I also learned from researching 2 stroke oils is that the Motul 800 has a substantially high flash point. Which means it doesn't really burn well if you don't go fast (compared to other oils, for example). So perhaps it's better suited to intermediate and better riders.

Motul 800 ... 525F/274C
Amsoil Dominator ... 201F/91C
Yamalube 2-R 255F/124C

Edited by Narciss
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Im not on 125 bit on 250, but I run 40:1 motul 800 on the track and im always in the powerband, not overreving like a 125 but always hard on the engine and after 40hrs, my piston still look pretty good. No carbon buildup. I change my plug after 10hrs always for precaution. 40:1 is a very good mix with motul, and if you do trail riding and your not that hard on the engine, you can run it at 50:1 without any issue for sure. My local shop owner told me that when he race back in the days, he run is rm250 at 60:1 with motul 800 with know probleme. That a little bit too dry im thinking. run it at 40:1 and dont worry about it.

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You shouldn't have a problem running Motul 800 at 40:1 on a 125. As Narciss pointed out it's a very high flash point oil and unless you're really badass and can hammer out a full throttle, pipe bluing, 40 min. moto at Glen Helen you won't have any problems on the protection side of things. You're more likely to have spooge, loading up and plug fouling problems, especially if you're just a trail rider.

As a matter of fact, I know some KTM trail riders running this stuff at 60:1 without any problems other than spooge.

Edited by 218

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Thank you guys for your help looks like I will use the same gas for both bikes

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I always mixed at 40:1 and never had a problem with the '04 YZ125 or any of my other 2-strokes.  The only change I made for my 2-strokes is started to use VP T2 cause I wanted to get away from the ethanol mix, and the VP comes premixed at 40:1.

 

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My son rides a 02 yz125 in the woods mostly single track. And we run it at 40:1. with H1R. I mix 3 gal. of 100% 93 pump gas with 1 gal 110 race gas. And it seems to do just fine. We are also running an #8 plug in it. It is all stock with the head cut and a flywheel weight. Fun bike.

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21 hours ago, nopo530 said:

Everywhere I look people are saying 32:1 no matter what, I have a 02 ktm300exc that I run 40:1 with motul 800 synthetic and I really don't wanna buy a new gas jug or mix two. The other bikes a 01 yz125.

Virtually no difference between 32 and 40 : 1.  If it really bothers you enough to troll the Yamaha threads (with your orange problem  :(), run 36:1 in your "community" gas tank.

As Hillary says, "What difference, at this point, does it make?" 

Please do not ask which oil is best :rolleyes:

HaHa, hope that works for you.

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:thumbsup:  Only in America do we have such problems   

 

You could run both at 32:1 or 40:1, just keep in mind that less oil = more gas, which means you're running a tad richer. 

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If you look at a 2 stroke premix

chart, the difference of 40:1

(500ml) vs 32:1 (626ml)

in 20 litres, or 5 gallons, is only

126ml different.  Divide 20 litres

down to litres

( 126ml / 20 = 6.3ml per litre

difference )

Not much. 

 

 

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I run 125 ml to 4.5 litres which works out at 36:1. I just do this because its convenient as Motul 800 comes in 1 litre bottles... so i get 8 fills exactly to a litre of oil

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I'm not really sure how much a difference it makes but on my 125 getting the snot revved out of it over an entire season I have to assume there is less wear over time with 32:1. I never have spooge either so I see no need to run less oil.

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I have been getting the pints of yamalube and dumping into the jug w 4 gallons of fuel.

I carefully measure out a 3:1 ratio of 93/ Sunoco110.

No spooge and the bike is crisp.

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I am running 40:1 with Motul 800 Offroad Racing. Started with 33:1 and 30:1 and discovered that there was some oil/carbon buildup in the exhaust and had a fair amount of spooge coming out after every ride. Note that at the time I was completely new to dirtbikes and didn't really know better. After talking to a few MX people, I decided to try 40:1. The difference is apparent, but not really significant. I am quite sure that using this oil (the 800), a 2.5% premix is well enough for me. Mind, though, that I am an amateur rider, have never been to a proper MX track and have until now only ridden trails or small backyard single-line tracks. So obviously I don't push the bike a lot and even when I do, I don't have the stamina to do it for several laps.
What I also learned from researching 2 stroke oils is that the Motul 800 has a substantially high flash point. Which means it doesn't really burn well if you don't go fast (compared to other oils, for example). So perhaps it's better suited to intermediate and better riders.
Motul 800 ... 525F/274C
Amsoil Dominator ... 201F/91C
Yamalube 2-R 255F/124C

This is why I'm switching to 710 low flash point if I rode track more I'd keep the 800 but I just can't burn it and I'm already pretty lean on the jets

IMG_1492817469.206433.jpg
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