Old Polaris gas mixture

[softballfisherguy]

I've got a couple old Polaris sleds (early 70's). In the manuals for them it says the gas mixture should be 20:1 or 40:1. Now my question is - the ratio for these two mixtures is quite a big difference. Why the big variance and discrepency? Any thoughts to which one should be used?

[PierBridge]

I'm running 50-1 in my old poo poo's.

I think the oils are better now a days and you would be fine running 40-1.....

[Sergeant Slabber]

I would say that it has alot to do with how hard you're going to be running the sled. If you're just going out for an easy joy ride for an hour or two, I would say 40:1. If you are going out to race and give the thing heck, go 20:1

[fisherking01]

They'll smoke like crazy with a 20:1. With todays oils and gasolines, there is no need to go that rich. I have friends that race "vintage" snowmobiles 70's and some late 60's. they run 50;1 , but their sleds are very well maintained (jetted clutched for temps)

In the 80's we ran 50:1 in our 70's model TX 250, and 340 with no problems.

You would be safe running the 40:1 mixture. Any richer than that you will foul plugs and smoke like crazy. If you feel uncomfortable going to 50:1, start out at 40:1 and see how it works. Sparkplugs should be burning a light brown to tan, not oily black. Hope this makes sense, Brent

[softballfisherguy]

Thanks for the replies. I'm a little late in checking back - but now that the snow is pretty much gone it had kind of been in set in the back of my mind. It was pretty much the kids riding them around the yard - pulling sleds - not hard riding, but you are correct - at the 20:1 you can see it coming with the smoke that is for sure. Thanks again.