Hey guys. Here it is the dyno chart you have all been asking for. I added the new Daytona Twin Tech TC88A to my Sporty today, and after an hour on the dyno, I am a little dissapointed I can't seem to break 100hp at the wheel. The other thing that sucks is there is some sort of safety feature on '04 and up bikes that shuts down the power. When trying for only 2 sucessive runs, one run would be mid-90s and the next run would be high 70s. So we would shut off the bike, let it cool, and go again.

Anyway, we set the ignition at 2 and 7, with a 165 main jet. That gave us the best reading which was the 97.4/80.9 you see here. The bottom graph is my bike as an 883, stage 1, before we did the 1250 kit. I can't say I am dissapointed because the bike is running amazing, and is just flat out fast and awesome to ride. And going from 46.6hp to 97.4 is HUGE ! I just wish I could brag that I hit the magic 100 mark. I am pretty happy about that torque curve too. At least I can say it is at least 110 at the crank. ;)

As a reminder the bike is an 883-1250 and has Stage 3 XB heads, Axtell Nikasil Cyl, SE .536 cams, Mikuni HSR42 carb, 165 MJ, Daytona Twin Tec TC88A adjustible ignition, Bassani Road Rage 2-1, and a Forcewinder intake.

Anyway, and suggestions, comments or questions are welcome.

--Sean

97.4rwhp!

That's great! Well, they always say "The power is in the heads" ... And your bike sure does put out some nice numbers. So close to that 100 HP too. Now what ya going to do?

It's at [least] 110 at the crank. No doubt about it.

Nice numbers,
Ron

That's pretty sweet even if you haven't broke the 100hp mark yet.:D

Your losing power in your exhaust. I have a nasty set of drag pipes that are cut off at the magic 30" mark. They'll get you over 100. Wanna buy them cheap? Send me an e-mail. gwcrim@yahoo.com

Can you remove the baffle from the 2-1? That might do it too.

Exhaust is VERY critical to HP numbers. Though drag pipes suck for street riding, they're king on the dyno.

I would have to agree with crim. If you want to get thos really high HP numbers you'll need an open exhaust. I also think I'm correct in saying that that will hurt lower enf tourque numbers at the same time???

No biggy. Thos guys can mix and match graphs for you. Stuff some rags in the exhaust for one run for big tourque, then use the drag pipes for another and just mix and match the graph to show all your buddies!

But really, I think I would get slapped by some of the guys I work with for complaining about "only" 97+ rwhp. That is awsome and that bike should ride like a bullet!

I should have removed the baffle for shits and giggle, but man do I like that torque curve. Like I said, I am not unhappy...just hoping to hit 100. Ya think I'm close enough to just claim it? ;)

--Sean

Hey they way I was taught in engineering school you got 100!!!

WOW!



Congrats on those impresive numbers!

When my bike grows up, it wants to be just like yours.

I should have removed the baffle for shits and giggle, but man do I like that torque curve. Like I said, I am not unhappy...just hoping to hit 100. Ya think I'm close enough to just claim it? ;)

--Sean

Hell, I'd say it's your!!!! :D Great Numbers!!!! :clap :clap :clap :clap

Pull the baffles....run a dyno pull, break 100! Put the baffles back in for great street riding...KEEP THE DYNO SHEET FOREVER!

Over 97...that's like an "A", right? And a 100 is and "A" too. So I'd say you got 100.

A couple of thing I noticed about your graph is that your torque curve peaked a little lower than I thought it should with the .536 cams and those stage 3 heads. Meaning that the exhaust is more restrictive than I would have thought it should be for that combination, although I do not know much about that exhaust. Drag pipes or pulling the baffles will do exactly what the others said and you will have over 100 hp. Another trick would be to pull the air filter, or better yet do a head to head comparison between the Forcewinder and the SE filter. BTW, did you do the modification to the float bowl vent on the inside of the Forcewinder??? If not, PM me and I'll send you a link that will show you the details. Does your dyno sheet have the air fuel ratios? That would help to show if there is an over rich or lean condition in the upper rpms.

BTW, 97+ HP is nothing to frown about. CONGRATS and I'm sure you are only a few tweaks away from breaking 100 and still having a good torque curve.

Shu, can you explain why his torques dips and then goes back up. I have never seen a dyno sheet where the torques comes back up AFTER the 5252HP crossover point? I know about the dips in the 2-3K range. I thought it a bit odd. Just curious if you have any clue.

