I bought a low mileage Ducati ST3 late last year. It came with full service history, belts changed twice - etc. Loads of provenance. I have grown to dislike my ST3 due to its vibrations, which kick in during urban riding between 2,000 - 3,000RPM and is uncomfortable in traffic around town. The whole thing shakes like it's going to chuck the engine out the frame at times. The mirrors and clocks go ape. Since moving from Jap in line fours (Busa, R1's and similar) I've had a few RSV1000's, and few VTR1000 Firestorms, and a lovely SV1000. None of them did this Ducati vibrator trick. Is this vibration normal for an ST3?
You are not perhaps using to high a gear and letting the engine labour?I hated my GT1000 till I got used to the characteristics of a Ducati engine,
Ducatis don't tend to like much throttle under 3000 rpm. Dropping your gearing will help, as will tuning your motor. Is the ST3 carb or injection?
Yeah, dont ride below 3000 rpm and reduce the front chain sprocket to a 14 tooth one. That'll sort it. They dont like being ridden in town much actually.
90 degree v-twins shouldn't vibrate excessively. Unlike conventional twins, the engine configuration (and balance factor) means that the out of balance forces from one cylinder largely cancel out those from the other cylinder. If memory serves, the primary balance is better than an inline four cyl motor and nearly as good as a straight six !! I might suspect some other cause for the vibration you're experiencing ... worn main bearings, loose engine mountings or just simply uneven running at lower engine speeds.
I agree with the above. I've been playing around on my ST4. If you try and open it up from low revs it'll do it but it'll thump and vibrate. As the other guys said, drop a gear, or two, and push up the revs. Smoother, accelerates faster. Simples.
First things first, balance the injectors. I had an ST4 and agree with the previous comments that Dukes generally don't like low revs. However, it shouldn't be that rough, I'd take it to a reputable independent Ducati specialist and get it serviced properly if you don't feel up to it. It's not that difficult and I wouldn't necessarily trust a 'main stealer' to know what they're doing or to actually have done what they say!
Thanks for that. I've been on and around big bikes to understand the differences in riding styles, tried varying my riding style hoping to eliminate the problem and discounted that as a potential fault a little while ago. Never experienced anything quite like it since owning dozens of big bikes since 1976!...interesting about the flywheel though. Going for an oil and filter change later this afternoon, and I wonder if that will possibly make any difference?
Finding a half way decent one around here is an issue. There is one in Walton on Thames, and I used him when I had a previous RSV Mille. Bucking useless is my experience and would never trust him. Trades under about 5/6 different names. May use Cooperised in Feltham as I've known Ken for years, and although not a Duke specialist, I trust him and know his knowledge base. I also wouldn't trust a main stealer
Yep, I agree. I have owned 5 x 90 degree v twins previously and never known anything like this one. Something is wrong somewhere, probably along the lines of your suggestions?
Injectors could be the issue. May use super unleaded fuel, give it another thrash, ride it round town and see if that makes any difference as a quick cheap process of elimination to begin with. May be a fuel filter / fuel tank corrosion and or fuel starvation issue?
It's not so much a case of opening it up from low revs, which isn't my riding style that is the cause. As we all know, you have to go through the revs quickly to get where you're going, and it makes no difference. Like I mentioned in response to other threads, I'm an experienced rider of 5 x 90 degree v twins, and had no similar issues. Had about 6 x Triumph triples. Countless Jap in line fours. All since 1976 when I started with a 2 stroke Kettle
I was having similar problems with my ST4 and have traded it. Check all of the above of course but, before I took mine to trade it I checked it over and felt the chain was a bit tight. I eased it a bit and it rode really well on the way to the trader. It may be worth checking?? ATB
