Originally Posted by SrTelemaster

I'm retired, I don't drink, chase women or do other things that cost me $$$$

My, you lead a sheltered life

Don't worry, I'm standing right beside you except I do chase one woman. Been chasing her for 32 years now. Married her 31 years ago. She still runs to fast for me

Ken

Originally Posted by kenh3497

My, you lead a sheltered life

Don't worry, I'm standing right beside you except I do chase one woman. Been chasing her for 32 years now. Married her 31 years ago. She still runs to fast for me

Ken

Sheltered my A$$, I already drank mine & several other people's shares & lord knows there was a "slut" phase of my life.

I've been married for 27 years myself come May.

I met her just about the time I grew up.

When I was forced into early retirement 3 years ago I concentrated on things that would not cast me $$$$ to pursue like bicycling, XC skiing, kayak paddling & sailing. That leaves more $$$$ for R/C.

Right now, I'm having my abused knees replaced. I am & 90% recovered from aving the right knee totally replaced & I go see the Dr on the 5th to (hopefully) schedule surgery on the other.

I want to be as far along on the left as I am now on the right knee by mid Aprill. To many motorcycle wrecks & other mishaps have taken their toll.

Nice to see a Saito message group here... I have recently bought a used Saito 91 and it idles well and runs well up to half throttle... then beyond half throttle it dies... not sure how to address the issue.

Originally Posted by WYNBOB

......then beyond half throttle it dies... not sure how to address the issue.

Welcome.

Simple answer is....if a Saito dies, its because it doesnt have any fuel. Check your needles, check for a clog, check for holes in fuel lines. Could be as simple as opening the top end needle some.

Get back to us with more details

I have read in the thread that the idle on a Saito FS can be as low as 1,800. My FA150 idles at between 2,800 and 3,000. Anything lower it stops. But it seems a pretty good idle. Any thoughts?

Bottom end too rich.

Mostly I lurk and love picking up information with all the Saito talk. Today I have a question/discussion topic for the experts:

What are the concerns and how could one safely run a smaller prop on an engine than ideal?

I can appreciate the over-revving in flight and the inability to harness the full power, but what are the actual issues and can they be avoided?

Scenario: I have a 1/6 Cub that has a tendency to float in ground effect. I've put a low pitch prop in an attempt to slow the airspeed at idle. I'm currently running a 12-5 and its pretty nice on wheels, but I still have some concerns on floats - mostly that my Saito .65 just barely gets it off the water at MSL 5600. I'm looking to put a larger Saito on, however I'm concern about prop clearance even if I rebuild the landing gear to increase the height, and I was wondering about running a smaller than recommended prop and I didn't want to load it with a large pitch.

Any suggestions?

Originally Posted by maxadventure

Mostly I lurk and love picking up information with all the Saito talk. Today I have a question/discussion topic for the experts:

What are the concerns and how could one safely run a smaller prop on an engine than ideal?

I can appreciate the over-revving in flight and the inability to harness the full power, but what are the actual issues and can they be avoided?

Scenario: I have a 1/6 Cub that has a tendency to float in ground effect. I've put a low pitch prop in an attempt to slow the airspeed at idle. I'm currently running a 12-5 and its pretty nice on wheels, but I still have some concerns on floats - mostly that my Saito .65 just barely gets it off the water at MSL 5600. I'm looking to put a larger Saito on, however I'm concern about prop clearance even if I rebuild the landing gear to increase the height, and I was wondering about running a smaller than recommended prop and I didn't want to load it with a large pitch.

Any suggestions?

The airframe dictates the maximum prop diameter. On a 1/6 J-3 Cub, scale is 12".

You can replace your FA65 W/an FA91S W/O a significant change in weight or physical size, but maybe a smaller engine of similar or greater power? Less weight to yank off the ground.

The now discontinued FA65 is the same series engines as the FA80 & FA91S. (The FA80 is also discontinued) They all share common dimensions except for hieght & they are similar in weight.

The small case Saitos, from FA50 to FA82, share a common mount spec'.

http://saito-engines.info/specifications.html

An FA82 will be 90gm lighter than an FA65 & will make over 50% more HP compared to the FA65. It will fit into a smaller area than the FA65-91 series engines & it will make as much HP as the FA91 albeit in the higher RPM range.

