Hi all.. Advice please. I own a Ducati Hypermotard 796 which I adore, however, while I am more than happy with its top end speed I would like it to be a bit more lively on acceleration if possible... I have a race ecu with termis and a de cat fitted.... And no I do not wish to buy a 1100 thanks... Would a change of front or rear sprocket make a difference? Many thanks Noods
Yep, smaller front sprocket should do the trick, or if you prefer, a larger rear sprocket, or both. I'd go for 1-tooth smaller front sprocket to start with.
If one tooth off the front isn't enough for you, you can always fit a bigger rear sprocket as well, but that may require an extra link in the chain.
Changing the gearing to make it accelerate quicker will mean you lose top end speed. If you want quicker acceleration with the same top speed then you'll need to improve performance further, or just buy an 1100!
Theoretical top speed you mean. Some bikes just won't rev out in top gear, like my old TL1000S, lowering the gearing slightly allowed it to rev out higher in top gear, and actually increased the terminal speed. And anyway, how often do you actually use top speed? Not as often as the lower rev range, I'll wager...
Fully agree, I have yet to have ducati that in top gear would get more then 70% of its safe rev-range (so not including red part on tacho). Going down in front is good enough mind you, if you start also upping the rear you will start loosing top end speed, saying that loosing 5mph for gain of stupid acceleration is OK in my book. That is my next step for 695 I rarely go over a ton on it and it will easy do 120 on 5th (6th is just such a waste of weight).
I've only ridden the 796 Hyper once in Italy during WDW and it was shit, so I've no idea what its top speed is or whether or not the OP gets there often as he does say "while I am more than happy with its top end speed" which is why I wanted to point out that changing the gearing would affect this. The 1100S Hyper has a 1.848:1 primary ratio, and the sixth gear is 24/28, so with the standard 15/42 sprockets and a 180/55x17 rear wheel you should get a terminal velocity of 128.9mph at the max power point of 7750rpm. My 1100S has often gone up to 134mph on the clocks, so it seems that the Hypers (if not just the 1100) is geared about right compared to the way over-geared sports bikes. If you changed the front sprocket on the 796 from a 15t to a 14t, you would reduce the top speed from 123.6mph down to 115.3mph - that's a noticeable difference. But never let the facts get in the way of a good argument :wink:
thought you had a 996?! Either that or try an 848. Had mine flat on limiter in top..pulled it no problem
hmm, wide open throttle in top plenty of times. 70% only? Must try lots harder, lots lots harder. I have never maxed out in top because I gear it correctly (for my riding styles/slowness) so it hits peak revs just AFTER my braking marker. Tell a lie though, the 600ss was on the limit on hangar straight silverstone for 10 laps - then it ate a piston circlip.
Ate a gearing commander, have we..? So tell me this, oh Oracle, how big or small is the rider? How windy is it? What direction is the wind blowing? Is the rider sat up or prone? Unfortunately your 'facts' don't take into account the prevailing weather and the general incompetence of humankind. And I've seen 140 on my old fuglystrada with 100cc less. But then I never did trust Italian speedos to provide the 'facts'...
I'm glad you highlighted the word "should" as it saved me the effort. The facts as stated are a pretty good indicator of what will happen if he changes his front sprocket and that's a decision for the OP to make, as he will know what speed he gets up to (the "I am more than happy with its top end speed" bit you're still ignoring) and whether the reduced top speed will be a factor in this decision. Of course, anyone with a more than a handful of functioning brain cells will know that taking into account the weather is a fool's errand as what happens on one day is not likely to be the same the next and therefore just adds noise to the results. Maybe there is some truth in the http://ducatiforum.co.uk/f18/university-degrees-18541/ thread!
not when we're going down hill bone boy! Whereupon it is written that there will be a shop selling pies at the bottom. Yae.
To see the results of different possibilities.....Gearing Commander: Motorcycle Speed, RPM, Chain & Sprockets Calculator
Again, it's only theory. Your numbers add up of course, but they fail to take in any practical considerations. If we were to take the numbers as literally as you clearly want us to, we could add 3 teeth to the front sprocket and go as fast as a Panigale. But as those of us with common sense know, it'll never pull the gearing and will end up much slower than it was to start with. Conversely, if we shorten the gearing it will drop the top speed, but that top speed will be more easily attained at any given time, and it'll get there quicker too. I've never ridden a 796, so do not know whether it feels overgeared or undergeared, but I'm willing to bet that the bike, if geared slightly lower, will feel faster to the OP in almost every practical application apart from head down on a motorway with a following wind. Do you disagree with that..?
I only own a SS750 ie but am guessing the performance is about the same. I dropped one at the front and it was like a new bike. Smoother at very low speed and pulling better to the max speed. In theory the max speed is less but with so little power available you need another mile of straight to gain the theoretical extra 5mph on the top end. I live in Lincolnshire so spend most of my riding life between 50 and 95 (kph obviously officer) so I gear my bike for the best riding experience possible. If I lived in the south with all the smog and motorways I would probably have gone up a tooth for comfortable cruising. Real life, a far better testing ground than Google
Exactly my point. Thanks Nobbi Doesn't work on all bikes, mind. I put a smaller front sprocket on my Triumph Sprint, and sure enough it accelerated well, but then there was no shortage of grunt to start with, and all it did was put a patch of vibration right at the speed I used the most, making the bike considerably less nice to ride.
Well 996 was not accelerating no more about 9k RPM mark on top speed, top gear. Frankly dropping a tooth at front would make it rev till about 11k at same conditions. No bikes come out of factory and allow revving to red line in top gear I would have to say. Sustained red lining at top speed would make the engine go pop faster with so gearing it so it stops safe of red line is common.