Question on 2 stroke oil ratio

[zoom426f]

I just purchased a 01 yz 80 that has been stroked and bored to a 105 for my son. The guy I bought it from said I need to run vp 107 fuel. He also recomended I use PJ1 synthetic. The bike only has maybee a 1/4 tank ran through it using the race fuel and synthetic oil. I live in a small town, cant find JP1 so I opted for bell ray mc-1 synthetic. I noticed on there info they recomend using a ratio of 50:1 for the best performance.
1. Would any of you run this oil at that ratio?
2. Would you use a synthetic to continue the breakin?
3. Would I hurt the engine if I mixed the vp 107 oct. with pump gas of 92 (it would average out at 99.5 oct.)
Thanks for takeing the time to help a rookie
:ugg:

 

[Jaybird]

If you can find an AUtoZOne or similar store, try Mobil MX2T. It is very well priced and a quality oil.
I wouldn't change oils after break-in, just pick one and stick with it.
I happen to feel that with small bore engines it's much nicer to run a ratio at 26-32:1 Those lil screamers need lots of oil. Once you decide on a ratio, stick with it also. Once you get the jetting straightened out you can decide if you want to tweek your ratio, but I'd use more oil than 50:1. Remember...a lil spooge never hurt anything.

Mixing your fuel wont hurt a thing. Just remeber that pump fuel is not very consistant. I would tend to heed the advise of the builder on the higher octane, but you can experiment and see what works for the bike.

 

[Buzz Bomb]

I don't think changing oils after break-in would pose any problem. I would however agree that Mobil MX2T is a great oil. Any high quality oil will work just fine, but mix it at at least 32:1 in that bike. 50:1 is way too little oil for an 80 if you ask me. I wouldn't even run that ratio in my 250.

 

[yardpro]

i concurr on the 32:1 (4oz /gallon) ratio. It won'd affect performance, as amatter of fact dupont did research and found Hp increased until ~16:1, and was only affected then b/c of plug fouling. Also if you can't find vp fuel locally, try aviation fuel. it is ~105 octane. the specific gravity is a little different, but it would be a viable substitute.

 

[wrench]

Play it safe and go with the builder's suggestion. As for the oil ... I am partial to the MOTUL 600 with Amoco premium (50:1). EGORR did some work to the cylinder head (for the woods) on my YZ 250 and recommended the pump fuel .... Motul recommends 50:1 ratio. My jetting is spot on, after roughly 160hrs. on the top/bottom it is still running well.

As for your situation .... if you cannot find the VP and need to use pump fuel bear in mind that it may run a little bit leaner (race fuels tend to run slightly richer). So you may want to try 44:1 or 40:1.

But if you like to play around like Rich Rohrich you can have hours and hours of fun mixing up stuff that burns and changing the jetting around. If I remember correctly he runs 16:1 in his two strokes.

Hope this helps.

wrench

 

[Jaybird]

Also if you can't find vp fuel locally, try aviation fuel. it is ~105 octane. the specific gravity is a little different, but it would be a viable substitute.

I have experimented for quite awhile with avgas and it is definately more consistant than any pump gas I've found, but if you are into the perfomance aspects of the bike, stay away from avgas. Although the octane level is higher than pump fuel in most av fuels, you'll find it robs throttle response. I've only used 100LL avgas, I'm not up on any 105 octane stuff.
If you can afford to keep buying the VP fuel, do it. Remember that whatever you use, you need to jet accordingly. Changing fuel or oil will probably mean you need to also change jetting again.

 

[01Yama125]

We have the same bike. Man the Yama 105 is strong. We run 32:1. That is what our manufacturer reccomended. I find it hard to believe a true works engine builder would reccomend anything above it. We use Red Line, but it was difficult to find. We wouldn't hesitate to use Motul 800 if in a pinch.

On the gas issue. The better engine builders will design an engine for the type of gas you plan on using. So the type of gas you use will definately affect performance. For example, our engine will not run well on Sunoco 110. But it is everywhere in my area. Find out who did your engine. Since it was stroked it will most likely be a major builder. Call him he will give you specific advice you will not recieve on this forum.

 

[zoom426f]

A big Help

Thank you one and all for the advice you have givin on this subject. One thing that no one commented on was if they liked the Bell-Ray MC-1 two stroke oil. My locall dealer says its great, any opinion?

Thanks Again

 

[Rich Rohrich]

Re: A big Help

Originally posted by zoom426f
no one commented on was if they liked the Bell-Ray MC-1 two stroke oil. My locall dealer says its great, any opinion?

MC-1 never had that great a reputation and has certainly fallen out of favor with everyone but the guys who sell BelRay. There are so many readily available high quality low cost synthetics that it should be easy to find a superior product. PJ1 is a good product and can be ordered in bulk from companies like MX-South. There are a million "opinions" about oil ratios but there is at least some scientific evidence to support using more oil rather than less from a performance standpoint. It's your call.

I'm not familiar with any fuel from VP that is 107 octane. You might want to get some specific information on what was being run in the bike.

 

[Rich Rohrich]

Originally posted by 01Yama125
Call him he will give you specific advice you will not recieve on this forum.

Don't bet on that!
It's obvious you haven't been around here very long.:D

 

[cp380sx]

Rich, Bel-Ray MC-1 has been around a long time and I've never heard a bad word about it. What in particular are you referring to about it? I am currently running it in my bike and it seems to be fine. I've run just about every oil at one time or another and I've found that they all do a pretty good job. I've owned 33 MX bikes in the past 30 years and I have never had a seized rod or crank bearing.

