440 Kawasaki PSRU design, parts, plans, sources

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Skypilot1961

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I'm scratch building a PSRU for a recently acquired Kawasaki 440, water cooled, oil injected, dual carb engine. It's going to be used in a RagWing RW6 (absolutely love this plane!!!).

Would really appreciate any help in choosing the proper drive ratio (thinking 2.9 to 1) as well as prop selection. As with many of us builders, keeping costs reasonable is important.

I'd really like to assemble and share (here) a set of plans and parts sources for the finished PSRU for this project and hopefully (with some minor adjustments) other builds using the 440/340 Kawasaki engine.

So where do I start?



Thanks and CHEERS!!!
:beer:
 

Armilite

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There are some Belt Drive plans on ebay.

First you have to figure out what your 440 engines, rpm power band range is with the pipe your going to use. You don't want a Tuned Pipe for plane use, that has a Flat Spot in your Flying Power Range, usually in the 3500rpms to 6250rpms. Most use 2000rpms to 6500rpms Max for plane use. 6500rpms, is only for takeoff, MAX Power! So what HP does your engine make at say 6500rpms? Once you now the Max Rpms you will use, then pick out a Belt Drive Ratio for your plane depending on what prop you want to run. What is the biggest prop you can swing with your plane. Look at what others are using on the same type plane. There are many different 440s, single, and dual plug also. Most people use the 440A with a chaperell #7 or #8 sled pipe. If you have a 440B, 440C, you will probably have to design a pipe for it. There are cheap programs for doing that. A 2.58 to 2.6 ratio is a common used ratio on most Belt/Gear Drives, or higher. Most stock 440s make 40-48hp at 6500rpms. Also look at your compression ratio, so you know what octane of gas to use. All Rotaxs require 91+ by Rotax.

Does you 440 have 4 Holes on the PTO end? If so, you can also use a Rotax Gear drive with an Adapter Plate.

Rich
 

fly_boy_bc

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I am also working up my PSRU and Prop parameters but I am a bit befuddled.

Roger Manns engine prop PSRU matrix for the 440a seems to indicate 2.9:1 ratio and a 72 inch prop. I can not find any ground adjustable props that size! My fisher 101 is normally equipped with a 60 inch prop (clearance). I can extend the undercarriage somewhat but I doubt I can fit a 72 inch prop no matter what I do...Am I missing something?

Gary B in BC with Fisher 101
 

fly_boy_bc

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Roger Manns engine prop PSRU matrix (the single most trusted source for Kawasaki PSRU and prop information) for the 440a indicates 2.9:1 ratio and a 72 inch prop:
***************************************
These are some thrust check stats. that Roger got:
340 LC, 2.9 to 1 belt, 70X26 prop- 205 lbs. at 6800 RPM
340 FA, 2.8 to 1 belt, 68X26 prop- 190 lbs. at 6600 RPM
440A FA 2.9 to 1 belt, 72X32 prop- 225 lbs. at 6600 RPM

The stats. below with a shorter prop. are ok but not as good as above.
340 LC, 2.6 to 1 belt, 60X28 prop- 165 lbs. at 6800 RPM
340 FA, 2.6 to 1 belt, 58X26 prop- 155 lbs. at 6600 RPM
440A FA, 2.6 to 1 belt,60X28 prop- 160 lbs. at 6600 RPM

Note: The difference between a 340 and a 440 is
piston size, a 340 can be made into a 440.

I ABSOLUTELY do not recommend using any Propeller
Speed Reduction Unit(PSRU) that uses a 2.0 to 1 reduction. This sets up
harmonics that are dangerous. Several failures have been recorded. I also do not
recommend the 440B which is 48 hp but cannot be cruised between 5500 and 6000
RPM.

As shown above the best performance comes when using a longer prop.

How do these engines compare?
Rotax 277, 2.58 to 1 gearbox, 60X28 prop-160 lbs. at 6800 RPM
Rotax 503, 2.58 to 1 gearbox, 64X34 prop-200 lbs. at 6800 RPM
Rotax 503, 2.9 to 1 belt, 72X38 prop-260 lbs. at 6800 RPM

Most people who are dissatisfied with Kawasaki engine
packs are swinging short props with something below a 2.6 to 1 ratio. Much time
and money has gone into the short evaluation above but it proves that once set
up properly the 340 can't be beat for the money invested.
**********************************************************************

I can not find any ground adjustable props that size! My fisher 101 is normally equipped with a 60 inch prop (clearance). I can extend the undercarriage somewhat but I doubt I can fit a 72 inch prop no matter what I do...Am I missing something?
 
