Ducati Sporting Club UK > Model Specific - Discussion, Technical Problems and Help > 999 / 749 > 749 front end?

[ttstu]

C'mon we're still waiting!

[keefer]

sag is the amount of movement at the rear end when the bike is on the paddock stand.
so if you stand at the back of the bike and lift up the rear (exhaust and seat)
you will notice that there is a small amount of travel, probably 10 - 15mm
the idea is to get it to travel less, ideally as others have mentioned about 5mm
you can achieve this by winding up the spring. (preload) making it firmer.
also try adjusting the ride height by a couple of turns as the ducatis are often set a bit kicked out from the factory.
this should give you a much better feel on the front.
just do it a bit at a time

[andyb]

Static sag is the amount of travel between the rear wheel and the frame between having no weight on it to the weight of the bike. When you add the rider you have loaded sag.

If you raise the bike on an abba stand rear wheel free, you take a measurement from a mark on the rear subframe virtually above the wheel spindle to the rear spindle, you then put the bike down onto its wheels, bounce the rear subframe to let it settle, then repeat the measurements.

What the difference is, is your static sag! 5-15mm is a starting point.

[HW]

Originally posted by keefer
sag is the amount of movement at the rear end when the bike is on the paddock stand.
so if you stand at the back of the bike and lift up the rear (exhaust and seat)
you will notice that there is a small amount of travel, probably 10 - 15mm
the idea is to get it to travel less, ideally as others have mentioned about 5mm
you can achieve this by winding up the spring. (preload) making it firmer.
also try adjusting the ride height by a couple of turns as the ducatis are often set a bit kicked out from the factory.
this should give you a much better feel on the front.
just do it a bit at a time

Just need to watch that if it's a mono with an aluminium rear subframe that you don't lift it using the exhaust.subframe because it will flex and give you a false measurement. Use 2 people further forward where the subframe joins the frame instead. On bipostos the subframe is steel and less likely to flex.

There is a good guide for 749/999 suspension setup here (with specifics for Showa vs Ohlins shocks)
http://www.section8superbike.com/749-999suspension.htm

[nathanhu]

sorry pedro i had to go and service something else for 30 mins

the effect of not enough rear spring preload on the bike is that the front steering angles( rake ) are increased ie like a chopper. this is because the rear of the bike squats to much with your weight acting on it.
to counteract this we ad more spring preload to the shock absorber ,this then pushes up/supports the rear of the bike against the added weight of the rider (the veriable in this equation) ................................
hic !!!!!! im drunk its time for bed

[V2 PETE]

front end felt great at 120mph at cadwell on sat , as was the rest of the bike . bit vague on the grass at 60mph though ! !

[HW]

Originally posted by V2 PETE
front end felt great at 120mph at cadwell on sat , as was the rest of the bike . bit vague on the grass at 60mph though ! !

So, what are you saying here? That the 749 is NOT suitable for Supermoto racing? Bummer ...

[pedro]

Originally posted by V2 PETE
front end felt great at 120mph at cadwell on sat , as was the rest of the bike . bit vague on the grass at 60mph though ! !

that was down to you having a ding-dong with steve was good to see

[butch890]

Pedro mate,fit the race kit-end of problem !!!!!!
front wheel only touches down at standstill !!!!
Butch

[JPM]

Need to get mine sorted, I feel for me the rear is too soft by far, seems to squat down and thus I guess would make the front feel vague as all the weight is shifting backwards