Re-drives Belt or Chain ?

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rv7charlie

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Haven’t got a clue where the photos were taken, I collect interesting images for inspiration.
If it is indeed the one I saw here in MS, most (likely all, but I don't remember for certain) of the reduction took place in the Honda motorcycle enigine's gearbox. The chain was basically a 1-1 power transfer device. The one I saw actually had a pilot-accessible shifter. He said that he'd run in (IIRC) 2nd gear flying solo, and downshift a gear to get off the ground if carrying a passenger. (Not an effective way to increase power, but I suppose he was able to get by using it.) He did say that he had flown it from somewhere down in south MS to the flyin, in central MS. Would have been at least 100 miles.
 

challenger_II

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Fisher County, Tx. USA
The GO-145 used an offset spur gear, much like a Continental GO-300.

Seems like Lycoming tended to use planetary gearsets in their geared engines; Continental used simple straight tooth spur gear pair.
What did the gearset in the little Lycoming GO-145's look like?
Nose cone suggests planetary. Was there a quill shaft between the crank and the gear input?
 

TFF

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In general, I don’t see someone making their own planetary. Off the shelf from some hot rod transmission gear, yes. I can see someone making a straight cut sun gear and planets. I don’t see very many making the shell the planets drive. That makes the rest look easy. You could get some basic GM stuff for under a grand. The billet stuff would be up there. Building the housing strong enough to take all the forces is fun in its self.
 

Lendo

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V. I believe Gear Lash is a result of allowing acceptable (and much needed) expansion clearances to the gears. If one has one gear inside the other like the Powersport approach the gears expand a almost the same rate and clearances can be tighter.
I don't believe one could adjust a Planetary gearset However there is one Planetary PSRU I like and that's the Mistral development as it's extremely well designed and I assume expensive to manufacture.
George
 

speedracer

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Feb 4, 2020
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Generally, when a cog belt fails, the teeth shear off: the belt doesn't part.
All of the notions thus far proposed have their own set of mousetraps. A considerable amount of
what One uses depends on the amount of power to be transmitted. My personal favorite, for 20-60 input HP, is the Gates HTD cogbelt. It has a good operational history, as long as you keep up with the belt inspection, and replacement.
On my one and only ultralight flight in the early 80's in an Eagle I was about 800' above a big field. All of a sudden I could feel "things" hitting me in the back, RPM went up and it lost thrust. I thought BEES. I shut down, glided down and landed in the field. Turns out the teeth had been coming off the belt and were hitting me in the back.
 

lelievre12

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You can always just use a motorcycle chain.
I think these photos are of Toby Ashley's 2021 Reno STOL drag winner. The interesting aspect is that whilst the engine is a custom build chain PSRU, the serpentine belt in front of the drive chain is the Kawasaki Ultra 310 supercharger belt not fitted in this photo. This 'PSRU' has both belt and chain.
 

Rik-

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San Rafael, California
I think these photos are of Toby Ashley's 2021 Reno STOL drag winner. The interesting aspect is that whilst the engine is a custom build chain PSRU, the serpentine belt in front of the drive chain is the Kawasaki Ultra 310 supercharger belt not fitted in this photo. This 'PSRU' has both belt and chain.
Yes, the belt drive is for the blower and the motorcycle chain is for the prop..

The gear drive on the Yamaha’s apparently have some issues too.
 

Swampyankee

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Earth USA East Coast
Seems like Lycoming tended to use planetary gearsets in their geared engines; Continental used simple straight tooth spur gear pair.
What did the gearset in the little Lycoming GO-145's look like?
Nose cone suggests planetary. Was there a quill shaft between the crank and the gear input?
I wouldn't have any first hand information on that; while there was a (failed) attempt to have the LT101 built by Williamsport (they failed miserably; they didn't have the equipment or skills), there was very little interaction between Williamsport (where they built little motors with stuff slamming back and forth) and Stratford (where they built gas turbines).
 

OMAC

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Thanks to all the members for the time spent in responding to my question. It is appreciated.
 

sming

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Apr 10, 2019
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Whaaat it's already painted and tested on water? I remember him posting his first video on this forum something like last year! There is builder and builder...
 

mm4440

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Jan 14, 2012
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LA area, CA
Bou
Would you mind mentioning where it came from, how you have it mounted up, etc?
BorgWarner marine trans had bolt on reduction units that would go on the back of the FNR part of the trans. Bought many years ago, might be hard to find. I never mounted it but a simple flat plate adapter with a bearing and seal for the input shaft would do it.
 
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