Depressing 748 DYNO run

Hi guys,

Ran my 2000 Ducati 748 for the first time last week on a Dynojet with results that didn't quite meet my expectations. It has a Termi half system, and a Ultimap UM211 chip- otherwise it's stock. Bike has 7800 miles. Wish I could post up the dyno sheet, but my camera isnt working, so this will have to suffice:

Max Power= 84@10,550
Max Torque= 46@8,700

Seems kinda low to me...anyone else? Running conditions were 58 degrees, humidity 59 percent- so the weather shouldn't have made a difference. I know every dyno is different, but??? Didn't opt for the $25 extra air/fuel chart that was offered BEFORE he ran it, but sure wish I had!

Also should mention that the HP/TQ lines were both fairly smooth, no significant dips in either one throughout the RPM range.

Do a search. We’ve had a few discussions on dyno's. Basically if you run it on a different dyno under the same condition you will get different results.

But that dose seem a bit low for the bike.

Ya, I know... but those numbers are a far stretch from the "median" I would hope to have from dyno'ing the bike on several different dynos. Wondering what I should look for to be the culprit- air/fuel ratio? anything else??

That's what a 748 makes with a slip and a chip.

Looks like every other 748 dyno run I've seen... you should be very happy! Now you know why you need to work so hard to keep up with 600's at the track.

Here's a link to a 748 that Brad black ran:
http://www.moto-one.com.au/per....html
Dunno if yours is a 'strada'...I'm not an SBK guy.

Seems you're a bit below what he showed, but comparing across dynos usually isn't satisfying, from what I've seen.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 900CR &raquo;</TD></TR><TR><TD CLASS="quote">That's what a 748 makes with a slip and a chip.

Looks like every other 748 dyno run I've seen... you should be very happy!</TD></TR></TABLE>

900CR- I've read alot of your posts, and I know you're nothing short of a database for Ducati info, but I'd have to say I'm not with you on this one... I've paid special attention to 748 dyno numbers over the past year since I've owned the bike, and the majority (it seems) pump out around
90+/-1hp. Cranking out 84hp means that I'm ~6hp off of that mark, and as we all know, 6hp is difficult to squeeze out of a motorcycle- especially a Ducati.
This makes me think something is off- I'm guessing it's the air/fuel, but I cringe at the thought of paying another $50, just to have the bike dyno'ed again for the air/fuel test to be done AND the $350 it will cost to have a custom tuning done.

Thanks for the link Speeddog! Made me feel worse... but thanks! lol

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Holliday &raquo;</TD></TR><TR><TD CLASS="quote">

I've paid special attention to 748 dyno numbers over the past year since I've owned the bike, and the majority (it seems) pump out around
90+/-1hp. Cranking out 84hp means that I'm ~6hp off of that mark, and as we all know, 6hp is difficult to squeeze out of a motorcycle- especially a Ducati.</TD></TR></TABLE>

Just going by what I've seen with my eyes at a local, (and very busy), dyno shop. Your expectations would be considered 'high'.

I'm really not trying to blow smoke up your skirt, or hurt anyone's feelings who swears they have a 98HP 748, but they just don't pull the stratospheric numbers sometimes posted... Dyno numbers are kinda like laptimes.

You can expect to see some variations between dyno's... Be happy your bike is pulling ~85HP... I'll bet the operator could have made 2-3 more runs and showed you a number closer to your expectations... Funny how Dynojet's work that way.


Save your money for gear and billet

Holliday,
Be happy with the 85Hp that you're getting from your stock 748.
I've done a run on my 853 & ONLY ended up with 96.4Hp. I was expecting(hoping) a little over 105 ... hahhahaha
Anyway ... a stock 748 is supposed to produce 75Kw (100Hp) AT THE CRANK ...!!!
If you only knock a (very) conservative 15% OFF the claimed crank figure, for drive train losses, you're doing well ...
Smile dude. Your bike's in fine form.

Your figures sound about right. We dyno-ed my 748 at my shop using our DynoJet 250i and got about 88hp. I have Arrow slip-ons and a PC III.

how many runs did they do? the first one is always rubbish, altho the peak doesn't usually change unless it's wheel spinning.

i run them until i get at least 2, usually 3 very much the same. so i do at least 3, most often 4, very occaisionally 5 runs for the start off combination. if you're doing +/- fuel runs then once you've got the consistant start every run for a specific combo will be almost identical. i often finish where i started just to check consistancy - been fine so far. if you stop and restart often you need a few runs to settle it down again.

if it's got a bad fuel filter or something like that you'll drop power pretty quickly.

Please bear in mind that there are a lot of little variations in the measuring technique- Dynos can't measure power directly; they measure the torque and the rotational speed to calculate the power according to the following formula:

Power (Hp) = {Torque (lbs.ft.) x RPM} / 5252

So if the dyno under-reads by 2 lbs ft, the error for the power reading will be:

Error = (2 * 10550)/5252 = 4 bhp.

I would suggest superimposing the old and new torque curves on top of each other. Doing this for the power curves tends to heighten any differences further up the range and mask differences further down the range. Using torque curves tells you more- if your torque is dropping off from say 8000 rpm more than before, you'll know more about your engine than from looking at the power figures.

Normal.

Just curious - what were you anticipating?

torque is a measurement, horsepower is a calculation. And I have persoanly seen a 748 with Sil motor slip ons, chip, and full dyno tune. push 97 hp on two different dynos (same bike)

My 748/870 Dyno'ed at 101. It has a half system and a FIM chip.

Heres a 748 that makes 106rwhp

Before you doubt it, read on.
http://www.visi.com/~moperfserv/748hc.htm

Nice

I got 84.9 peak HP at 10K on a Factory dyno (maybe equivilent to 100 HP on a Dynojet) with 800 cc Wiseco pistons, SPS cams, Carillo rods, Falicon crank, FIM chip, 50 mm SIL full exhaust, DP small tail-mounted crankcase breather box, BCM ported heads, and running Nutec gas - so 85 on a stock motor doesn't seem so bad.

Interestingly, Desmotorsport built a motor with the exact same mods as mine, and dynoed it at Factory - it made 10 more peak HP than mine, but with much less midrange. The only significant variable I can think of is the timing (which they set differently), so that might be something to play with if you want to get more on top and are willing to pay for it. (I left mine alone since I'd already bought a 996 motor to replace the 800)

If this is off base I apologies but I am just curious.

I am in Denver Colorado at about 8500 ft. and have a 2004 998S. It is stock with the exception of 45mm Termignoni CF slip ons and the ECU for them. Would anyone have any idea about what this should be putting out in the way of HP and TQ?

Ride Safe.
Marc