That should allow you to make good power/thrust W/a low pitch prop & not sacrifice a lot of top speed. W/a Cub, top speed need not be of importance as long as you can stay in the Cub flight envelope. Reserve power/thrust @ a scale like flight speed can make for impressive vertical performance & might be able to get you out of trouble if need be.

90 gm is over 3oz in the nose Maybe go W/lighter components behind the CG to balance out?

I would opt for the FA82. Going to the 100 series case will be larger & heavier & you won't need the extra power..

Go W/an FA82. It's lighter than the engine you now have & it will make 1.5HP compared to your FA65's .95HP.

Originally Posted by SrTelemaster

The airframe dictates the maximum prop diameter.

I'm not sure the relevance here, unless you are suggesting I run only a scale diameter propeller. Thank you for all the engine comparisons I have been curious about some of the .80/.82, however - I was specifically asking about running a smaller than optimum prop, and I didn't need any engine suggestions, I have that covered. - sorry for the confusion.

Originally Posted by maxadventure

I'm not sure the relevance here, unless you are suggesting I run only a scale diameter propeller. Thank you for all the engine comparisons I have been curious about some of the .80/.82, however - I was specifically asking about running a smaller than optimum prop, and I didn't need any engine suggestions, I have that covered. - sorry for the confusion.

My mistake, I thought that you had posted that you were thinking of changing engines.

As far as the "scale" prop. I just used that as perhaps being the largest diameter prop due to it being a Cub & a "scale" diameter prop is pretty close to maximum diameter as far as prop clearance during take-off & landing.

Generally speaking, for the airframe & what you seem to be trying to achieve, run the largest diameter prop you can while pitching it for the maximum amount of thrust as long as desired flight speed envelope is not compromised .

Try this thrust calculator. It has come very very close to factory HP spec's on several Saito engines i own, from an FA91S, an FA150, 2 idfferent FA180s.

http://personal.osi.hu/fuzesisz/strc_eng/index.htm

Do a run-up on your present prop & observe HP. Then, adjust prop sizes/pitches via RPM to get the same HP output. Then you can compare thrust & flight speed.

As long as your Cub will buzz around @ a sufficiernt airspeed to suit you, prop it for the most thrust.

Your base line HP might not be 100% accurate & it need not be, It will give you a comparative power/thrust/airspeed factor to calculate from.

maxadventure, you may want to try a three blade prop.

http://masterairscrew.com/manualinst...ROPELLER2a.pdf

Anyone have thoughts or experience on the 150/180 gas conversion kits offered by ST ENGINES. Ive seen video on youtube of several running. Ive read several places that the 180 is not a good choise because of the conn rod. I have a 180 in a Busa 1/4 fokker dviii that I love and hate. Love the sound and power, but hate the amount of fuel it uses. I Never fly it more than 1/2 throttle except to take off. Overkill on power? Ya think.

Originally Posted by vwbuggyhead

Anyone have thoughts or experience on the 150/180 gas conversion kits offered by ST ENGINES. Ive seen video on youtube of several running. Ive read several places that the 180 is not a good choise because of the conn rod. I have a 180 in a Busa 1/4 fokker dviii that I love and hate. Love the sound and power, but hate the amount of fuel it uses. I Never fly it more than 1/2 throttle except to take off. Overkill on power? Ya think.

I neverv could get a relevant e-mail response from ST Engines.

C&H offers the same type of system, aluminum magnet ring. CNC machined hall sensor mount.

Call Adrian @ C&H Ignitions. He will return your call & he has systems made specifically for the Saito 120/150/180.

http://ch-ignitions.com/

What I'm asking is, has anyone done the conversion on a 180 and what kind of a reliability can I expect from the engine. I don't want to spend over 150 dollars just to trash my engine after running it for a short period of time.

SrTelemaster is the master of spark conversions here. He does run his sparkies on glow fuel and not on gas. Same reliability as glow fuel, better economy by quite a bit compared to glow and much easier "handling" compared to glow.

Ken