I have recently aquired a 2016 Bonneville T120 - 5000 miles only, great bike, apart from the fueling at low speed in first or second gear. Having investigated on many forums, this appears to be a common problem and I have fitted a 'Power Plug' in order to improve matters. This has been partially successfull, but the bike still suffers from apparent poor fueling at low speeds, resulting in annoying snatching or surging and subsequent poor throttle control whilst in traffic or manouvering. Any other suggestions as potential cure/improvement would be welcome
David Bysh Welcome to the family. There was a topic on here were someone fitted little covers around the throttle nipples and apparently it smothes the throttle out and makes the bike run sweeter. Think it was on YouTube aswel. Someone should come along soon to rescue with the proper details. Do hit the upload a file button bottom right corner and show of the beastie to the inmates here in the asylum. Joe.
Changing the gearing {front 16t & rear 40t} will improve low speed manners and ease the wear on the clutch.
The Bonneville T120 certainly has the “roll off/roll on” problem. I have not been able to find a solution. I’ve tried a booster plug and it made little if any difference except lighten my pocket. It is my belief the throttle spacers used by Speed Twin to remove slack are not available for this model as the RH Switchcubes are different. The only imperfect solution is to be very, very gentle with the throttle and be prepared to use a bit of clutch. It’s taken me a year and just over 3,000 miles to learn how to do it. I think the best we can do is call it a “feature” and enjoy the good things about the bike.
Hi as @Trevor Austin says what you are experiencing is a feature of big twins. They are all lumpy at low speeds and I find feathering the clutch smooths it out..
Littleade - I’m not so sure the throttle spacer used in this clip will work as the RH switchcube on Bonnevilles is different. I therefore assume the internal gubbins of the Speed Twin/Ducati Panigale switchcube is also different. If it is the same, I’ll get one in an instant.
I’ve seen this. You’ll notice that the throttle housing body is separate from the switch gear, unlike the Bonneville T120. Now if someone will guarantee this will fit I’ll buy one.
The spacer kit works brilliantly on the Speed Twin, totally transforms the riding experience. Unfortunately the T120 uses a completely different set up and the kit doesn’t fit, not even close! I’ve tried the plug-in gadget and found it made a small difference, but in all honesty not enough to warrant the price tag. On later models using rain mode around town helps to smooth things out. Apart from that you just get used to feathering the throttle at low speeds.
Looked at other forums and people suggested turning off the traction control. Did this and the problem has disappeared.
You sir, are a genius. My 2020 Speedmaster is really Jerry around town. I turned off the traction control and it is as smooth as silk. Thanks for a great tip.
A great tip Dave. My 2020 Speedmaster was really jerky around town but turning off ttc has made it smooth as silk. Thanks!
I suffered with jerky throttle on my 2018 Speedmaster but as the years go by it's a lot better. I believe one big factor in the problem was strong engine braking on a new engine. To improve my riding experience I make sure throttle action is smooth by squirting WD40 between grip and handlebar, and I replaced clutch cable when it was getting less smooth. I also keep the drive chain slack within tolerance to minimise backlash from that. After I did the last service and got the throttle bodies balance to perfection, tickover is now smoother as is slow crawling through traffic. I did try turning off traction control when I saw it mentioned here but that made no difference to my riding experience.
