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9 second bagger?

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Old Sep 14, 2022 | 05:11 PM
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Default 9 second bagger?

This is interesting.. Look at the stock parts he plans to re-use.. I suspect this guy can do it..

 
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Old Sep 14, 2022 | 07:40 PM
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While I'm certain George is a an encyclopedia of motor building knowledge ,he reminds of Kevin Baxter. Another guy who knows motors but takes 27 minutes to explain 2 minutes of information. I just can't do it lol. I guess maybe I'm just an impatient s.o.b.
 
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Old Sep 14, 2022 | 08:26 PM
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Originally Posted by Screamin beagle
While I'm certain George is a an encyclopedia of motor building knowledge ,he reminds of Kevin Baxter. Another guy who knows motors but takes 27 minutes to explain 2 minutes of information. I just can't do it lol. I guess maybe I'm just an impatient s.o.b.

While I can find mistakes in his descriptions one how things work like Baxter, the big difference is that George has a room full of trophies. The guy knows performance.. Baxter is simply trying to sell you something.
 
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Old Sep 21, 2022 | 02:43 PM
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He does seem to ramble on, but that's what happens when you're off script... A lot easier to listen to than Baxter.

Looked good for the miles, makes me wonder why the bike was decommissioned?

I think he'll break a rod. Pretty big bore and lots of RPM. Would be interesting to know how long of a cam he's using to make power up there.
 
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Old Sep 21, 2022 | 04:28 PM
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Originally Posted by PureHybrid
He does seem to ramble on, but that's what happens when you're off script... A lot easier to listen to than Baxter.

Looked good for the miles, makes me wonder why the bike was decommissioned?

I think he'll break a rod. Pretty big bore and lots of RPM. Would be interesting to know how long of a cam he's using to make power up there.
The bigger deal for most is going to be if it would last very long. To many get lead to believe the things that get done in an all out race engine is good for the street, and that is just not the case at all. These big bore engine are very hard on parts as the necessary room to properly fit them isn't there to begin with. If one is to look at the case of the engine there are two hollow dowel pins that do two separate functions. The first function is to align the two case half and hold them in Alignment. The reason they are hollow is they double as the Oil returns from the cylinder heads to the camchest area. The cases can be bored out but you have to leave some material around the alignment dowels so they can do there job! This limits how deep the skirt area of the cylinder sleeve can stick down into the block area. A 4.600" bore piston by itself will just about hit these dowels with no support material left to keep them in place! So what happens is the only cut the bore area into the block and stop above the dowels them self so you have less support for the pistons when traveling around the bottom of the stroke. Then the pistons will hit each other, so they have to notch the two pistons skirts so they do not hit. What this all boils down to is there is very little left on the piston skirts and the cylinder skirts to support the pistons. Then you put the aftermarket longer stroke crankshaft which pulls the piston 0.125" further out the bottom of the cylinder skirt. There is not enough left to keep control of the piston and it effect the wear and length of time the rings will hold the seal!

IMHO you should not use a bore any bigger than 4.375" on any M8 street ridden engine, and even that is pushing to the edge of the limits. Now if your building a hotrod and do not have any problem with rebuilding it evrey 5000 - 10,000 miles have at it.
 
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Old Sep 26, 2022 | 10:34 AM
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George is definitely building a hot rod toy and not a street build. He is using the many improvements aftermarket jugs that Moonshine sells which include deeper skirts that also require extra machine work in the case. He is not using an aftermarket longer stroke crank in fact he is using the shorter 4.375 stroke. As to why he is planning to use even prepped stock rods befuddles me. With the Moonshine jugs it seems to 4.500 bore is working. That said I believe the majority of their builds stick with the 4.375 bore.
 

Last edited by VernDiesel; Sep 26, 2022 at 10:36 AM.
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Old Sep 26, 2022 | 12:11 PM
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Originally Posted by VernDiesel
George is definitely building a hot rod toy and not a street build. He is using the many improvements aftermarket jugs that Moonshine sells which include deeper skirts that also require extra machine work in the case. He is not using an aftermarket longer stroke crank in fact he is using the shorter 4.375 stroke. As to why he is planning to use even prepped stock rods befuddles me. With the Moonshine jugs it seems to 4.500 bore is working. That said I believe the majority of their builds stick with the 4.375 bore.

George has always been an RPM guy.. Short stroke/big bore. All about piston speed. IIRC it didn't work to well on nitro bikes.. They turn slower when naturally aspirated. Bigger bore means harder to hold the cylinder / head in place. More force on the rod..

IIRC the crank has been prepped.
 

Last edited by Max Headflow; Sep 26, 2022 at 12:14 PM.
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Old Sep 26, 2022 | 05:19 PM
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I hear george is using a stock pump and plate wow
 
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Old Sep 26, 2022 | 05:22 PM
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Originally Posted by Ron Coburn
I hear george is using a stock pump and plate wow
What's wrong with the stock plate and pump?
 
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Old Sep 27, 2022 | 11:51 AM
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Originally Posted by VernDiesel
George is definitely building a hot rod toy and not a street build. He is using the many improvements aftermarket jugs that Moonshine sells which include deeper skirts that also require extra machine work in the case. He is not using an aftermarket longer stroke crank in fact he is using the shorter 4.375 stroke. As to why he is planning to use even prepped stock rods befuddles me. With the Moonshine jugs it seems to 4.500 bore is working. That said I believe the majority of their builds stick with the 4.375 bore.
The problem with your above statement is that it cannot be true. As the bore increases the skirts hit each other more and more, so they have to be cut shorter and shorter as bore increases, there is no other way around it! So you end up with short skirts on the cylinders and large cutouts out of the piston skirt on one side of both pistons so they do not hit one another, when traveling around at bottom of the stroke area. So when you cut away the cylinder skirt then cut away the piston skirts, the piston wants to shake rattle and roll as it travels up and down the cylinder and it beat the rings up in short order. Once ring seal is lost it all over. For a race engine that will get rebuild after each race it's fine but would not last long in a street ridden condition.
 
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