mike early

For what it's worth:


1 cc = 0.0338140227 US fluid ounces

cpsdd56

Thanks all, the corsair looks great with that prop much more like I was looking for.Went to the local hobby shop and got some props today,14x7-15x6-16x6. Yanked the motor and mounted it to the stand with a scale to measure thrust vs rpm.I know 16x6 is pushing the envelope but what the heck! I'll compare them to the 2 blade 14x8 zinger and see what I get.Once agian thanks for the input.

w8ye

My Feedback: (16)

With a Corsair ultimate thrust may not be the ideal.

You will have to reach a compromise between thrust and speed.

The 14-8 may be your prop?

mbrennan1

Thanks Ken. I ordered the bearings last night, and not from horizon. Thanks for the info. Now I am going to dig back on this thread for some good instructions on changing them.

RC Specialties

w8ye,

You are right. The corsair is faster on an APC 14x8 2 blade than the MA 14x7 3 blade.

Jim

RC Specialties

sodbuster

The 1/2 inch coupling is the one to get.

Jim

NM2K

My Feedback: (14)

I don't want to drag this thread too far off topic. I'll just say that the formula for horsepower is torque x rpm. You can see that at low rpm, it takes a LOT of torque to come up with a decent HP number, but it can be done. Torque is what performs the work, the rest is mathematic fancy footwork. <G>


Ed Cregger

mike boxtall

Are there any 'how to' videos out there on re-gapping? I finally have my 125 ready for a maiden but it seemed to be running a bit rough. A guy at my field showed me how to do it last year and I can't remember for the life of me.

beaver180

My Feedback: (10)

You've not put it in a Revolver have ya mike??

Paul

mike boxtall

No, I would have had to modify too much just to get proper spacing of the back plate from the cowl. If it were a full build kit I may have put the effort in... but not for an arf. But don't for a second think I didn't consider it. As it is it just barely fits in the Toni as far as depth is concerned.

beaver180

My Feedback: (10)

Haha Thought you might have at least thought about it

Here's how I do it... ( tappet covers are off of course )

Firstly get your engine at TDC , and if you slightly wiggle the crankshft back and forth the tappet rockers will both rock up and down.

Side your feeler gauge under the rocker and above the spring bit ( excuse my terminology ). It shouldn't be tight to push the feeler gauge thru or sloppy. you need to feel the gauge slightly rubbing.

If too tight or loose you'll need to adjust the gap. place your little spanner on the lock nut and insert the allen key ( you call it hex nut?? ) wrench on the little bolt head. Without the allen key turning loosen off the lock nut.

Now tighten up or loosen the allen key ( tiny of a turn ) bit to get your feeler gauge just rubbing. Sometimes I put a little bit of pressure on the bolt head to make it easier to gap the other end better. This is the hard part... you now need lockup the locking nut without moving the allen key headed bolt. Takes a bit of practice but not as hard as it sounds. Recheck the gap once your done, and remember to do this proceedure witha cold engine. And you done

Hope that helps you,
Paul

mike boxtall

Got it, thanks for the help. I knew I had to loosen the hex heads(bolts) I just wasn't sure how or where to adjust with the allen key. Should run better now. I was getting 8200k with a 14X10apc, where as before I was getting somewhere in between 87-8900 depending on the humidity and temp. Starting to cool off at night here dropping down to 8degs at night. Motors run great at that temp, no overheating. Thanks again for the help.

Rudolph Hart

Well don't then..let me do it.Had a 7.5 sabre cl diesel engine years back,torquey as any double size four stroke.

cpsdd56

The 3 blade prop is for a stuka not a very quick plane to begin with, definitley not a fighter. With the 2blade Zinger 14x8 it seems to reach a set speed at2/3 throttle or less and little is gained by giving it more.I think the wing design and size is causing this,70 in. on a .60 size plane.If I can match the thrust of the 2 blade prop at a lower rpm and gain a little more thrust at takeoff up to the rpm limit would this work?

RPMcK

My Feedback: (1)

Guess you really did just want to argue. I had hopes you were actually going to run comparisons[&o]

Ron

retransit

My Feedback: (18)

Ed,
Horsepower is work done over time. The formula for one horsepower is 33,000 lb.-ft. divided by one minute, not torque X RPM. If what you said were true, my Ponticac at 4800 rpm (as measured on a chassis dyno) and 285.2 lb-ft of torque would be giving up 1,368,960 h.p. instead of the 260.6 h.p. it showed.

Bob

beaver180

My Feedback: (10)

Gegay Ron,

Without flogging the old horse ( flogging the horse O.F. ! ) your right about comparing apples and oranges regarding same props on a 2 stroke 1.40 and an awesome Saito 180...

I have a ST motor that'll swing the same size prop that my 180 does at same revs, BUT the Saito weighs much less and drinks ( well now it does ) heaps less fuel. The 4 stroke in this also idles lower and has way better throttle responce and the exhaust note is delightful. No contest!

Gimme a 4 stroke anytime.... but this choice at the end of the day is one of personal perferrence I guess??

Weekend is here, Happy flying Guys !!!

Paul

retransit.... Only 260hp?? wanna hope that wasn't at the flywheel

retransit

My Feedback: (18)

That was at the rear wheels beaver180. Remember I said "chassis dyno". You can add 12% to 15% for flywheel h.p. It's an internally stock '96 TA with BBK headers added after the dyno pull. Max h.p. was 297.1 for the pull quoted. Stock rating is 305 h.p. at the flywheel.

Bob

mike early

oof, I've lost my little valve adjustment wrench.
I see quite a few different tool sets on Horizon for Saito engines. Mine is out of stock.

Are all of these valve adjustment lock-down nuts the same size?

Michaelh

My Feedback: (4)

I can tell you the 1.80's are bigger then the ..82's wrenches. I have 3 sets of for the .82 as this size plane seems my favorite. Let me know if you need a set.

Will work for the .56-1.15

Mike

Rudolph Hart

Hello mike,my engine was bought second hand and the 4mm spanner was missing.Auto shops here only sell sets down to 1/4 inch or 6mm.Went to an electrical shop and bought a tiny set for working on computers and such.Good luck.

mike early

Thanks, guys!

But I found an old WR post on this very topic and went to sears and bought the ignition wrench set.
The smallest is 4mm and works great!

AJsToyz

Engines ?? Yeh thats the ticket !! I have no Idea what I'm talking about ?!

dammitman

My Feedback: (15)

nevermind, its running perfect now with out the twin carb setup.

mbrennan1

I am going to change the bearings in my Saito 125. I have a gear puller for the hub removal. Is there any hints or tricks I should know about to make this a successful task? This will be my first attempt and I am a little nervous.