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fly_boy_bc

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That goofy little calculator is for tiny models. I can not make it work in any way that makes ANY sense.
 

clanon

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Let's Agree to disagree.
PS:I was ready to tell ya how those PSRU and prop combos relate...but i won't
Maybe when you understand :
prop ; psru ; thrust ; pitch ; RPM ; torque ;HP ; drag ;lift ; efficiency ; climb ; cruise ; take off ; etc ;etc.
Sure left some out...
 

fly_boy_bc

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Let's Agree to disagree.
PS:I was ready to tell ya how those PSRU and prop combos relate...but i won't
Maybe when you understand :
prop ; psru ; thrust ; pitch ; RPM ; torque ;HP ; drag ;lift ; efficiency ; climb ; cruise ; take off ; etc ;etc.
Sure left some out...
Excuse me? I understand all of those issues rather well. I also completely understand "how those PSRU and prop combos relate".

My question is why nobody seems to be using the emperical evedence gathered by a respected plane builder like Roger.

Almost nobody uses props the size he suggests. Sure many planes are limited by max prop diameter but even those can have their gear extended in order to use a bigger prop.

P.S. Your suggestion to use a 60" prop would reduce my potential static thrust by 65lbs.....Thats more than I am willing to give up due to short gear legs.
 

fly_boy_bc

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I found this on a Yahoo group:

I personally have owned a 340FA Kawasaki/ 2.9 to 1 belt drive,
swinging a 70in Ivo Prop. That package was mounted on one of Roger's
designs called the Ultra-Piet that was built by me with considerable
help form a very good friend of mine. I had a very good experience
with this combination.

This seems to verify that the longer prop works well on this engine but does not indicate static thrust/climb or anything else. It DOES show an appropriate reduction ratio however.

What it boils down to is Rogers numbers are ideal but most Kawasaki users can not use a HUGE 72 inch prop due to clearance issues.

I plan to extend my gear legs as much as is practical. I may end up a little "Storch like" but the Fisher 101 is pretty short to begin with so it could easily work with a little higher stance.
Hmmm...12 inches is really only 6 extra inches of gear height, so to go from 60 inches to 72 inches sounds doable to me. I will extend the gear first to verify what extension I can get then work out the reduction ratio.

From what I can see 72 inches is quite possible but 70 inches would probably be more practical, requiring only 5 inches of gear extension..Bigger tires could make up most of that!
To suggest that 60 inches is the best way to go just because of clearance ignores the fact that 65 pounds of static thrust can be gained by extending the gear!
 
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fly_boy_bc

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GSC does indeed have a 72" ground adjustable wooden prop at a great price! They concur that 72" is the most appropriate diameter for a Kawasaki TA400 with 2.9:1 on a Fisher 101 as long as I can get the clearance.

Also they are 3.5 hours from my home and in my own country!

She's gonna climb like a homesick angel!
 
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Armilite

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Excuse me? I understand all of those issues rather well. I also completely understand "how those PSRU and prop combos relate".

My question is why nobody seems to be using the emperical evedence gathered by a respected plane builder like Roger.

Almost nobody uses props the size he suggests. Sure many planes are limited by max prop diameter but even those can have their gear extended in order to use a bigger prop.

P.S. Your suggestion to use a 60" prop would reduce my potential static thrust by 65lbs.....Thats more than I am willing to give up due to short gear legs.
===============================================================================

Couldn't you compensate for that two Blade 72" Prop, by using a 60" or shorter prop, by just going to a 3 blade to get the same thrust numbers you want?
 

Armilite

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I'm scratch building a PSRU for a recently acquired Kawasaki 440, water cooled, oil injected, dual carb engine. It's going to be used in a RagWing RW6 (absolutely love this plane!!!).

Would really appreciate any help in choosing the proper drive ratio (thinking 2.9 to 1) as well as prop selection. As with many of us builders, keeping costs reasonable is important.

I'd really like to assemble and share (here) a set of plans and parts sources for the finished PSRU for this project and hopefully (with some minor adjustments) other builds using the 440/340 Kawasaki engine.

So where do I start?

Thanks and CHEERS!!!
:beer:
These Plans are on ebay a lot. There are others. Anything 2.6+ would be good. Hirth/Challenger use's 2.6. The most popular gear drive ratio was 2.58 on Rotax's.
 

