Bimota Forum

[polyesterpig]

My bike has been down for a couple of years due to a valve guide going out and no spare time to sort it. Well Finally got my motor together and put it on a power commander Dyno. I wanted to see where I am at. It is a Bimota DB4ie, which I thought it had a Ducati 900ssie motor, but it has the Monster 900ie injectors and the 900ssie coils?

The motor had the heads ported, a Giannelli slip on exhaust, and the throttle body butterflies knife edged with the shafts milled flat. I also put on a Ducati performance 900ssie ecu knowing it was the closest choice. (currently no power commander installed)

I know every Dyno varies, so here are the results:

Max power 83.60 @ approx 8000rpm then slowly drops off.
Max torque 59.96 @ approx 6200rpm then slowly drops off.

I don't know if I was expecting more, since I didn't know what the stock numbers were?

The curve is pretty smooth for both hp & torque but it dips around 2500 rpm. It seems to be a running a little rich per the AFR graph in that area. I don't know if it needs a power commander map added? I think I will just ride it for a while and see what happens.

If I can figure out how to post the results, I will.
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2002 Cannondale E440
2003 Cannondale Super Mono 440
(3) 2003 Cannondale E440R
2010 Ducati Hypermotard evo SP
2000 Bimota DB4ie BiPosto

[V10LEE]

Very nice. What part of Cali you in?

[polyesterpig]

So Cal
_________________
2002 Cannondale E440
2003 Cannondale Super Mono 440
(3) 2003 Cannondale E440R
2010 Ducati Hypermotard evo SP
2000 Bimota DB4ie BiPosto

[deebee4]

Hmm, your max torque value seems quite low for a somewhat tuned fuel injected 904cc Ducati engine.

My carbed db4 (944cc kit etc) showed 96,2 Nm (71 lbft) @ 5.608 rpm on the dyno in March this year.

Seems like there's room for improvement in the fuel/air ratio in mid range.

On the dyno graphs you can see how crudely a carburettor regulates the fuel/air mixture. Altering a main jet influences more than just the top end. And needle positions too. So it's always a compromise, no perfection possible on carbed engines. You guys with the fi bikes are lucky to be able to regulate the mixture at any rpm.

Still, I like to hold on to the carbs, even if it was just for the flapping sound of the flat slides
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Track riding on a Bimota: FUN!

[polyesterpig]

I think the low torque figures are due to stock compression Pistons. Looks like you have a 944 piston kit installed. If it is a high compression piston kit, that would bump the torque up.
_________________
2002 Cannondale E440
2003 Cannondale Super Mono 440
(3) 2003 Cannondale E440R
2010 Ducati Hypermotard evo SP
2000 Bimota DB4ie BiPosto

[deebee4]

[macchiman]

I had my DB4ie dyno'd a few years back, also on a Dynojet. Standard engine with a modified map. Max power was 77.3 @ 8000rpm, max torque 55.7 ft-lbs @ 6000-6250 rpm.
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Bimota DB4ie
Ducati Paso 750
Aermacchi Ala Rossa 250
Parilla Wildcat 250
Neracar 1922 221

[Corona]

Bog standard with no tweaking


Compression was lower on the front cylinder but not by much

[polyesterpig]

http://www.ducati.ms/forums/attachments/supersport/476770d1417462651-dyno-results-900ie-db4ie-dyno-.pdf


http://www.ducati.ms/forums/attachments/supersport/477010d1417534784-dyno-results-900ie-bimota-dyno-run2.pdf
_________________
2002 Cannondale E440
2003 Cannondale Super Mono 440
(3) 2003 Cannondale E440R
2010 Ducati Hypermotard evo SP
2000 Bimota DB4ie BiPosto

[Corona]

That's close enough for me PP, a shot of chain lube or dyno calibration difference seems the only minor difference. The quest for more power on these engines always seems like your robbing peter to pay paul, I wouldn't want to sacrifice the driveabillity of the bike for a few hp more at the top unless I was track riding.