 

[bwalker]

I put a top end on a cr 250 for a friend of mine that ran nothing but MC1. IMHO mc1 left a lot of deposits on the piston crown, head and the top ring groove compared to some of the other oils I have seen. The exhaust valve did not appear to be that bad.

 

[cp380sx]

Jetting and fuel quality have more to do with deposits than premix. IMHO

 

[IBWFO]

I've had great results with PJ1, but now use/prefer Motul 100% synthetic.
I run it in my 02 CR 125 and 250 along with MR2 mixed 60:1.
I have re-jetted both bikes and have put a ring in the 125 and everything looks great.
I ran Bel-Ray back in the late 80's and had an RM 125 sieze, since then I have stayed away from Bel-Ray.
If you live in a small town you might want to order your oil through the magazines. Good prices and you don't pay sales tax.
Best of luck.

 

[bwalker]

Jetting and fuel quality have more to do with deposits than premix. IMHO

I agree. The bike I mentioned however was ran on vp c12 fuel and was well jetted.

 

[Rich Rohrich]

cp380sx - If you're happy with MC-1 then by all means use it. The experience I've had with it convinced me there are better choices, and would keep me from ever recommending it to anyone for race engine use. FYI , 30 years of oil related research would strongly disagree with your thoughts on oil's influence in terms of combustion chamber deposits, but you're certainly entitled to your opinion.

 

[cp380sx]

Rich, you still didn't answer my question as to what problems you've encountered with MC-1. I'm not married to MC-1 by any means.

I have had very top end failures of any kind so I think too much enphasis is given to this subject. The last time I had issues with deposits was 30 years ago when we ran castor bean oils. They smelled great but really gummed up the works. Modern oils are all pretty clean in comparison.

 

[JohnScott]

I started out with MC-1 - paying $5 for 12.8oz at the dealer. I have since discovered Mobil MX2T for $3.50 for 160z at Autozone. My dealer is never on my way to anywhere while Autozone is (they're open late and on Sundays too). Plus, I think the Mobile is a better oil - just my gut feeling...

 

[cp380sx]

The Autozone MX2T is a great deal @ $3.50/pint. I have bought a few pints of it as I am nearing the bottom of 1 gallon jug of MC-1. Very convient and a good value to boot.

 

[IBWFO]

Rich,

Have you heard of this new product KLOTZ has come out with that is an additive. They claim that you add 1 gallon of this stuff to 4 gal of 93 oct pump gas and it produces some unbelievable results. It says on the back of the container, to go up 2 jet sizes and also advance your timing 2-3 degrees.
I have a buddy that bought some (he didn't want anyone to know) and he thinks he is going to hit the track Sunday and blow everyone away.
It also indicates on the back of the container that it will add oxygen to the fuel? COXCO is what the say is in it. Also says it adds 37% oxygen to the mixture. At $49.95 I will stick with MR2


D

 

[cp380sx]

Here's the Klotz sales pitch:

Klotz COXOC Gasoline Power Additive is one of the most effective and powerful means of increasing horsepower without extensive engine modifications. COXOC carries an additional 37% pure oxygen into the fuel mixture which improves the combustion process by enhancing stratametric efficiency. Increased combustion efficiency allows more gasoline to be burned on each power stroke. This improvement will yield power increases of up to 6% across the engines power band without spikes or instability. COXOC is equally effective in 2 and 4 stroke engines

Your buddy would probably be better off spending his money practicing out at Mosier Valley tuesday and thursday.

 

[IBWFO]

Agreed. His dad has always sent his engines to either Pro Circuit or Tom Morgan, and they usually are fast bikes, but he can't ride. He always crashes (and hard), so when I found out that his dad bought some of this stuff the shop owner said to keep it quiet because his dad didn't want anyone to know!
Guess if I see his kid doing quads Sunday at Oak Hill I'll have to think twice.
You racing this weekend?

D

 

[Rich Rohrich]

Originally posted by IBWFO
Rich,
Have you heard of this new product KLOTZ has come out with that is an additive.

I've been playing with it this summer in my CR125 and have found MTBE based fuels like Phillips B35 and VP MR2 easier to tune and easier to get crisp throttlle response with. No dyno results but short acceleration tests seem to favor MTBE based fuels. I didn't approach this testing in a seriously analytical way , so it may just be a rider perception issue. Either way I won't be buying it again.

 

[nephron]

COXOC carries an additional 37% pure oxygen into the fuel mixture

Wow!!! Superdedillideeewowww!!!!:)
37% pp02 increment from an additive!! Wow!!! Better than a Roots & 20# boost, better than twin turbos, better than 3 stages of nitrous!!! Where do I get it?!! Oh please, me first!!!

...sound like a bunch of coxocsuckers to me.:silly:

 

[Rich Rohrich]

Originally posted by cp380sx
Rich, you still didn't answer my question as to what problems you've encountered with MC-1.

Rust on critical engine parts, crank lower end life that was shorter (based on number of drag strip passes), odd wear on steel sleeve air cooled bores were just part of the fun I've encountered with MC-1 regardless of the ratio used. I'm thrilled that you've had more positive results. As for me if someone dropped 10 free cases of MC-1 on my doorstep I'd pour in my gravel driveway to keep the dust down.