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Discussion Starter · #1 ·
What are the 998's true Hp & Tq numbers? and one with a good slip on Arrow exhaust. (I hear a lot of bs +- 30Hp)

Anything from 100hp to 130hp
 

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In the US, base 998's don't have a lot of power, we're talking 115 - 120rwhp at most. The technical reasoning behind the bike's low power delivery comes from the exhaust valve sizes, cam profiles and small diameter (50mm) exhaust headers. Ducati had some issues meeting sound requirements with the larger exhaust valves and headers, so they went with a smaller header and used a cam profile which delivered adequate power for the size of exhaust.

Unfortunately as a consequence, the 998's don't respond very well to aftermarket exhausts. Even the later generation 998R's with their higher lift cam profile, still prefer smaller 52 or 54mm exhausts, rather then the big-booming 57 or 62mm corse exhausts of the period. In Europe, Ducati was quick to release the 998S which had a greater lift and longer duration cam which wound up in the 998/999R of the cross-over generation (03/04) it wasn't until 2005 Ducati re-designed the engine again and made huge changes in the head including larger valves and greater lift cam's. The US got the 998S/R cam's in the Monster S4RS which was quite the treat as it was the last generation of standard testastretta's produced before Ducati moved into making the Testastretta Evo's.

So what should you expect with a base 998 with slip-on's? Not much more then 125rwhp and about 75lb torque. Throw some S/R cam's in there, you'll gain a bit with a full 54mm exhaust. I've seen 998's produce upwards of 130 - 135rwhp and about 80lb torque with the proper cam profiles and full exhausts. However, I was only there for dyno tuning and didn't measure the exhausts, so I can't tell you which ones they were using.

Funny anecdotal story, last weekend I was at a track day testing a friends bike and ran into someone who use to be one of my competitors back when I was racing a 749R. He simply came over, shook my hand and said "your bike was really fast, I was the guy you use to blow past on the straights". Just that pat on the back reminded me of all the 998's I'd blow past on the big long straights with my 749R. All of that to say… the 998's really aren't fast bikes. As I said in your other thread, they can be made competitive, but at a cost… Maybe a used 05/06 999R motor is in your future! LOL :D
 

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Discussion Starter · #3 ·
Thanks, I am building a ground up 748 frame with a 999 motor fraken Duc that I want to race or at least track. I figure that would be best to have a designated race bike.
 

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Can't really use a 748 frame with a 999 motor unfortunately. The vertical cylinder intake runs directly into the cross member of the frame. Some people cut that cross member out with a blow torch and re-weld it, but at that point, you're messing with the frame's rigidity. Plus, the swing arm pivot shaft is a larger diameter on the 999, so the engine won't rest on the shaft, this reduces strength of the rear end significantly. You can go the other way around and change the bearings on the swing arm + increase the hole size on the frame, but I'd be concerned about that because the 998 - 999 frame has more strength in that area.

Love the idea of building a franken Duc, I will be doing the same thing myself very soon. However, it's probably better to start with an appropriate frame, rather then trying to modify what you have to work. A 2001+ 748R or 998 frame will work fine for your desired outcome.
 

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The technical reasoning behind the bike's low power delivery comes from the exhaust valve sizes, cam profiles and small diameter (50mm) exhaust headers. :D
The US 998 has 45mm headers, 50mm headers only came on the deep sump models: Euro Bostrom, Bayliss and 998sFE bikes.
 

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The US 998 has 45mm headers, 50mm headers only came on the deep sump models: Euro Bostrom, Bayliss and 998sFE bikes.
Are you sure about that? The book I have says 50mm headers on all the 998's, though the US model's may not have been counted for some reason. I can't imagine them running 45mm headers, that's TINY!!!!
 

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Can't really use a 748 frame with a 999 motor unfortunately. The vertical cylinder intake runs directly into the cross member of the frame. Some people cut that cross member out with a blow torch and re-weld it, but at that point, you're messing with the frame's rigidity. Plus, the swing arm pivot shaft is a larger diameter on the 999, so the engine won't rest on the shaft, this reduces strength of the rear end significantly. You can go the other way around and change the bearings on the swing arm + increase the hole size on the frame, but I'd be concerned about that because the 998 - 999 frame has more strength in that area.

Love the idea of building a franken Duc, I will be doing the same thing myself very soon. However, it's probably better to start with an appropriate frame, rather then trying to modify what you have to work. A 2001+ 748R or 998 frame will work fine for your desired outcome.
you are completely wrong i have a 2000 748 with a 999r motor and it bolts right up with out any mods to the frame, the only things he needs to fabricate are the air box and exhaust just need to be mod
 

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Here are a few pics so you won't be mislead anymore by tuned, the bike now runs with all the 999 electronics and a Microtec I'll post a video later on or tomorrow Vehicle Motor vehicle Auto part Automotive tire Car Vehicle Auto part Engine Motor vehicle Car Auto part Vehicle Engine Car Bicycle part Land vehicle Vehicle Motorcycle Motor vehicle Automotive tire Land vehicle Vehicle Motorcycle Motor vehicle Car
 

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you are completely wrong i have a 2000 748 with a 999r motor and it bolts right up with out any mods to the frame, the only things he needs to fabricate are the air box and exhaust just need to be mod
I have no idea how you did this without some serious fab work. The vertical cylinder intake boot barely fit's as it is, when you lower the engine (the testastretta has a shorter head) the boot winds uo being lower in the frame, obstructed by the cross member.

Put the 999 throttle bodies on it… they will run right into that cross member!!!!
 

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I have no idea how you did this without some serious fab work. The vertical cylinder intake boot barely fit's as it is, when you lower the engine (the testastretta has a shorter head) the boot winds uo being lower in the frame, obstructed by the cross member.
look at the pics there was no fab work need it the motor bolts right up, stop making assumptions when you clearly don't have the answer to his question and totally misleading the guy,here is a video of the bike start up now the bike is tuned and made 140 to the back tire with a 45/50mm exhaust

 

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Show me the pictures of the throttle bodies mounted onto the engine without the airbox.

Ohh and I've tried this before and couldn't make any of it fit.
 

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I don't have pics with out the air box, but I could assure u the frame wasn't cut or modified, the throttle body was trim a bit but any one could see that when is getting mounted, the other route is use 998 electronics since the throttle body's fit better Engine Auto part Vehicle Car Fuel line Vehicle Auto part Motor vehicle Engine Car Auto part Carburetor Automotive lighting Engine Vehicle
 

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I see what you did, you cut the throttle body cross brace so it wouldn't be in the way. I still don't quite see how the throttle cable interface has enough clearance to work properly.

I never got far enough to bother, the pivot hole is smaller on the older frames (we were working with a 99'), after we noticed the throttle bodies hit the cross member AND we needed to bore out the pivot shaft hole, we gave up. I thought the throttle bodies couldn't push on, but then again we were working with 998 components which are a bit shallower. Looks like the 749/999 components fit a lot better, all be it, with a heavily modified system.
 
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