the beauty of a 749 is that because of it's short stroke you can safely spin it faster. I'd go with an overbore ...best of both worlds. Stroking is for V8's
two cents
I stroked a 748r. It made 119hp with basic head work. Im thinking the stroke added 3-4hp.. The bigger bore works much better as it helps the airflow (valves being shrouded by boresize)
go big bore dude...
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The base 749 has the same stroke as the 999. If you want a different stroke, just buy a used 749R motor. I say don't spend the money, buy a 999 motor and be done with it. In the long run, you'll save money because you can sell your old 749 motor for only a few bux less then buying a 999 motor.
it'll cost a lot to stroke it. the 749 and 999 have splined primary drive gears, so you'll either need a splined crank - 999, 1098 - or new primary drive gears too. all other motors have tapered primary drive gears.
capacity is just capacity really. i wouldn't read too much into the "short stroke revs faster" bit. the 999 are rev limited to 10,500 with std or ti rods, the 749 limited to 11,000 and the shorter stroke 749r is limited to about 11,250. none of them rev high, and that'll only damage the collets anyway.
it's easier to go to a larger bore than split the motor and stroke it. easier again to just fit a 999 motor. probably cheaper too. but i don't imagine a 749 motor is very easy to sell.
if it had run the big ends and you needed to recrank it, that's another story. but it'll still be more expensive than replacing the motor. and you're moving away from the std capacities so the need for some custom tuning is greater.
you'd need some custom pistons to run a st3 crank - it's got 12.7mm more stroke, so the pistons need to be 6.35mm or so shorter and it might still pull them too far out of the bottom of the bore. i don't think raising the cylinders 6mm would really work.
but if you want to do it, go ahead. that's part of the fun.
stroke on a base 749 is about 5mm shorter than that of a 999.
Woops, I see my confusion... the 999R has the same stroke as the base 749's. I thought the 999R had the same stroke as the base 999's. The 749R still has a shorter stroke then all of them, which is quite interesting. I thought the 748R had a shorter stroke, it sure as hell doesn't...
Brad, i read on your notebook where you used the big bore kit on a 749, think this will probably be the way to go... and as it is a track bike, doesn't make sense to get all experimental and throw a bucket of money at it...
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Instead of the 916 crank could you use a 999 crank? Stroking a base 749 to an 808cc. Rods and such should still be fine. Keep in mind I'm new to Ducati so I could be way off. THoughts?
I highly recommend the 924 kit and the supplier. Ducshop
easy to install ..nice parts ..and turns the 749 into a wheely monster .
check out Brad black's Moto one site for instructions .
Last edited by seespotweld; 12-01-2008 at 06:01 PM.
Reason: spelling
Honestly the way prices for the 999 have fallen in the past two years you could unload your 749 and buy an '05 999 for less than the cost/headache of building some one off hot-rod 749 that you won't get one penny extra out of when you go to sell it someday.
The price difference between a 749 and 999 is very small.
749 Stroker
Linear Mode
