Milwaukee Eight Engine Configurations

Hey, it's Mike Roen, Fix My Hog. I got a nice little informational video for you today and it's gonna be going over the M8 configurations. You know, it's kind of hard to believe that the M8's already been out this little long but really right out of the gate in 2017 this thing started getting modified. You know, cylinder kits came out, Big Bore kits and they just kind of kept pushing this thing to the threshold of how big they were gonna go with it. So I got a little diagram here and we're gonna kind of go over that and just show you what I'm talking about. So if you look at it here, you know the factory M8 107 came out, pretty good package. You look at the bore and stroke and then they offered a big bore kit, you know, right outta the gate. You could make that thing a 114. I was like, hey now that's a good deal. The thing I like about the, when you take a 107 you bore to a 114, you get a special piston you get a high compression piston. All right. If you look at the factory a 114 configuration and you compare it to the Harley Screamin' Eagle configuration, it's different. So the bore and stroke are. And this is where it kind of gets confusing. So depending on, you know, the parts you're ordering you wanna make sure you're you're ordering the right parts for the right configuration. So there again, so now you got a Screamin' Eagle, that's when you take a 107 and you put the 114 cylinder kit on it, that's how they achieve it. The factory, when they build it, they've got a bore and stroke of four inch bore and four and a half inch stroke. That's how they're achieving it. And you know, what we've found is when you take the 107 and you buy the factory Screamin' Eagle kit it comes with a much more desirable piston. It comes of the dome piston and time and time again anytime we dyno tune the Screamin' Eagle 114 kit as opposed to the factory 114 they always make better power because the factory 114 comes with the flat top piston. And this motor evidently likes compression, you know depending on the cam you're choosing. So that's something to make a note of. You can kind of go down the list and just pay attention to, you know, your bore and stroke and see how they achieve it in every way they do it. And that's kind of what this whole video's about. On another note, if you're looking at the factory 107 cubic inch sleeve it can be bored to a diameter of 117 cubic inches. Another thing I wanna bring to your attention is the thickness of the cylinder sleeves cause that varies to how big you can make the bore. So, okay. The factory 107 cubic inch the thickness of the sleeve allows it to be bored to a maximum bore of 4.125 which with that stroke makes it a 117. However, the factory 114 and 117 cylinders have a thicker sleeve and they can be bored to a dimension of 4.18 which is equivalent to a 124 with the appropriate stroke. The case spigot bore is the same between each cylinder or between each engine. So that's kind of something else, you know you're gonna wanna do a little research on before you make your decision, cause you know, it comes down to how big an air pump do you want, you know what cam are you gonna run? What throttle bar are you gonna run? Do you have an exhaust system? That's even gonna support a 128 or as you can see they added in a 131. So it's really gonna come down to, you know what you want when you're done. Everybody always thinks bigger is better but there again, you know, depending on what year your M8 is, what oil pump you have in it? You know, if you're going this far you're obviously gonna be updating that oil pump to the latest and greatest oil pump or you're gonna be putting in say a, you know a decent quality, maybe SNS oil pump or something. And cause your concern is, you know, something, you know some of the M8's have had that. And when that happens, you know, that's a 128 that had a severe something problem and then it ended up, you know, ceasing the cylinder. So you gotta just really do your your research and that's what this whole video's about just to bring your attention. So, all right. Check out the website, Fix My Hog. We got all sorts of good videos on there. Thanks for tuning in.