2 Stroke Oil In Fuel.

Hi Guys,
This is my first post so please be gentle.
I have recently purchased a 2009 TXC250.
Going through some of the posts here and people are recommending running 2 stroke oil at 200:1 for valve longevity.
Any oil in particular?

Thanks

Neil

probably any good 2-stroke oil, I'd guess.

but really, the amount of oil you're gonna have in a tank (~40cc/ >1oz) any motor oil would probably do.

Its a waste of time (and money) and will do nothing for the longevity of your valves

I am not sure about this but the added carbon deposits can probably do more harm than good, don't they ?

Guys; I have been doing this for over 20 years since lead was taken out of fuel. I firmly believe that my bike stays in spec longer, I have yet to require top end (valve/seat) work, the top ring certainly gets protected and at 200:1 the plugs do not foul nor does the bike blow smoke. I believe I have extended the bikes longevity by using racing 2 stroke oil. No empirical evidence to back this up just 55 years or riding dirt bikes.
PS I run injector cleaner through the fuel about twice a year.

When I raced cars that ran on methanol I would put a quart of oil with lead additive in 55 gallons of fuel. It reduced valve guide wear and the lead protected the valve seat from trying to spot weld itself to the valve. That being said I believe it is less necessary if you're using good fuel with no alcohol. If you decide to use oil I recommend a full synthetic and not very much of it and I'll add that the smarter thing to do would be to use race fuel with lead in it or at least mix some race fuel with your ethanol free pump gas.

I don't bother. When I raced a 13k rpm redline Yoshima Honda with the then new white gas and other unleadeds (mid to late '70s), Kaz would recommend mixing in some leaded fuel for the valves. I assume engines today are designed for the fuels we use today. Never had a valve issue ever except dropping one at 15k+ because I was too lazy to change a failing shifting fork.

"We also get questions about lead being used to keep old engines running longer. We do not add lead specifically to promote valvetrain life in older engines, but indeed that is a benefit, especially for vintage racers. Many older engines were built without hardened valve seats because lead in fuels helped extend the useful life of exhaust valve seats. If you own an older race car that still uses the stock cylinder heads, consult with your race engine builder about leaded fuels."

https://www.sunocoracefuels.com/tech-article/race-fuel-101-lead-leaded-racing-fuels

Not saying adding the oil is a bad idea but I tend to defer to my engine builder for the best info.

Oil is not a lead substitute, and modern engines don't require (or benefit from) any additives to the fuel to protect the valve seats. The valves themselves require nothing

There is zero reason to do this and as far as I can tell it provides only negative consequences, as small as they may be.

I don't think anyone here claimed oil was a lead substitute. Oil can and does help the valve guides which in turn keeps the valve seating accurately preventing valve seat wear. Lead is an excellent ani-knock compound and also coats valve seats and the valve which prevents metal transfer in extreme conditions. Even if you don't believe it's necessary it doesn't hurt anything unless you have a catalyst in the exhaust flow which includes an oxygen sensor in which case the lead will coat it over just like it does to the valve only coating it over stops the chemical reaction making it inoperative. I agree that it's not required, I disagree that there is no benefit.

Will a little oil help the fuel pump last longer? Someone on this board recommends it.

Do it for the faint smell of heaven if nothing else!

A few racers I know that race Four Strokes swear by Marvel Mystery Oil. Just a capful or so added to the fuel tank keeps the valves clean.

it's not going to hurt anything- that's for sure.

in fact, I think that a small bit of oil would help in a few areas where fuel evaporation causes problems (injectors, pumps, carb orifices). I believe the heavier oil condenses out first, then the "varnish" (solids), as the volatiles go up into the atmosphere. Later, liquid fuel can "clean" out the solids better since they're not adhering to the metal surfaces, but have a layer of oil under them. This is a working theory that i've been mulling over for about 20 years- not an accepted fact.

It's a huge problem in 4 strokes where someone leaves the petcock on for 6 months- the carb is almost like plastic-dipped with varnish when a tank of gasoline is evaporated through the float bowl. It's not as bad with a pre-mix 2 stroke under the same conditions.
btw, turn your petcock off on your older bikes and solve this issue.

That was in response to the previous post about lead substitute and only to confirm that it's not the valve (as has been the topic of discussion) but the seat that under some circumstances (but not this one) would benefit from some lead additive. I build 4 stroke heads professionally and have been for many years. The valve, seat and, guide don't need your help, not that premix at 200-1 is actually going to do anything, but it's not necessary, could cause deposits, (especially) if using synthetic, and definitely costs money that can be spent for an actual benefit.

Nobody here is talking about running methanol, for which the main benefit of using premix was corrosion control, ethanol is not methanol, and 10-15% ethanol will require nothing.

My thoughts are that you could just go ahead and do it, or use the money to go out for breakfast on the day of your ride instead. Either one will have the same affect on the longevity of the top end of your motorcycle.

Actually the breakfast will make you heavier and put more load on your motor causing it to wear out earlier. Just messing with you !

Clearly not for everyone and thats OK. I just rely on my own experience of particularly long term upper engine components staying in spec, comp holding up and never letting me down.
Like DD's 450 my 310's (09 and 10)are long lived yet fire up straight away, dont smoke have stayed in spec since their first adjustment and have heaps of miles accumilated over some pretty adverse condition.

The reason I mentioned methanol and alcohol as in ethanol is because all kinds of alcohol become extremely corrosive when they absorb moisture out of the air and oil in the fuel can slow or prevent the corrosion. I recommend using race fuel like VP110 over pump gas because there's no alcohol in it and no need for any additives. I also professionally built racing engines since the mid 1980s that in many cases the sum of the parts were in excess of $20,000.00 (the fuel used didn't "require" lead or oil but adding it helped and was not expensive) and they had hard seats in aluminum heads and stainless steel or titanium valves which can be problematic because they are prone to wearing valve guides thus reason to add a lubricant to the fuel. The engines that I built could be ran on many different kinds of fuel just like motorcycles that can have anything from pump to oxygenated race fuel. The amount of premix that someone puts in a tank of fuel on a motorcycle is the equal to about a cap full. I don't know what you eat for breakfast or what you pay for premix oil but you might want to crunch the numbers again and read my first post again. I was giving an example of a situation that does require adding oil and lead and then recommended better fuel as a solution.