Driving a Honda/Clone from the Flywheel - Honda Part to do it.

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karmarepair

Well-Known Member
HBA Supporter
There is a Genuine Honda part that does just that.

Same 1" shaft as some of the Hondas and all of the clones I have seen described.
Part 23311-Z6L-820. About $180. Add an appropriate taper lock bushing (P2x1 Split Taperlock Bushing [060P21] -$32.95 | Universal Hovercraft) a Universal Hovercraft hub (5-1/2 Diameter 6061-T6 Aluminum Hub [38H550] - $59.95 | Universal Hovercraft) , a backing plate (5-1/2 Diameter 6061-T6 Aluminum Hub Backing Plate [03550BP] -$20.95 | Universal Hovercraft) and your favorite Prop, and Bob's Your Uncle. I SUSPECT this would fit the Clones (Predator, DuroMax, Lifan) but cannot say for certain.

Uses 3 bolts. I'd be strongly tempted to double that.

TiPi

Well-Known Member
Log Member
I wouldn't trust that cast-iron piece with a prop.

Honda has a limit of 50% of engine power for the secondary PTO (I think Kohler is similar, no info from B&S).

I think you would be better off with a prop shaft/extension like this one. Machine a flat face & drill the flywheel for 6 bolts and be safe.
This is how Spacek does it for the Kohler and Briggs engines. Some horizontal engines already have the machined face for a secondary power take-off. You will still exceed the "recommended limit", never mind the "do not use in aircraft" sticker

karmarepair

Well-Known Member
HBA Supporter
I think you would be better off with a prop shaft/extension like this one. Machine a flat face & drill the flywheel for 6 bolts and be safe.

View attachment 99861
I think you'd mentioned the inconvenient flywheel PTO limit in some of your excellent prior work. So much for that idea, ALTHOUGH it might work for bench testing with a wood bar dyno.

My correspondence with Spacek indicated that they could be willing to sell the parts for the Kohler (which they do not name...). For the Briggs 810, it's all or nothing - mods are extensive enough to rule out selling a "kit".

TiPi

Well-Known Member
Log Member
It doesn't mean that it won't work but being outside the manufacturers specification, it probably means some serious testing is in order. OTOH, there are nearly 100 SD-1 flying with the Kohler & the Briggs and the prop attached to the flywheel end (and many Lucioles).
The SE-33 requires modifications to the cover and crank case, so a kit is not a viable option. I'm trying to limit the mods for my engine to the cover only, to make it easier for builders (plus the heads for the extra power).

karmarepair

Well-Known Member
HBA Supporter
This is how Spacek does it for the Kohler and Briggs engines. Some horizontal engines already have the machined face for a secondary power take-off. You will still exceed the "recommended limit", never mind the "do not use in aircraft" sticker
View attachment 99861
Do you know if that is the stock Briggs Flywheel on this SE-33? The installations on the SE-31 engines look to me like they use the stock Kohler flywheel as well.

Vigilant1

Well-Known Member
Lifetime Supporter
Do you know if that is the stock Briggs Flywheel on this SE-33? The installations on the SE-31 engines look to me like they use the stock Kohler flywheel as well.
TiPi can chime in, but if I recall correctly it is a modified version of the original flywheel. He said the stock flywheel was lightened by about 2-2.5 KG. I know there was speculation that the ignition timing was also modified (by moving the trigger on the flywheel or by indexing the flywheel slightly with a modified key/keyway on the flywheel), but I can't recall the details.

karmarepair

Well-Known Member
HBA Supporter
TiPi can chime in, but if I recall correctly it is a modified version of the original flywheel. He said the stock flywheel was lightened by about 2-2.5 KG. I know there was speculation that the ignition timing was also modified (by moving the trigger on the flywheel or by indexing the flywheel slightly with a modified key/keyway on the flywheel), but I can't recall the details.
This looks like the Kohler based SE-31.
The tractor pulling folks advance their timing to suit their fancy by simply omitting the key, or using an offset key.

TiPi

Well-Known Member
Log Member
Correct, both the Kohler & the Briggs use the OEM flywheel. The SE-33 (being originally a vertical engine) doesn't have a flat face machined on the flywheel.

The Kohler CH-series has a 4-hole mounting pad:

The Honda GX630-690 has the mounting pad for their PTO adaptor (3 holes):

Ignition timing should be in the 26-28deg BTDC range for lower compression ratios (under 9), an off-set key can help if the original timing is retarded (like on the Briggs).

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karmarepair

Well-Known Member
HBA Supporter
Not one, but TWO local Mini-Max projects just came up on forii - these are completed wings, with empennage and gear, no fuselage. For cheap. So, one plan I'm examining is grab one of these project, build a fuselage (probably a Hi-Max), and build up an engine and see how it goes. I can buy some of the kit (prop extension for example) from Spacek, and mount it on a Kohler CH750 or 790. Direct drive.