FM dyno'd the stock M8 107 at 81hp and 99 ft lbs, the stage 4 twin cam is a bit more, but it isn't all about the peak numbers. My $995 FM 107 twin cam should be putting out around 102hp and 115 ft lbs. and it's got a really broad torque curve with the Woods 555 cams.

 

I went with a 107 build. Unless you had warranty concerns and as you bike is I would assume this not to be an issue I would go after market. Fuel Moto, Hillside and a few others hang around the engine and mechanical topics section of this forum. I suggest you post your questions over there and get ideas from the guys that actually build motors for living. I know if you're not doing heads a 107 can be had pretty cheaply.

 

the stage 4 twin cams ive seen are quite a bit more. Around 115/115. Theres no stock 107 m8 keeping up with that

 

Oh, HELL no.

Stock 107 puts around 75 hp to the rear tire, stock 103 around 68. Not that much difference. You sure as hell don't need a Stage 4 to make another 7 hp.

My stage 2 103 is 100 to the rear tire, and 105 tq.

Yesterday I rode a stage 1 107, Rhineharts, SE a/c, tune. I'd eat it alive.

 

1. I appreciate everyone痴 input here and I知 going to check out Hillside and Fuel Moto and look into. Doing it without a stage 4 or big bore kit

 

Please read the rest of the post. This is what I said In my opinion you would need a stage 4 103 to out perform the 107 M8. A stage 3 would definitely keep up with one if tuned right. If the 107 gets stage 2 you would be out of luck with the Stage 3. A stage 4 will blow away a stock 107 M8 for sure. I also said a stage 3 would keep up. One of the M8's can put in a cam and you would never know it if you weren't told. That stage 2 or 3 will likely be wondering what happened. Seen it happen several times here. I am not talking about using all Harley parts either on M8 or Twin Cam. A stage 4 103 and a stage 4 M8 which will be either 114 or 117 with after market cams will be the winner. Larger Cubic inches needs cubic dollars to beat it. This is with Harley stuff in the M8 other than cams. Sure you can run the compression on up on the 103 and make it larger cubic inches and keep up, but you're going to push the crank to limits for sure. You also can't make it sound stock like the M8 can with the right exhaust. I personally still like the sound of the Twin Cams, but have rode several of the Stage 3 and 4 M8's and lots of Twin Cam stage 4 103's, 107's and 110 and they run well and all with CNC Harley heads. The Stage 4 M8's just run stealthy and they are in their infancy of performance mods. Be careful what you pick on.

 

I wasnt picking. Everyone else read it the same as i did so all i can say is it didnt come out the way you meant it to or the way you thought it did. I sure hope a 114 or 117 can out run a 103 or 107.

 

I didn't think you were picking. Wasn't trying to insult you either. You are right I didn't explain my thoughts just right. I ride with several guys around here that have M8's. I have a stage 2 with game changer in Rushmore and can keep up with stock 107. Problem is of the 6 M8's none are stock. Three claim to be but have drop in cams and good tunes. Don't stand a chance against them. Easily 10 more hp. Another has 114 stage 3 and he does out do them. Another has a 114 stage 4 with Harley cams and good tune and he is very light and it runs very well. The last one has a stage 4 117 with after mkt cams and he doesn't dodge anything including a 120R. He is also talking about going to 124. What I am saying is you can't trust a M8 to be stock and you really can't tell if it is or not, until too late. It can be a 114 or 117 and can't just listen to it and tell if it is. It will take a good Stage 4 Twin Cam to keep up with a Stage 4 M8 that sounds stock.

 

THIS is a Carabau. The Philippine equivalent of a farm tractor. They race Carabau at fiesta time...



THIS is a fast motorcycle.

Now for my (sincere) question. Why?

If you ride a Carabau (and I *LIKE* my Carabau!) why try to make it fast?

If you want a fast bike, why not just buy one?

There may be some irony in the idiom "you cant make a silk purse out of a sow's ear." A sow is a female hog

Is this a one-upmanship thing, among a bunch of rich old frats? Or what? I just don't get it.

The simplest of logic tells us that trying to ride that Carabau fast might not be the best idea you ever had...