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fly_boy_bc

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===============================================================================

Couldn't you compensate for that two Blade 72" Prop, by using a 60" or shorter prop, by just going to a 3 blade to get the same thrust numbers you want?
Nope, NOTHING makes up for having a lower diameter than that which is optimal. Yes you CAN use a 60 inch prop on this engine with an appropriate reduction ratio but adding another blade does nothing to make up for less disk area. This would result in lower than potential static thrust. On a slow flyer (like mine) getting the highest static thust is important to getting a decent climb rate.

If I can not get 72 inches due to clearance issues than I will just install the largest diameter I can get away with by extending the gear and using what on my little plane will look like "tundra" tires.
 
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tlcasey100

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Jan 19, 2011
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Location
Hominy, Oklahoma 74035
I'm scratch building a PSRU for a recently acquired Kawasaki 440, water cooled, oil injected, dual carb engine. It's going to be used in a RagWing RW6 (absolutely love this plane!!!).

Would really appreciate any help in choosing the proper drive ratio (thinking 2.9 to 1) as well as prop selection. As with many of us builders, keeping costs reasonable is important.

I'd really like to assemble and share (here) a set of plans and parts sources for the finished PSRU for this project and hopefully (with some minor adjustments) other builds using the 440/340 Kawasaki engine.

So where do I start?



Thanks and CHEERS!!!
:beer:
Im building a rw5 and my plans call for a belt drive at 2.9 ratio if that helps!
 

Armilite

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Herbgh

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===================

There is a 3D Model, Free on www.grabcad.com for a Kawasaki 340/440.

I would think the ACE Belt Drive could be Adapted also.
I have most of those parts...and the engine I would like to adapt it to is a Kawasaki TC440D.. Water cooled, dual ign,elect start engine...Wish I knew more about it...anyone
 

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Armilite

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I have most of those parts...and the engine I would like to adapt it to is a Kawasaki TC440D.. Water cooled, dual ign,elect start engine...Wish I knew more about it...anyone
============================

I have seen a few of these Dual Plug Water Cooled Engines but didn't know there was a D Model, I have only seen reference to the A, B, C, Models. Most People want the 440A Model. Never seen a Water Cooled 340/440 put on a Plane. The 340/440's came as Free Airs, Fan Cooled, and Water Cooled, both Single & Dual Plug versions.

First, ascertain what Year Engine it is. Cylinders usually have a Casting Date, if it says 80, it's for the next Year 1981.

2nd, it's probably Best to find the Year Shop Manual off eBay or some Vintage Web Sites have downloadable Manuals as pdf files.

It's (68mm x 60mm) 435.9cc.

On eBay, they list Pistons for:
Wiseco Piston Pro-Lite 68.00mm Kawasaki Intruder 440/Invader 440/Drifter 440 so that was probably what Kawasaki Sleds used them. There were 367+ different Brand Name Snowmobiles at one time, some also used these Kawasaki Engines.

Downloadable Manual.

On eBay!

1981 Kawasaki Drifter Snowmobile SB340-A2 SB440-A5 Shop Manual Supplement

Kawasaki Snowmobile Drifter Shop Manual SB440 SA340 SC340

1980 Kawasaki Snowmobile Invader Assembly Preparation Manual 99964-3520 SM170

Kawasaki Invader Assembly & Preparation Manual # 99964-3510 in English & French

Kawasaki 440 with a Tuned Pipe Dyno Sheet!
KAWASAKI 440 - 63hp at 6750rpms.jpg
 

n3puppy

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I have most of those parts...and the engine I would like to adapt it to is a Kawasaki TC440D.. Water cooled, dual ign,elect start engine...Wish I knew more about it...anyone
Watercooled, 4 sparkplug, 1 piece head narrows it down to a 1981 or 1982 engine used in the Kawasaki LTD snowmobile. (2 years only)

Fairly high strung motor - 76hp @8200 rpm Using dual tuned exhausts.
It's claim to fame was the fact it had 8 transfer ports to move a lot of Air required for that [email protected] high RPMs
For aviation use the Dyno graph shows around 45-50 hp in the 6000-6500 rpm range.

The Shop manual for your engine has about anything you need to keep it running.

If it still has the original Keihn Butterfly carbs they are very different as far how they are tuned/jetted etc. compared to Bing or Mikuni slide carbs. The shop book has the info on what to do.

BTW - from what I can tell it has a fairly high compression ratio - 12:1
Even though the manual says minimum 89 octane I'd run good 93 pump gas or better.
983BC7A8-81EC-4B48-8F0C-8D58C591170F.jpeg40ECCCFD-6856-4E73-B6C3-931FC7137E3D.jpeg
 
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