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Technical Forums => Milwaukee-Eight => Topic started by: WhipLash96 on July 02, 2022, 07:51:11 AM

Title: M8 Cases and Cylinder Height
Post by: WhipLash96 on July 02, 2022, 07:51:11 AM
What is largest piston that the M8 will accept before case boring is needed? If I remember correctly, is it 4.310"? Also for those that have done the 131 with the 4.500" stroke, were the pistons proud or sunk in the hole? If they were sunk in the hole, how far were they sunk?
Title: Re: M8 Cases and Cylinder Height
Post by: Don D on July 02, 2022, 09:02:09 AM
131 cylinders are very thin spigots, steel liner. 4.280 us my top then I look to bore cases. I use ductile sleeved cylinders not harley or S&S for the largest bores. From 4.28 next up for me us 4.5"
Title: Re: M8 Cases and Cylinder Height
Post by: Deye76 on July 02, 2022, 04:14:41 PM
Quote from: HD Street Performance on July 02, 2022, 09:02:09 AM131 cylinders are very thin spigots, steel liner. 4.280 us my top then I look to bore cases. I use ductile sleeved cylinders not harley or S&S for the largest bores. From 4.28 next up for me us 4.5"

So, you offer 4.5" M8 cylinders/pistons?
Title: Re: M8 Cases and Cylinder Height
Post by: Ohio HD on July 02, 2022, 04:44:15 PM
John, Moonshine HD has cylinders for 4.5" stroke, and are 4.5" bore. They had a set prepared for George Bryce for his new project Blue 5O that are 4.6" bore. The stroke limit on those I think he said was 4.375".


Moonshine HD 4.5" Cylinders (https://www.facebook.com/MoonshineHarley/posts/pfbid028zExf5GEwpxYD11755o8ofydP6GNW1hswX2enR3pYUesnVU91kBrE26kvPDfpvwdl)
Title: Re: M8 Cases and Cylinder Height
Post by: Don D on July 03, 2022, 06:59:20 AM
Quote from: Deye76 on July 02, 2022, 04:14:41 PM
Quote from: HD Street Performance on July 02, 2022, 09:02:09 AM131 cylinders are very thin spigots, steel liner. 4.280 us my top then I look to bore cases. I use ductile sleeved cylinders not harley or S&S for the largest bores. From 4.28 next up for me us 4.5"

So, you offer 4.5" M8 cylinders/pistons?
Yes. It is a somewhat tricky case bore.
Title: Re: M8 Cases and Cylinder Height
Post by: WhipLash96 on July 03, 2022, 07:01:52 AM
Quote from: Ohio HD on July 02, 2022, 04:44:15 PMJohn, Moonshine HD has cylinders for 4.5" stroke, and are 4.5" bore. They had a set prepared for George Bryce for his new project Blue 5O that are 4.6" bore. The stroke limit on those I think he said was 4.375".


Moonshine HD 4.5" Cylinders (https://www.facebook.com/MoonshineHarley/posts/pfbid028zExf5GEwpxYD11755o8ofydP6GNW1hswX2enR3pYUesnVU91kBrE26kvPDfpvwdl)

I have seen their stuff all over YouBoob as well. I am not sure that I trust them though....
Title: Re: M8 Cases and Cylinder Height
Post by: Ohio HD on July 03, 2022, 07:47:47 AM
Quote from: WhipLash96 on July 03, 2022, 07:01:52 AMI have seen their stuff all over YouBoob as well. I am not sure that I trust them though....

George Bryce does....    he knows maybe a "little" more than all of us put together. But you don't have to buy them based on youtube feedback......   
Title: Re: M8 Cases and Cylinder Height
Post by: WhipLash96 on July 03, 2022, 07:54:27 AM
Quote from: Ohio HD on July 03, 2022, 07:47:47 AM
Quote from: WhipLash96 on July 03, 2022, 07:01:52 AMI have seen their stuff all over YouBoob as well. I am not sure that I trust them though....

George Bryce does....    he knows maybe a "little" more than all of us put together. But you don't have to buy them based on youtube feedback......   
You are correct. The Youboob videos that I have seen were semi vague about what exactly was the root cause of their problems. If it was workmanship, well that will be out of the equation. If it is parts, well, then that is a whole different story.
Title: Re: M8 Cases and Cylinder Height
Post by: WhipLash96 on July 08, 2022, 07:15:23 AM
Quote from: Don D on July 02, 2022, 09:02:09 AM131 cylinders are very thin spigots, steel liner. 4.280 us my top then I look to bore cases. I use ductile sleeved cylinders not harley or S&S for the largest bores. From 4.28 next up for me us 4.5"
I assume that this is on top of a 4.500" stroke?
Title: Re: M8 Cases and Cylinder Height
Post by: WhipLash96 on July 08, 2022, 07:17:41 AM
Quote from: Ohio HD on July 03, 2022, 07:47:47 AM
Quote from: WhipLash96 on July 03, 2022, 07:01:52 AMI have seen their stuff all over YouBoob as well. I am not sure that I trust them though....

George Bryce does....    he knows maybe a "little" more than all of us put together. But you don't have to buy them based on youtube feedback......   
I also heard that Moonshine won't sell the stuff they have unless they do the work. Lets just say that I am not going to go to Tennesee for that. LOL