Ducati Monster Forum

I have  a Carbed M750 and an S4, i love both bikes but the riding technique is so different the M750 can be flicked through bends so easy on a tight line with just a hint of handlebar and footrest pressure and a little hip into the gas tank.

The S4 is completely different due to its greater C of G height and weight not to mention power it needs lots of aggressive counter steer and gearbox inputs ,footrest and tank nudges do nothing  for it . The bike prefers  the rider weight hung out round bend  it does not hold a tight line or flick around as well as the M750,even though it supposedly has the superior spec suspension.

i have spent ages trying to make the S4 handle as well as the 750 but its a different beast.

this is not a criticism of the S4 its just different but still fun.

jerry the Monsterman

and how do you find 2 vs. 4 valves - does that alter your cornering, throttle maintenance being more important on the 2v do to the larger amounts of engine compression?

The 2 valver is a more on off power u  really  and abuse it the engine braking is very sharp throttle can be kept hard on in corners or trailed easily the 4 valver is trickier u must slow more into corners ,trail the rear brake a touch and feed in the power smoothly  so it does not shake off line both bike like a lot of front end bias and the S4 is not so easy to set up as the front end cannot be dropped much  or it interfere with the radiator and the rear linkage is a lot more difficult to raise ride height ,I want to raise the S4 rear by 10mm ride height .the S4 power is much greater but it is smoother M750 =72 Bhp S4 now 115 Bhp

Jerry

Having ridden my carbie 900s and an S4R, I would have to say that I still prefer the throttle response delivered by carb'd motors.  I'm less affected by driveline lash, since the 0-5% throttle opening "crack" is much more smooth on a carbie than an FI motor.  I found the S4R much more on/off than my 900 for that reason.  I can't comment at all on handling, since my bike's suspension is set up well and the S4R's suspension was... weird.  The front and rear definitely weren't returning at the same rate, so I have no idea what was going on.  It also may have had a goofy map, causing more throttle response quirks. 

My S4 EFI has a great PC3 map that is not clitchy ...I think the biggest reason for quick flick turning is due to the big 180 rear tyre on the s4 compared to the 160 on the 750 and there is nothing one can do about that .

how about tire profile, that could explain the cornering as well ?

just a guess !

Very good point!  The 750 has a midget skinny tire compared to the S4R.  Also, the different rubber you're running will also make a huge difference.  On my SV, I have Pirelli Super Corsas and on my Monster I have Pilot Roads.  Two completely different sets of rubber for two very different purposes, and definitely different feel.  My Monster feels like a bit of a pig compared to the SV for that reason. 

If that's the case, then that's likely responsible for a great deal of the difference described by the OP.

And the only way to get M750 feel into the MS4 will be to find a way to fit narrower rubber.

Amazing what we've been convinced to put up with for the sake of  having too much rear grip.  [bang]

'Course, no bike ever got shunned in the showroom because its back tyre was too big.

I have tried Michelin Pilot Sports , Metzler Mez6 and Bridgestone Battlax  all give same result , next time i will try Pirrelli diablo corsa  but methinks its the fat tyre that make the difference ... i am going to raise the rear ride height another 10mm which will help , but i already use a completely riding technique which fits the S4.

I have ridden some friends Harley chops with super fat rears tyre 200 250 300 and they do not like going round corners , best tyre size for handling on the HD#s is 160,  but it does not look as sexy. Fashion over funtion on the customs but the S4 needs the grip of the 180 for the power.

jerry

If you got money, try lighter wheels...

The faster you ride (and lets face it, the S4 can go faster), the more the spinning parts try to keep you upright.

The earlier S4 Monsters definitely weren't the best handlers out there.  When compared to their 2v siblings (of any displacement) the 4v S4 always seemed a bit "truckish" in its handling manners.  However, since going to the S4RS Testastretta, Ducati gave it a new frame with different geometry (and of course sexy Ohlins suspension) and the results are nothing short of stunning.  My '08 Tricolore is every bit as flickable as any bike I've ever ridden, and way better than the earlier S4.  A buddy of mine has done everything imaginable to get his S4 into a flickable state, with all manner of suspension tweaks and outright replacement of components - all of which helped, but only to a point.  If you want a 4v Monster that really rails, you'll have to step up to a newer model.  And the other bonus, the Testastretta rocks!

I will get the S4 perfect , the front end is the weak point and I plan to revalve the forks .

changing the bike is not an option in Thailand it would cost $30,000 for an S4r here. any ways i now love th S4 i have put my energies and soul into getting right and i never give up .

BST's! and an Ohlins UES kit or Traxxion AK-20's!

Good luck on that project.  I don't believe you'll achieve true S4 nirvana without altering the basic geometry of the frame.  I've already sampled S4s with Ohlins and all manner of trick bits on them, but the geometry and weight placement is somewhat fixed and they've all been only marginally better than the starting point.  The best I've felt so far had the rear ride height increased considerably, which helped sharpen the steering angle and gave it a bit quicker response to steering inputs.  After revalving the front end with Ohlins components it handled pretty decently, but a steering damper was a bit of a necessity when really railing into corners at speed on rough roads.  You'll get there, but don't expect it to ever feel like your carbie 750.  On the plus side, that 4v motor will always put a smile on your face when it lunges forward out of every corner.

Put a 190 on your S4.

Then when you go back to a 180 you'll feel like it's diving into corners with no effort at all.

 [thumbsup]

    Correct me if I'm wrong (I may be), but I always thought that the opposite would be true. Sure you can squeeze a 190 onto the OEM S4 rim, but you are doing just that; Squeezing it on. This would make the tire's center contact patch smaller + its leaned-over patch bigger (think of a "V" versus a "U"), thus making the 190 feel like it wants to dive in more than the 180 on the same rim. Of course if you ran a wider rim to accomodate the 190, then yeah, it would be a little more sluggish. Just throwin' it out there...  ???

    I noticed the same thing when riding my S4 compared to a friends carbie M750 though. That bike felt SO small + nimble compared to mine, and it probably had a lot to do w/the 160 versus the 180 rear tire. One thing that really seemed to help me though, was adding a set of clip-ons. The stock bar height on the S4 was a little too high for my liking, and I noticed that getting myself a bit more hunched over really made the bike handle closer to how I want it to. Ideally, I'd also like to raise the rear ride height, but it seems to be one of those things I talk about but will never actually get around to!!  :-\

   

Maybe it was b/c the center of the 190 was squared off, but when I switched to a 180 from a 190 on my S4 it felt a hell of a lot more nimble.

I will never be able to make my S4 handle a well as my M750 but thats not the point , the M750 is perfect in my eye but the S4 front end is crummy,its also a much higher C of G and less steering lock at slow speed.I just want to get it as good as possible and its the front forks that are the only fixiable limitation after all the other changes like ride height etc ..