I am now having to replace the clutch plates AGAIN on my V4S Corse. On average I’m getting 2000 Miles. Anyone else experienced this with the STM dry slipper clutch as fitted to the V4R , V4SP and V4 Superleggera as standard ???
2000 miles on the road. The roads are up in the Cairngorm mountains with very little Traffic Policing. JHP Racing have told me the mileage is normal for this type of “race” clutch if ridden hard. The bike has a gearbox quickshifter and “down blipper”. Using the gear down blipper expedites wear on the clutch. 2000 miles seems very low mileage. my 1098R Bayliss and 998S Bayliss both had dry clutches which used to last approx 4000 miles or more. Ducati have fitted the STM dry slipper clutch as standard to the V4R , V4SP and V4 Superleggera. I think there’s going to be quite a lot of PI55ED off Ducati V4 owners if we get only 2000 miles out of a clutch !!!!
Do you do the maintenance yourself? Do you have a set of vernier callipers? if so measure the depth of the last steel plate to the basket face here...with the clutch pack fully assembled. This is a quick process and can be done without even removing most covers. Now you will find a slight variation across baskets and different make pack but either measure it now when its "worn" and measure again with a new set of plates. on average you are looking for a depth of 5mm if it goes dow to 5.5mm then follow below. You will note that the steel plates are all 1.5mm. You can use a 2mm plate (even one from your 1098 etc) to regain .5mm and so on. It will get you a bit more life out of the friction plates.
Thanks Andy , very helpful. I will check the measurement. I have ordered the STM clutch tool so that I can lock the basket and do the maintenance myself going forward. EVR can supply a set of friction plates and steels that have been designed specifically to fit the V4 STM dry clutch. I’m going to give them a try to see if they last longer. The EVR clutch plate pack is tried and tested by the Moto Rapido race team in their V4R’s and the plate pack kit is a £120 saving on the STM kit if bought through a Ducati dealership. Is 2000 miles out of a set of plates normal life expectancy ? I ride the bike in a spirited way , but not like I’m on a race track. (Most of the time) If 2000 miles out of a clutch is normal for the dry slipper , then I will just have to accept it. A bit like accepting I only get 800 miles from the Pirelli Diablo Supercorsa V3 rear tyres. On the subject of tyres I’m now trying the Pirelli Diablo Rosso 4 , hoping they will also last longer.
800 miles from a rear? Thats not right. I'm not light on throttle and I get 2-3k road miles from my 1299. Unless of course, your utterly spanking it like a hoon from the off till the end. Which, I am not judging by the way.
At best , I’ve had 1500 miles from a Supercorsa V3 rear on my V4. That was the tyre on the bike from new so I took it easy for the first 600 miles until the bikes first service and oil change. The one that lasted only 800 miles was last Summer. I went on a number of “very spirited” rides on that particular tyre. I call it my personal record !! YES , I was spanking it full chat on that tyre. if I can get 2500 to 3000 miles out of the new Pirelli Rosso 4 , I will be a happy man
Ducati also offer a stiffer slipper spring for the STM. Depends on how much engine braking you like but it might (and I emphasise might) extend the friction plate life. Andy
Thanks Andy , I spoke to both JHP Racing and Moto Rapido on Monday about replacing the STM spring. The standard spring is 60 Kg , they can be supplied in 50 Kg and 70 Kg My thoughts are the same as yours Andy , increasing the secondary slipper spring force might extend the friction plate life. Both JHP and Moto Rapido were both quite adamant that increasing the spring force would only affect the clutch slip during down gearing and would have no effect on friction plate life. I’m on the fence in this. My logic is that the less the clutch slips , the less the friction plates will wear. Logic determined by the laws of physics. I’m no little Moto GP rider. I’m a heavy guy weighing 110 Kgs. I might buy the 70 Kg spring and give it a go. Cheers and thanks again
A bit disappointing that the Ducati dealership that installed the STM dry slipper clutch on my V4S didn’t inform me there were different rated springs available when I purchased the clutch conversion.
FYI I have the same conversion on my V4S track bike. 2000 track miles so far and it’s fine. I regularly eyeball the basket clearance too and give it a fingering for clunkyness. All good so far
According to the STM dry clutch installation instructions......."Depending on the model on which you are operating, fit the appropriate Belleville washer. For Panigale V4, fit the 70 kg Belleville washer (25). For Streetfighter, V4 fit the 50 kg Belleville washer (47*)." These are independant and inboard (behind the clutch plate pack) of the spring you mention, so I dont know if these might have a bearing on things, if say for example the SF washer was fitted in error.
A 60 Kg secondary spring is supplied as standard with the clutch kit 50 Kg or 70 Kg secondary springs can be purchased separately. 50 , 60 and 70 Kg secondary springs can be fitted in the STM slipper clutch for all models of V4. From the STM website : Primary Spring • pressure action on the DISC PACK through the pressure plate. • function of coil springs. Secondary spring • pressure action on the DRUM; • it is used to adjust the opening of the clutch during the anti-skid, then to adjust the engine brake. How springs work The primary and secondary springs are mounted in such a way as to guarantee a preload which generates an initial resilient spring force. How the primary spring works When the lever is actuated, the preloading position of the primary spring is varied and reduced. The spring returns an elastic force of contrast to the action of the lever. How the secondary spring works The torque generated by the rear wheel tends to raise the drum. The secondary spring is compressed with respect to the initial resting position and generates an elastic contrast force.
70 Kg secondary spring ordered. I have replaced the worn clutch friction plates and steels with a kit manufactured by EVR specifically for the V4 STM clutch. Had to buy the STM clutch tool to enable me to lock the basket and undo the clutch nut (190 nm torque). The clutch is back working and no longer slipping under hard acceleration. Thanks to everyone who offered me advice , much appreciated. Still awaiting delivery of the 70 Kg secondary spring.
