Motorcycle Racing Forum

Motorcycle Racing => Wrenching => Topic started by: fed585 on May 27, 2009, 03:51:44 PM

Title: what is gas to oil mix ration on a 89 yamaha ysr 50
Post by: fed585 on May 27, 2009, 03:51:44 PM
i need to know what this is people please help me out
Title: Re: what is gas to oil mix ration on a 89 yamaha ysr 50
Post by: Doctor on May 27, 2009, 05:53:46 PM
I believe those are oil injected.
Title: Re: what is gas to oil mix ration on a 89 yamaha ysr 50
Post by: Super Dave on May 27, 2009, 07:00:57 PM
Quote from: resuscit8u on May 27, 2009, 05:53:46 PM
I believe those are oil injected.
I'm with Jim on that.  Should be a clear reservoir there someplace.  Can't remember if it's under the tail or where.

If it doesn't have it, it has been removed.  Then, I'd start at 32:1.  You could add more and get more power (20:1), but you'd want to increase the jet size to maintain your air:fuel.

You just got it?  How much?  Hopefully a good price.
Title: Re: what is gas to oil mix ration on a 89 yamaha ysr 50
Post by: fed585 on May 27, 2009, 09:35:12 PM
no ive had this thing for ages my dad bought it brand new in 89 and now i have it and i ride it around in the pits at the mid atantic races while he races. but he forget the mixture for it so i posted this thread it is so loud man because he got rid of the stock pipe and but a aftermarket one on along with alot of other things
Title: Re: what is gas to oil mix ration on a 89 yamaha ysr 50
Post by: Noidly1 on May 28, 2009, 11:11:17 PM
Can't go wrong with 32:1. Best all-around ratio. 1/2 cup per gallon.

Sorry Dave but 20:1 will smoke like a sive and kill power.
For best power, run the least oil but, don't expect it to live long...
Title: Re: what is gas to oil mix ration on a 89 yamaha ysr 50
Post by: Super Dave on May 29, 2009, 05:35:00 AM
Quote from: Noidly1 on May 28, 2009, 11:11:17 PM
Sorry Dave but 20:1 will smoke like a sive and kill power.
For best power, run the least oil but, don't expect it to live long...
Best power is actually at around 13:1.  Even Rich Oliver ran 20:1 on his TZ250's when he was beating everyone.  20:1 is generally a really good compromise that doesn't foul plugs as bad.  A two stroke can still run with a 6:1 ratio.  It will struggle, but it will run.  Finally, the only concern IS life of the engine.  Smoke is only a proper byproduct.
Title: Re: what is gas to oil mix ration on a 89 yamaha ysr 50
Post by: Tdub on May 30, 2009, 01:13:46 AM
Quote from: Noidly1 on May 28, 2009, 11:11:17 PM
For best power, run the least oil ...

Pure myth
Title: Re: what is gas to oil mix ration on a 89 yamaha ysr 50
Post by: Woofentino Pugrossi on May 30, 2009, 03:21:39 AM
32:1 is whats recommended for premix in a YSR 50.
Title: Re: what is gas to oil mix ration on a 89 yamaha ysr 50
Post by: Noidly1 on May 30, 2009, 06:42:52 PM
Quote from: Super Dave on May 29, 2009, 05:35:00 AM
Best power is actually at around 13:1.  Even Rich Oliver ran 20:1 on his TZ250's when he was beating everyone.  20:1 is generally a really good compromise that doesn't foul plugs as bad.  A two stroke can still run with a 6:1 ratio.  It will struggle, but it will run.  Finally, the only concern IS life of the engine.  Smoke is only a proper byproduct.


oil doesn't burn as fast as gas, so yes, it will slow you down.
Title: Re: what is gas to oil mix ration on a 89 yamaha ysr 50
Post by: Super Dave on May 30, 2009, 06:52:36 PM
Quote from: Noidly1 on May 30, 2009, 06:42:52 PM
oil doesn't burn as fast as gas, so yes, it will slow you down.
Well, how many btu's does two stroke oil have?

Next, one will have to recognize that as lubrication goes down, friction increases.  I'm not going to make your decision for you, but I will not support your push.  Might be worth looking at yourself and certainly many others used to try going short on the mix ratio but changed.
Title: Re: what is gas to oil mix ration on a 89 yamaha ysr 50
Post by: Noidly1 on May 31, 2009, 10:56:48 PM
BTU's? Heck, I don't know...

While yes lubrisity does go down at higher ratios, there is a sweet spot between wet and slow.

Here's a good Q; What ratio do all of the fast dirt racers use? Bet it's at least 32:1.
Title: Re: what is gas to oil mix ration on a 89 yamaha ysr 50
Post by: Super Dave on May 31, 2009, 11:05:13 PM
Well, they are on four strokes. 