Shu, could you please post the mod to the float bowl vent inside the forcewinder. I have a forcewinder and would like to see how to do this. Also can you please tell me how much this will help my performance? Or where I will benifit or not benifit from doing this. I am very interested in knowing this. :smoke

Thanks Shu. I did not do the modification, so any tips would be great. I think i might try a run in the future with the baffles pulled just for shits and giggles. Also, we did several needle changes and got the AFR pretty decent, although it isn't perfectally flat. Also, we did pull the aircleaner for the runs.

Barry, no idea, I was just happy it was flat, especially compared to the Stage 1 with the 2-2 where there is a HUGE dip (this dyno doesn't show it).

--Sean

... let it cool, and go again.


But are you dynoing the bike statically and without a powerfull fan to flow air against the cylinders?
Are you sure you'll not go to brake your engine?

On the road the wind and lot of air helps the engine to dissipate heat. But on a dyno who refresh your engine?

I think 100bhp are something awesome.
If you want that 1 or 2 ponies more, to say "I've been able to break the wall", put some octane booster or buy some nitromethane from a car/aero model shop and add to you carburant. You'll see bigger numbers...

--
Mr. Mechano
Kawasaki ZRX1200 152HP
Soon (next week) XL1200C

It looks like I have several questions I seem to have failed to answer. The easy one is a link to the modification you NEED to make to your Forcewinder. Go to http://www.badweatherbikers.com/buell/messages/3842/11192.html?1050553596 and have a look and read around. This site does a great job of showing the mod and showing the gains in power from doing it (or losses if you do not).

Without air fuel readings and not hearing the bike on the dyno, it is hard to say for sure, but I would guess that the air fuel was either too lean or way too rich from about 4500 to 5500 rpms and then starts to clean itself up. OR since he hasn't made the change to the float bowl vent, it might be starving for fuel for a second or two. Again, with the air fuel data it would be easier to diagnose. It could also be a result of the advance curve on the module he was running.

I am really a lot more curious why the SE .536 lift cams had a torque peak of 4,000. I'd say that whatever is causing that dip has cost Sportsterspive a bunch of valuable power right around 4500 rpms. Could be the pipes, could be reversion, etc. When you ran it without the air cleaner, did you notice a bunch of fuel spray coming out of the carb throat while it was pulling on the dyno?

SportsterSpive, I notice you are running the Mikuni carb, so I am not sure the Forcewinder modifaction would be the same as the in the link I posted above. I'll ahve to look at the Mikuni setup and see if it would be prone to that problem.

But are you dynoing the bike statically and without a powerfull fan to flow air against the cylinders?
Are you sure you'll not go to brake your engine?


There were two big fans blowing against the engine. Shu, I will see if I can get the plot with the AFR in the next couple weeks.

--Sean

It looks like I have several questions I seem to have failed to answer. The easy one is a link to the modification you NEED to make to your Forcewinder. Go to http://www.badweatherbikers.com/buell/messages/3842/11192.html?1050553596 and have a look and read around. This site does a great job of showing the mod and showing the gains in power from doing it (or losses if you do not).


Following your link and searching with Google the name of the products reported into that forum I've found this:

http://www.wimmermachine.com/intakes-pop/in-ultrasucker.htm

From now I'll have horgasmic dreams... :wonderlan

--
Mr. Mechano

Whats the CR btw? If you want to garentee a consistent 100plus on the HP side may want to go to a Red shift 585v2 cam or switch out the stock hydraulic lifters from some hydrosolids(which will gain you a consistent 2-4hp. The .536 isnt the best grind IMO, even from SE. Great setup otherwise. Im sure that bike rides real strong.

Nightboy

CR is Compression Ratio!!

I think he knew that but was askin' what the cr is , not what is cr

I think he knew that but was askin' what the cr is , not what is crExactly. :clap

OOPS!!! :yikes

:urock LOL!

Aside from all the other suggestions which do seem to play into breaking the 100hp, what would be the effects of it being a california model? Aren't they specially modded? You do mention something about it having a power limiter or something that is shutting it down... The dyno runs seem quite suspicious, to go from 90 to 70? Something doesnt sound right.... Tell us though, how high can you get the front wheel off the ground? That's what really matters!!!