Im in the process of building my first 4 stroke plane using a Saito 100 and would like to know what the fuel mix is compared to a 2 stroke.

don't get caught up in the 4 stroke/2 stroke fuel hype......I run Omega Cool Power 15% in my saito 180 with no problems

For that matter, any good quality fuel with 15% nitro and 20% oil blend will work just fine.  As Jetmech said, don't get all caught up in this fuel stuff.  People in Europe, Australia and other places, have made their own fuel at home and have had no problems with it at all.  Also, don't get caught up in the name brand or color, or any of that stuff either.  Pretty much, if it's a quality fuel (meaning not an off-the-wall brand) it will be fine.

Ditto. 15% Cool Power here too. It only has 18% oil, but that's plenty. I've been using it in all of my 4-strokes (Including a Saito 100) for 20 years now.

I'm another one who runs Cool Power 15% in everything I own. Both 2 and 4 strokes use the same fuel.

Ken

15%nitro, 18% oil in everything, two or four strokes. I burn Power Master but any of the name brands work for me, it's what ever brand I can get the cheapest. Most the time PM comes up on sale in my area.

I am with the gang on this one run the same stuff in 2 and 4 strokes unless your running a YS engine which likes 20%nitro,  15% nitro 20%oil will be fine

Actually the OP's Saito 1.00 will run just fine on 10% Cool Power.

I run a couple of them on 10% and I've never had any problems.

The Saito's have a fairly ( actually amazingly ) broad tuning tolerance range so the extra nitro may be a needless expense.

YS will run fine on the 15% too I've found. Perhaps it isn't putting out its full potential but they still run very well. I'll have to try 20% one of these days just to see if there is enough difference for me to justify it.

Ialso like the Cool Power 15%. Usually readily available around here and has always worked great.

I agree with 'the gang.'

My brother and I fly together. We have a few two strokes and a bunch of four strokes. They all get the same fuel, which is 15% nitro and whatever oil the manufacturer uses. We usually buy 3 or 4 cases at a time and we choose based on price and availability.

We have used these brands and see no difference:
Cool Power
Magnum
Omega
Powermaster
Ritchs Brew
Wildcat

< edit to add copy/paste from Saito manual >
1. Fuel. For maximum protection and loogevity of Saito engines, Saito recommends a fuel containing 20% oil and 10-15% nitro methane. If this blend is not readily available, the next best selection is a high quality 2-cycle glow fuel, such as Hangar 9 Aero-Blend, Omega, Cool Power, K&B, Power Master, etc. Use of fuels composed entirely of castor oil is not recommended. A mix of synthetic-castor oil is acceptable and can be found in the various fuels described above.

I've been adding klotz synthetic oil to my fuel, just a couple oz's. Gives me a nice smoke trail and piece of mind knowing everything is well lubricated. I've been running wildcat 10% in all my engines, but got a case of 15% cheap, that I will be using very shortly. Unless I get better performance from the 15%, soon as it's gone, I'll be back to the cheaper 10%.

I run 20% oil 15% nitro on every engine I own, 2 strokes 4 strokes, .10 to 1.8's

Ido run YS and other then getting them to idle easier and my pocket $10.00 bucks lighter Ihaven't seen any difference between the 15% or 20%. When I tried 30% I noticed how much quicker my pockets got $20.00 bucks lighter!! Ididn't notice much difference using the 10% either, 5% took a lot of work getting the idles set but it does work. The 15% just seems to be a happy middle and it's always around.

Thanks for the replies fellas, most helpful...

Ijust broke in my Saito 100 with Cool Power 10%. That engine is a real powerhouse. Thought the 91 Ihave was the shiz till now..

i run powermaster 20% nitro 20% oil the extra nitro helps 4st idle better and the extra oil is better for lubrication.15%nitro 20% oil will work fine also. in a 2st nitro = rpm's

Any 15%Nitro 18%or more oil will do the job . But the <span style="color: rgb(255, 0, 0);">really</span> important to any Saito .... use 100%<span style="color: rgb(255, 0, 0);">sinthetic</span> oil . Forget castor or blend .

I like the added oil for the smoke trail! I am going to try it next time I can go flying. Thanks Jeff

I have mixed my own fuel since the early 80's, a 20% oil(KLOTZ) and 10% nitro and have run that in every thing 2 and 4strokes in cars, boats, planes and choppers. You don't need 2 and 4stroke fuel. I still have motors from the 80's that still run fine.

Cheers

Horizon is so sold on using 30% Heli fuel in the Saitos, and the high oil content (24%) seems like a good thing, so I'm using it in a Magnum 91 FS in a Fokker DR-1. There is really not a lot of difference in power, maybe 200 rpm at the top end, but the engine starts, runs and idles so much better (and slower) that I always keep one jug of Byron 30% Heli on hand that's used only in that aircraft. It is expensive and messy, tho, oil everywhere, but it gives such a nice smoke trail when airborne. Bottom line: use a good quality off the shelf fuel in it and you won't be disappointed. Saitos are king of the 4s. I've never met anyone who had a problem with one.

This is what got me to asking about the after run oil (air tool oil / ATF, and so on) Saito and the bearing issues mainly the 100. I have one yet to put fuel threw and understand that several have bearing problems. I have a 180 saito running on 10% wildcat with 3oz's of klotz added to it and it is a blend with castor. The 180 and my magnum 91 fs run and idles great, transition to WOT is great no problems at all. I just don't want to have any bearing problems, and now looks like I need to ask why no castor. WOW one question leads to about8 more I do know this when and if I have to replace the bearings they sure will not be HH factory bearings, bocca or something other than factory, but thats another question and another forum I guess. Thanks again for all the replies, even though some have me wanting to ask more questions

SOrry wrong forum thought I was in the after run question I posted.

Maybe for break in, but they really don't need it.

These engines will run reliably with the settings sloberingly rich, that will give them plenty of excess oil.

Once they have been flown a few times, you can lean them out.

Why?

because castor oil leaves a varnish behind after a while that doesn't work and play well with valve gaps and valve timing.....

But aromatic qualities *are* important. We have a control line guy who mixes various fragrances into his fuel. Bubble-gum anyone? Grape? He's got 'em.

Seriously, as long as the oil content is at least 18% and primarily synthetic, it's the same as for 2 strokes.