Hacking The Honda Clone - small frame

Very clean inside.
Could you take an even closer picture of the head and piston?

If you can buy a GX200 replacement cylnder head gasket that will give you a small compression increase if you plan on returning this engine to service.

How does the cylinder bore look?
I wonder how much wear you have ?

500 hours and its so clean inside!!!

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Inside the spark plug boot there is a brass threaded part that makes contact with the spark plug.
This unscrews and a small spring and button.
Remove this button and replace it with a small piece of welding rod or copper wire.
This is a RFI noise suppressor and removing it will allow more coil energy to snap across plug gap.

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Is that a small triangular hole in your piston face? If so, is it supposed to be there?

The GX200 has a very very short rod compared to the length of its stroke.
To compensate for this the wrist pin is offset slightly from the centre of the piston to reduce the amount of side force on the power stroke.

In a perfect world the Small block would have a deck about a three quarters of an inch taller, but it had to be a cube shape that fit where the flat heads were installed and the solution was this offset piston.

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it is a marker, but is it pointing to ? no idea where it should pointing :wink:

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Wallace’s comment above explains the piston arrow marking.
So the offset piston pin is located to the correct side of the engine on assembly.
Piston will noise slap and have accelerated side skirt wear if put in 180 degrees wrong.
S.U.

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Made me a poboy’s depth gage for sanding down heads. Bolt is 1/4-20 so one turn is 0.050". Should make a pointer for the bolt.

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Sounds like you been talking to a fellow Syracuse NY…

Very reasonable way to go.
I draw file quite well.
You might want to consider set up a jig for the head to draw file it if you get uneven sanding ( one side higher than the other )

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Hey wait a second…

Garry wrote that book you posted HA HA.
Small world.
“Poboy” is something he would say.

Great guy BTW some of his stuff tricks are in my engines too…

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A poboy could also play with blueing and hand scrapping. Poboy is also a song. I have the best luck with primitive tools. Slow but works…

Prussian Blue, a mirror and Draw filling is my way.
Finnish with a strip off a belt sander.
But yes its slow and steady vice work.

Garry is a great fellow I know him from years back, but we never actually met and I would like to tip a glass with him someday.
We even discussed a Clone for producer gas years ago but I wasn’t really ready to build it.

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Finish off with valve grinding compound on a piece of plate glass.I’ve been told that lapping the block this same way will allow you to eliminate the head gasket. A little aircraft grade gasket sealer supposedly does the trick if the head and block are lapped flat.

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The head gasket most will use for this is about .010.
There needs to be about .030 to .040 bump space between the piston face and cylinder head.
I think using the head gasket would not hurt.

I do lap the heads as you suggest Bruce because I find it gives a head and block a finish that offers maximum grip in a head ( and I have been doing this since the mid 80s on Honda engines ).

As for a sealer if you use a clone or Honda Steel gasket they have a sealer applied to them already.
I find this works real well and most of the time you can reuse a Honda head gasket a few times without much worry on a mild engine.
Here is your typical coated steel gasket with sealer

The other one you see is the thicker GX160 head gasket.
It adds about .060 and will decrease the compression on a GX200.

There are some plane steel gaskets too.
Those I would spray with some sealer just to be safe ( I use some permatex head gasket sealer works well )

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fancy to build your own ignition? :grin:
this might help …

http://www.sportdevices.com/ignition/ignition.htm

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Yes, this is what we have been looking for to solve the problem of a delay circuit creating a different retard at different RPMs.

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What is your intended generational RPM ?
You want your timing set for that range.

I build clones that turn 7000 rpm and manage just fine to run static timing even though its hobled by the propagation delay induced retard…
I have a hard timing understanding why you would need more range than the OEM Honda UT2 ignition can provide with an manually indexed flywheel set the intend RPM range.

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Sorry, wrote “different RPMs”, meant “varying RPMs” for transportation applications.

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I am still confused why you are trying to make a part that already exists in the OEM parts inventory.

We are still talking about the the Honda clone ?

Yes, Honda clone may be my problem. Sorry for going off topic. Please explain what you mean by “manually indexed flywheel.” Does the Honda have a simple way to index the flywheel? The circuit proposed by Koen allows timing adjustment on engines without changing flywheel position.

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Yes use a timing light and move the flywheel to where it works the best at the RPM you want.

I keep getting an error on this video, but from what I have watched he sets his timing as I do.
One difference is I set a pointer on the PTO side of my engine and mark my primary clutch.
I run the engine under load, take a ride, stop pop the flywheel and advance or retard until I find a combination I am happy with.

This way I know exactly what I am getting and can record it in my log for later as reference.
You should have a log on your engine to record everything about it so you do not repeat mistakes and can trouble shoot issues in the future.
I do not use a key.

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