I'm not gonna help you anymore.  You've got your ideas. 
Title: Re: what is gas to oil mix ration on a 89 yamaha ysr 50
Post by: Noidly1 on May 31, 2009, 11:11:37 PM
 :rollseyes:
Title: Re: what is gas to oil mix ration on a 89 yamaha ysr 50
Post by: backMARKr on June 01, 2009, 12:02:08 AM

since when does a sieve smoke?    :err:
Title: Re: what is gas to oil mix ration on a 89 yamaha ysr 50
Post by: fed585 on June 01, 2009, 03:38:26 PM
well im just going to most likely run it with a 32:1 ratio and see how it runs
Title: Re: what is gas to oil mix ration on a 89 yamaha ysr 50
Post by: Tdub on June 01, 2009, 06:31:22 PM
Quote from: Noidly1 on May 31, 2009, 10:56:48 PM


While yes lubrisity does go down at higher ratios, there is a sweet spot between wet and slow.


yes there is and it is right between 16:1 and 24:1  Do your research!
Title: Re: what is gas to oil mix ration on a 89 yamaha ysr 50
Post by: tzracer on June 01, 2009, 09:00:42 PM
Do a search for Gordon Jennings.

Read his articles about oil ratio, you will find more oil is better. More power with more oil. He tried as high as 15:1.
Title: Re: what is gas to oil mix ration on a 89 yamaha ysr 50
Post by: Noidly1 on June 02, 2009, 12:51:51 AM
Good to know... I didn't know you could run so heavy on oil. My bad.
I'm just going by general 2 stroke usage.

BTW, I used to race an 83 RZ350, and when the oil pump went out, I ran 32:1 and had 0 problems. (other than the pump going out...)
Title: Re: what is gas to oil mix ration on a 89 yamaha ysr 50
Post by: benprobst on June 02, 2009, 08:07:29 PM
Quote from: Noidly1 on June 02, 2009, 12:51:51 AM
Good to know... I didn't know you could run so heavy on oil. My bad.
I'm just going by general 2 stroke usage.

BTW, I used to race an 83 RZ350, and when the oil pump went out, I ran 32:1 and had 0 problems. (other than the pump going out...)

So now you admit you were wrong? You would look a lot better if you would have done it 10 posts ago! When will you learn noid, some people you argue with about certain things, others you never argue with about certain things.  :biggrin: Like I dont argue with you on how to work on Yamaha viragos. You dont argue with me on how to ride a motorcycle. And you dont argue with Dave and half of the (informed) world on how to tune a 2 stroke. That or you should go be a factory mechanic over the pond, sounds like you have 2 strokes figured out!!!


:spank:

'sup Noid.  :biggrin:
Title: Re: what is gas to oil mix ration on a 89 yamaha ysr 50
Post by: Noidly1 on June 02, 2009, 11:36:34 PM
Ha Ha Ha. Your funny Benny.  :lmao:

Comming from someone who didn't know what carb sticks were till last week and never heard of S&S carbs, I can at least expect a lot of dumb remarks from you... BTW, that little black thing with the fins on it is called a "rectifier/regulator".  :ass:

I've ran 32:1 in everything 2 stroke I've owned and never had a problem, plus, when I worked at Donelsons, my shop manager recommended that ratio to everyone. So there!
Title: Re: what is gas to oil mix ration on a 89 yamaha ysr 50
Post by: Tdub on June 02, 2009, 11:39:30 PM
You won't have any "problems" at 32:1   But you are not getting max performance at that ratio. So there!
Title: Re: what is gas to oil mix ration on a 89 yamaha ysr 50
Post by: benprobst on June 03, 2009, 09:17:41 AM
Quote from: Noidly1 on June 02, 2009, 11:36:34 PM
Ha Ha Ha. Your funny Benny.  :lmao:

Comming from someone who didn't know what carb sticks were till last week and never heard of S&S carbs, I can at least expect a lot of dumb remarks from you... BTW, that little black thing with the fins on it is called a "rectifier/regulator".  :ass:

I've ran 32:1 in everything 2 stroke I've owned and never had a problem, plus, when I worked at Donelsons, my shop manager recommended that ratio to everyone. So there!

LOL, you're right I dont work on 30 year old motorcycles, I dont work on Harleys, and I dont work on generally shitty motorcycles. And im not sure about the rectifier comment, but I assure you I do know what it is. Something you may want to consider, is just because people ask you questions, doesnt mean they dont know what the fuck they are talking about, its a tool to let jabber mouths talk. And you wouldnt beleive what you can learn from someone when they think they are enlightening you, all you have to do is sit back and listen. And im not talking about mechanical knowledge, more about character. However, motors and motorcycles that I have built have accumulated about 115 wins in the past 4 seasons. 6 regional championships, and a handful of national runner ups, I also get paid thousands of dollars to build motorcycles for people from across the country (as opossed to your, what 11 bucks to work on Viragos) so youre right I dont know a god damn thing, and you are the all knowing master yamaha tech. However with all of that set aside, one thing I dont do that seems to be one of your past times is argue and give advice on shit that you really dont know anything about. Its like me coming into Jerry's shop and telling you how to set timing on a 1970 suzuki, or telling you how to use your carb stick. It just doesnt work that way, similar to you trying to tell me how to gear my motorcycle, or trying to tell Dave he is wrong and doesnt know how to tune a 2 stroke. Or some of your dyno advice ive heard spewed about. Your a good guy Dion, a good motorcycle mechanic, and I like you, just sometimes I think its important to remember your place. Im sure ive stepped out of mine a few times, but I try hard not to, especially when dealing with people significantly smarter, faster, or more experienced than myself.