Oil Gas Ratio?

chadg

chadg

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Age
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Location
redford, mi
Would anyone happen to know the Oil Gas ratio for a 1974 Moto SKi 440 Grand Sport. I know she is old but she only has 586 Miles. After I clean her up I will get some pics, it is nice for a 74. Was garage kept. I think it is 50:1 but I would hate to ruin it by Guessin. Thanks alot guys
 

Thanks but do you think a little leaner would be ok on the old goat. Well I guess that may be better than smokin out the hole niehborhood lol.
 
I would also go with the 50:1 mixture for the trail sleds and a 32:1 for the more performace minded sleds. Brad
 
thanks guys i think i will try 50:1 first because i would hate to have to lean of a mixture.. and then i would like to try a 40:1 later and see if she runs as good. Either way I think i am relativly save with either or. I really appreciate all the feedback. That is what Totallyamaha.com is all about. friends helpin friends. Hope to see you all on the trail one day. And by the way I would like one of the Stickers Mr Sled has Available if they stilll are.



Go LIONS :offtopic:
 
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50:1 is a leaner mixture than 40:1, 50:1 is too lean for an older sled, especially if you plan to do some seious running. 40:1 with a good synthetic oil is a safe starting place
 
I used to run 50:1 with a good synthetic. 40:1 is probably a better choice for an older sled and it wouldnt be so rich that you would notice a smoking problem.
 
thanks sno i Will run 40:1 first i was just not sure wich was lean and wich was rich. That does make sense. Question if I run richer will i go throu plugs a lot faster? And if a machine is running rich is that bad for the pistons? Thank you very much
 
chadg said:
thanks sno i Will run 40:1 first i was just not sure wich was lean and wich was rich. That does make sense. Question if I run richer will i go throu plugs a lot faster? And if a machine is running rich is that bad for the pistons? Thank you very much
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you may notice a descrease in plug life if your carbs arent jetted well. also the correct heat range plug will go a long way to keeping the plugs clean. i run 20:1 in most all of my machines dont have any problems with plug fouling becuase there all jetted well. what most people dont know is engine wear is reduced and power increases the more oil you use down to about 12:1 will you notice the extra power and reduced wear on a trail sled probably not but dyno a high HP/cc engine and it will become clear. more oil is better. let the ranting and skeptisism begin.
 
It is always better to run richer than leaner. In my race sleds, I run 20:1 with a good synthetic, and I have no fouling problems. And yes, jetting is very important, but if it runs well, don't mess with it. For plugs, a hotter plug will, of course, foul less, but will also burn hotter. With NGK plugs, a 9 is usually a good trail plug.
 
I think i am running a 7 in it now or at least that is what was in it when I bought it. As for the mix ratio I guess I will try 30:1 first. I started it the other day to see if the lights were workin and it ran ok. I know that it is warm out but It looked llike oil was seeping through the turns in the exhuast pipe like it is blowin gas or somthin. I need to drain the fuel and probly clean the carb. The only thing is, is that I am not sure if I can get parts for this if I get to deep. 1974 motoski grand sport 440
 
I would probably run a colder plug, a 7 is pretty hot. With NGK plugs, the higher the number, the colder the plug, 6 being hot, 10 being cold. If you ever need parts, look with Royal Distributing. They have lots of parts for the older sleds.
 
Cool thank you I think I will take the carb out today and clean it drain the gas tank out as well. do you think if i run the br9es same as my vmax she will be alright? I just know the gaps are diffrent, and i have no manual for this sled. thanks
 
Mission complete carbs clean. I know it only has 586 miles on it but these carbs were clean as hell. did not have to do much. MADE A MISTAKE I SAID THE PLUGS IN THE MACHINE WERE A 7 THEY ARE AN 8 BR8E. One of the gas tubes keeps slipin off the gas tank inserts. The hoses are pretty hard I will just get new ones. Thats cool monty I am sure it is fun to ride it. I think i will have fun with this one lol.
 
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