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Boy, does the gas mixture make a difference

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Being that I'm going riding tomorrow for the 1st time on my KX, and for the 1st time since 1973. I have been getting the 250 as ready as possible, and being that the previous owner mixed Spectro synth at 32-1...:lol: I spued oil / gas out of the pipe, and smoked like crazy..so after draining the old gas yesterday, and puttin new gas with Golden Spectro at 52-1, and raising the clip up to the 2nd from the top, it runs way stronger, starts on the 1st kick evrytime. Got all my gear, gassed up and ready to go.

I'll be headin up to Rowher here in so. cali. I'm debating on whether to take the dig. camera or not..if I do, I'll post some pic's...Dang, I'm excited..:applause:

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Remember that the main, rod and crank bearings are lubed by the oil in the gas. The oil you add to th motor is just for the tranny. The entire bottom end rotating assembly as is the cylinder is completly dry unlike your thumper.

The whole motor is lubed by the oil in the gas. Less oil means less lube. Even if the lube is the greatest on earth it takes a certian volume to coat the bearings.

Smoke out the tail pipe is not a bad thing. Changing mixture for smoke amount ot power means you are swapping those things for less engine life.

I do not have a problem with that mind you, I'd do the same I am just saying many do not realize the motor is dry. Less oil is less lube.

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Thanks..and I realize that the oil in the gas lubes the top end, and I use to race 2 strokes in the early 70's, dirt tracking. Maybe I should have mentioned that the lowest ratio Golden Sprectro recomends is 42-1..and as high as 64-1..so I think I'm safe at 52-1. But just to make sure, I'll take a plug reading early on.

As a side note..when I raced, we use to mix Blenzall at 50-1 when they recomended no higher than 40-1, but it was all in quest for more power. I raced about 3 times a week, and had to rebild the top end about once every 2 weeks..lol, but I worked for Yamaha at the time, so parts were cheap, cost me all of 30.00 including a bore job..

Remember that the main, rod and crank bearings are lubed by the oil in the gas. The oil you add to th motor is just for the tranny. The entire bottom end rotating assembly as is the cylinder is completly dry unlike your thumper.

The whole motor is lubed by the oil in the gas. Less oil means less lube. Even if the lube is the greatest on earth it takes a certian volume to coat the bearings.

Smoke out the tail pipe is not a bad thing. Changing mixture for smoke amount ot power means you are swapping those things for less engine life.

I do not have a problem with that mind you, I'd do the same I am just saying many do not realize the motor is dry. Less oil is less lube.

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Oh I agree with you, 2 stroke bikes are way cheap. I run 40 to 1 myself.

I was mentioning it for others who do not realize this not so much for you brotha. I was picturing 20 year olds with no mechanical knowlege running 70 to 1 since less oil is clearly better. They read it on the internet.:lol:

I wanted people who read who do no tknow to understand what they are getting or risking.

I know you the man. It was not directed at you brotha.:applause:

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Oh I agree with you, 2 stroke bikes are way cheap. I run 40 to 1 myself.

I was mentioning it for others who do not realize this not so much for you brotha. I was picturing 20 year olds with no mechanical knowlege running 70 to 1 since less oil is clearly better. They read it on the internet.:lol:

I wanted people who read who do no tknow to understand what they are getting or risking.

I know you the man. It was not directed at you brotha.:applause:

Ahh, gotcha...always thinking ahead, unlike me...:eek:

Just a note: Amsoil has a 2 stoke oil that can be mixed at 100-1, I've read that guys have done that with out any problems...so maybe it's the oil that dictates the mixing ratio..?:lol:

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Smoking and spugeing mostly comes from fat jetting not to much oil in the gas. I know some oils like to be run at different ratios but I like to run 32 or 40 for everything. Anyway IMO find a mix you like stick to it and jet to it. Ed

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Boy howdy! does it ever make a differance. I have used golden spectro for 25 years and just switched to AMSOIL Inteceptor , what a difference ! the AMSOIL is much cleaner burning oil, I run from 40:1 to 50:1 depending on temps.

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I remember back in the early 70's we used to run 20 to1 oil/gas mixture. Lots of bikes had aluminum or steel sleeve cyclinders. With the advent of chrome liners, ratios went to 32-1 or 40-1. Beyond that, I don't trust that the new oils are that much better at lubricating the bearings.

I run 40 to 1. Change spark plugs once a year and haven't lost a bottom end.

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Will, what kinda bike di you have back then..? I raced Yamaha's, cuzz I worked form them, and got parts really cheap..

Remember the ole Bean oil..? :applause:

On a side note: after my ride yesterday, I checked the plug, looks way better than before, but still a tad rich, as in it's not dripping oil, but balck. So I went to my local Kaw race shop, and picked up some jets 48-50 slow jet, and a 155 main. When I pulled the slow jet out it was a 45..that's why it ran so clean down low..lol I then replaced the 160 with a 155. While I had everything apart, I cleaned and tightened all fasteners ect. So, I'm about to make a run to see how she fairs in the jetting dept..

Sucess...plug looks very good, bike pulls hard, except for a bit of clutch slippage, time for a new clutch, my guess is it's the orignal one.

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I usually run 33:1. On fast rides where I expect high RPM’s for long periods I mix “fatter” (up to 25:1 ).

The bike runs clean and does not foul plugs. The power valve has never gotten stuck.

There is a little “spooge” but some WD40 and two minutes of work will take care of that.

I did blow up the engine in my old KX250. I believe the reason was lack of lubrication. I was running 33:1 at the time (high rpm’s on fire roads = less oil in crankcase).

Personally I would never mix less than 33:1.

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Ipone semi-synthetic. My ’05 husqvarna WR 250 is dual-sported and is sometimes used for long rides where fast fire-roads are included (high rpm’s). I did use yamalube semi-synthetic for the Kawasaki.

Please keep in mind I am not an expert, but I do not believe that the fully-synthetic oils should be mixed any “leaner”. If there is sufficient oil in the engine it gets lubricated. Any quality 2-stroke oil will do the job. Maybe the crankshaft bearings and piston/rings will last a bit longer with fully-synthetic oils BUT I suspect that there is more danger of internal rust in the engine when fully-synthetic oil is used (I have heard and read this).

This internal rust issue is to me a big deal in any 2-stroke dirt bike. I sure have seen some rust spots on the crankshafts of my bikes when I do rebuilds. Obviously a pitted crankshaft bearing will not last a long time.

I don’t think I ever did wear out the bearings in my wheels or suspension links. The same goes for my steering head bearings. They all get penetrated by water in a year or two and rust, unlike the bearings in my cars and street bikes. Those will last for years, but then they are not heavily exposed to water and dirt.

So the danger of the crankshaft bearings getting pitted by rust and failing shortly afterwards is very real to me. That’s why I stick to semi-sythetic.

But then I may be wrong :-) If someone knows better, please enlighten us.…

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