Got 103ci Big Bore Done - not the greatest HP result.

[tallroller]

Hi,
Well time to intro myself after weeks of reading the posts - great stuff.

2 mths ago I traded my Victory Kingpin for 2009 Road King Classic. Already done a bunch of stuff on it:
16" internally wired apes with heated grips, braided cables. A bunch of chrome upgrades, extended levers (yeah, I trully am tall 6'7") and most importantly got SE performance air cleaner kit with true duals V&H big shots. The sound is awesome.

I wasn't really happy with the gain in power and at app 3,000 kms or 2,000 miles, I completed a 103 SE big bore, race tuned and dynoed at the H-D dealership - all covered under the warranty. The shop only ran up to to 4500RPM dyno test due to the new works done - and the numberts weren't so encouraging i.e. HP showed barely over 70 while torque was good at over 100.

After another 1000 miles, I am planning to go back and do the proper dyno.

Otherwise, love the bike - LOVE IT. Made it my own and very comfortable - apes are a must for tall riders on RKC.

Anyone had bad numbers in HP after the 103 work like me

[BamaHDRev]

I'm currently getting a 'modified' stage 2 kit installed on my new dyna. The dealership I work with is basically the excuse to have all the HD equipment for the owners and several of the servicemen to work on their drag bikes. So, I take them on their word with performance.

They steered me away from the kit as it was put together by HD. They said the cams are not the best for a 103 and that the SERT is less effective for low and midrange performance. I forget which cams they use, but I know they use the PowerCommander for mapping. They have told me that they can get easy 3 digits in torque, which you seem to have, but also bump the HP toward the upper 80's lower 90's.

When I get a complete readout on the kit they have assembled, I'll be sure to post the components. Also, they worked it so this kit is at the same price point as the one offered directly by harley. I also believe it involved a few other internal components, valve springs, etc.

[chris_lacey]

Tallroller, 70hp at 4500rpm, isn't too bad.

HP=Torque X RPM / 5252

So if your torque curve is fairly flat from 3000-5500 and you are still making near 100lb/ft of torque at 5000-5500 you are making about 99hp at 5000 rpm and 104hp at 5500. Not bad at all for a 103.

Of course we would need to see the actual torque numbers at those RPM to be sure, but my experience tells me that's about right for a 103.

Remember, your bike doesn't make 70HP, it makes 70HP at 4500rpm with 100lb.ft of torque. Big difference.

[Dave63]

You never mentioned what cams you had in it. If they're stock, (god...I hope not) then you're ahead of the game and worrying is way too premature.

If you're running an Andrews, Woods or other brand cams, most of those won't even start producing serious numbers until 4500 rpms to begin with....!!

Having a Dyno run and stopping at 4500 rpms is like paying for a hooker to give you a hand-job, and she leaves right after you drop your pants.....

Take it back after break in. Your numbers will be higher. You chould be closer to the 90-100+ HP mark at that time.

[gruss]

[quote=Dave63;151894]

If you're runing Wood, or " paying for a hooker " then your ahead of the game.

fixed it for ya Dave.....

[kerrycorcoran]

I love the knowledge this site has!!!!

[tallroller]

Originally Posted by Dave63

You never mentioned what cams you had in it. If they're stock, (god...I hope not) then you're ahead of the game and worrying is way too premature.

If you're running an Andrews, Woods or other brand cams, most of those won't even start producing serious numbers until 4500 rpms to begin with....!!

Having a Dyno run and stopping at 4500 rpms is like paying for a hooker to give you a hand-job, and she leaves right after you drop your pants.....

Take it back after break in. Your numbers will be higher. You chould be closer to the 90-100+ HP mark at that time.

They changed original cams with SE-255 and the dyno test stopped at 4250, yeah. I had another look at the graph. Max power 73.13 and max torque 101.69 The torque is over 100 from 2750 to 3500rpm and at 4000rpm the torque is at 96.

Totally got what you are saying Dave. But with the weather here, which royally blows big ones, I am looking at next year break-in time. I do ride in cold weather but very short rides, unless I trail my bike down or Daytona bike week or something

I'll see what happens at the next dyno after some mileage - I hope I get those numbers.

[tallroller]

Originally Posted by chris_lacey

Tallroller, 70hp at 4500rpm, isn't too bad.

HP=Torque X RPM / 5252

So if your torque curve is fairly flat from 3000-5500 and you are still making near 100lb/ft of torque at 5000-5500 you are making about 99hp at 5000 rpm and 104hp at 5500. Not bad at all for a 103.

Of course we would need to see the actual torque numbers at those RPM to be sure, but my experience tells me that's about right for a 103.

Remember, your bike doesn't make 70HP, it makes 70HP at 4500rpm with 100lb.ft of torque. Big difference.

My memorey was off a bit Chris but I restated the exact numbers in above post. I figured from the formula and with some break in time, I should be breaking 90HP. That's what I was after... 90-100 range.

The warranty convenience (done within 60 dys of purchase) and a great deal 15% off labour and parts = $2500 CAD Tx and all in, I went for it and the way it already feels ridin, it was worth it.

If it wasnt for the deal and the warranty, I would have prob gone with S&S 106 at least.

[serviceguy85]

All in all it depends on what your whole set-up is, if it is just the bolt up 103cu kit from hd, over all that is not bad numbers. Can you do better??? Yes, we have a 103 that is currently putting down 109hp, and 116ft tq. We did hd cyl. and higher compression pistons. Headwork included bigger valves and a port and polish job, we also decked the heads for slightly eve more compression just shy of 11:1, the bike is running a d and d fat cat, with a race tuner. The warrenty part is nice, but ultimately is up to the dealership of what they will also warrent with that. If you were to bring the bike back and say your clutch is gone, they pull it apart and see burnt discs and fibers, they will not warrent that, b/c if hd does request the parts back they will clearly see the rider spent to much time in the burn out pit or hard shifting and the dealer will not get paid back for that. Just something else to think about going hard on your bike all the time.