tazzzz

Im presently running 40:1 ratio in my G-26 and G-38. I want to change it to a 32:1 ratio. Im not sure ,,,,,Do I have to reset the carb? If so ,,which way,,leaner,richer or what, or do I keep it as it is. Both engines are running very well.


Thanks ----TAZZZZ

krayzc-RCU

My Feedback: (31)

i would say put it in there and see what the tach tells u along with flying for the low end adjustment

Kweasel

My Feedback: (29)

The change will not affect the mixture anymore than significant temperature changes. Yes, you should retune for maximum performance.

mmattockx

You will need to go a bit richer on the needles. More oil = leaner mixture.

As Kweasel says, it should not be a significant change, just fine tuning.

Mark

rc bugman

My Feedback: (30)

Depending on the brand of the oil, you may have to lean the needles. Some oils burn better than others and burning oils provide more power than the gasoline.

Elson

karolh

Elson,

In your experience and tests, which oil gave the best balance in protection and power and at what ratio.

Karol

krayzc-RCU

My Feedback: (31)

Penzoil air cooler

rc bugman

My Feedback: (30)

Karol,

more oil = more power because of better ring sealing. 20:1 is better than 40 or 50:1

Best oil for wear: no clue Pat Roy is the expert for this answer. I have completely switched to Pennzoil aircooled.

Least amt of carbon buildup: Belray 1Hr

Most (in my test) carbon buildup: Amsoil (both dominator and saber)

Hope this helps

Elson

karolh

I have read much about the virtures of Pennzoil aircooled but unfortunately it's just about impossible to get here. For the little flying I do compared to others, plus my style of flying which is sport aerobatic where maximum performance is not an absolute necessity, I have found that Bel Ray MC- 1 mixed at 50:1 works well for me.

Karol

krayzc-RCU

My Feedback: (31)

http://oilstore.stores.yahoo.net/penaircool2c.html

FenderBean

I have some questions I just finished breaking in my DA100 can i was using 32:1 now im switch to 50:1 synthetic oil. Im using Bel-Ray MC-1 oil. What can I expect my engine to do? Will it run leaner or richer I did notice it was running hotter, so this makes me think I may need to richen my needles again. Speaking of temps what is the ideal temp for DA100 engine thats broke in?
my temps yestersday we 90 to 140 on the right cyc and the 140 to 160 on the left. Im guessing the left was hotter since its further back. Im thinking about opening that side alittle or add baffles to the left side. Is this too hot?

Kweasel

My Feedback: (29)

You probably won't notice much difference. Warm it up, run it full throttle for a minute or two and retune the carb for best performance.

FenderBean

K thanks

rc bugman

My Feedback: (30)

Fenderbean,

With Belray 1 hr, you need to richen the needles. Since the oil does not burn, more gas is needed for combustion. In a test I ran nearly 2 years ago, the fuel consumption increased between 10-15% with Belray over other oils which partially burned. The same was true with amsoil saber at 100:1.

Elson

mxwrench

My opinions on this subject are:

Some oils burn some don't but very, very few will contribute to the combustion process. What will change when changing ratios is the amount of fuel delivered vs. oil (obviously) and also the viscosity and specific gravity of the fuel will change, hense the need to change the orafice size of the jet delivering the fuel to maintain the same burn rate.

Typically when going to a leaner oil ratio ie. 32:1 to 50:1 you will need to lean the mixture slightly to make up for the change in viscosity of the fuel itself (if you left the setting alone the thinner fuel would flow more through the jet causing slightly rich condition) (some oils are thinner than others so this needs to be taken into account)

Also changing to a leaner oil ratio will increase the amount of fuel molecules for the given volume if passed through the existing carb setting again causing a slightly rich condition. (depending on the amount of change)

Ring sealing is effected to a point as oil is added, but a properly broken in ring shouldn't need alot of oil to seal properly. One benefit of more oil is better heat transfer from the piston to the cyl, and this leads to more power achievable with the proper mixture (allows for leaner settings) (this statement does however indirectly contradict my previous statement).

There is a point of diminishing returns when adding more oil to the mixture. I believe 20:1 is just way too rich, and definitely causes alot more clean up and no evident improvements. Personally I wouldn't run richer than 32:1 mixture.

Oil ratios and fuel mixtures (carb settings) are simply not a cut and dry subject. Trial and adjustment must be made when making any changes to ensure correct running and engine temps.

By the way, I prefer Red Line racing 2 cycle oil over all others (and have tried most all available)

BK

ps. its Belray H1R not Belray 1 Hr ! haha

JoeAirPort

My Feedback: (41)

Very interesting stuff mx. It all makes sense. I never thought about viscosity effect. Very cool.

But I thought that the non-synth stuff did actually add to the combustion process....because of having to richen needles when going from Penz Air Cooled to Racing 2T for example. Maybe it was the viscosity effect.

FenderBean

my oil is belray mc-1 I thought this was what people ran? did I get the wrong stuff?

altavillan

My Feedback: (1)

Regardless of what you learn here tune the engine for desired operating temps. The more fuel you can get into the engine and have it run correctly the longer it will last. So tune it to give acceptable power not absolute max power.

If the base stock of the Synthetic oil is 50 weight and the base stock of the dino oil is 10 weight, most likely opening the needles might be required. Reversed if the opposite.

Hard to guess how your oil switch might cause a need to change needle settings. A simple test. If your engine isn't 4 cycling on down lines it probably is too lean.

altavillan

My Feedback: (1)

Check it out yourself. If it is EGD+ rated it is as good as it gets. Long lost SS uses it I believe but he'll dump just about anything in his engines. Or is that Ralph, I get confused.

Truckracer

My Feedback: (19)

Don't worry there FenderBean ..... MC-1 and H1R are both good oils. H1R does not combust so it pretty much passes through the engine while doing its work. It is recommended for mixes between 30:1 to 50:1. It was also designed for racing engines that have variable exhaust timing valves.

MC-1 does burn in our engines and 50:1 is the recommended mix.

I started using MC-1 2 years ago after visiting with the BelRay people. They said either oil would work just fine for our purposes but they thought the MC-1 would probably be the better choice.

I've been happy with the BelRay oils but I think I'm going to switch to Pennzoil Aircooled this season just because it is much cheaper and easier to find on my side of the city where I live. If it doesn't work out, I'll switch back.

RTK

My Feedback: (1)

Heck, most anything will work Currently I'm using up my Pennzoil air cooled and likin it Might try some of that Bel Ray one of these days. In experimenting, Pennzoil did protect very well on a couple of purposely hot lean runs @ 32:1
When a certain UAV guy worked for a different company they used to go to Walmart for all their UAV flying oil, maybe not the best, but it did the job just fine.

tazzzz

What temperatures should a G-26 and a G-38 run? My readings on the 26 are right around 400 degrees give or take,,,seems to me to be a little on the warm side, using lawnboy at 40:1,,,is why I should run 32:1 to cool it down a bit.TAZZZZ

RTK

My Feedback: (1)

How, where, and when are you taking your temps. Never seen a G26 run that high with adequate air flow and properly adjusted carb. No where close. If you are using an IR temp gun maybe it is off.

tazzzz

Im taking the temp with a duratrax flashpoint gauge at the front of the exposed head right after a bench test after running a tank of gas. The engine was not airborn. TAZZZZ

jbflier

I've used BelRay MC-1 for 7 years without any issues........easy to get at a local Harley dealer.......[8D]