Bonneville America Forums Forums General Motorcycle Forums Other Bikes the fatboy

hey guys i just got my brand new speedmaster on the 14th and i love her, better than any other bike i've ever been on. heres the catch i was riding around town with one of my buddys he was on his 00 fatboy with pipes and carb. we both took off from a light at a moderatly fast pace and i was in 3rd gear checked my mirror and had to hit my brakes go down a gear and wait for awhile for him to catch up. whats the deal with that i thought he was gonna destroy me in a race, what does triumph know that hd doesn't? he has almost twice the cc's. needless to say i'm even more pleased with my new family member now.

Twice the cc's doesn't make up for wrist flexability... Was probably more the rider.

i would bet more rider also, but i know that my bike with everything done to it can take a 88ci with no mods accept for pipes

Frank

Unless it's been rebored, that would be an 88 inch twincam. Those don't have near the poopypower of the 96 inch engine and even that is barely a match for the 800 Triumph going through the gears. Now, don't get me wrong. The 96 incher will eventually haul arse, reaching a tonne up with 2 gears to go, it just takes it a while because there are 2 large flywheels and a heavy alternator rotor to spool up. On the B engine, there are also a pair of hefty balance shafts too.

Depending on the amount of chrome billet doo-dads, the Fat Boy can be well over 200 pounds heavier than your Speedy. That's worth a lot of horsepower.

We call that "Hog Slaying" Seriously though, That Fatboy is probably putting out somewhere around 65 RWHP. Your new Speedie is roughly the same, but with a 240 pound weight advantage, your power-to-weight ratio is like you having an extra 15 or so HP "in the bank." In other words, That Fatboy would have to have close to 80 RWHP to keep up with your new Speedie!! Congrats on the new bike and have fun roastin' those hogs!! Scott

My friend purchased a HD fatboy 88cu inch and sold it 6 months later because he said it didn't have enough power to get out of its own way. He ended up buying a Honda Valykrie. I JUST test road a brand new DYNA Sponge Bob and must say the performance was just as lackluster as described in this post. I know I could have taken it off the line with my SM but it would have caught me further down the road.

they move really good once you spend 30,000 on them...

a guy I know has a dyna twin cam 88a (unbalanced motor) with a 103'' (I think) kit and a mikuni 41mm flatslide, plus some other stuff and I think it puts out around 90-100 hp and about 100 ft-lbs. It does weigh 650-700 lbs though...and I think he has dang near 30k in it...

Seems like with Harley motors the HP possabilities go a lot higher. Maybe that is just due to the larger displacement giving it larger potential?

I think it's because the stock compression ratio is so low, around 8.5-1, bump it up to 10.5 or 11-1 and all that displacemenet really shows itself. Of course you have to buy an expensive new starter, clutch, and possibly primary to handle it...

road warriors have 8.5 stock and make much better power than harleys

Frank

Well I can tell ya my SM sucks up my friend Night Train every time. He has a bigbore kit on it a 6 speed tranny and dyno tune box and is fuel injected. I don't destroy him but he can't catch me either. And I am talking on straight road not twisties on the twisties I smoke him.

Hardley is never fast doesn't matter what they do. They can be fast for a Hardley but not fast. The fastest Hardleys I have ever seen have been built shovels. But I am talking SS big bore jugs , polished and balanced crank, stroked , chevy valves and manly keepers , crane springs , wiseco racing pistons, etc.. and still couldn't get away from my 66 TR6C with little more than 10.5:1 pistons.

I won't get into all the technical jargon. I eat crap like Fatboys for breakfast (even the 1450cc engines). With that in mind, a friend with a Deuce runs off and leaves me, but he has spent $6,000 making it go.
I've spent about $60 at Brent's place making mine faster.

haven't found a sportster yet that can take me. V rod yes but that is a racing motor taken from the track and made to fit street purposes. Cubic inches don't make speed. I used to play with chevys alot (still do) A well built small block will suck up a similar big block every time. I like big block just because but they are way too heavy they pull nice and make good truck motors. Until ya start talking aluminum so the weight is gone. Same goes with big Harleys like I said I have a friend who did the big bore kit on his night train plus more that I stated above and can't even come close to catching me.any Harley is more cubes and can't catch a Triumph same was true with the 650 in the day. A 650 triumph kills a shovel or pan almost every time.