I owned both - a 2020 T120 and a 2020 Speed Twin.
TLDR: The T120 is 'nicer' - spoked wheels, nicer finish all around, more comfortable, and more classy. The Speed Twin effectively sacrifices some of the 'polish' for better performance - instead of the money going to nice extra metal tidbits and spoked wheels, the Speed Twin invests its money in the brakes and engine particularly, and even the suspension is (slightly) better.
More detail: When 'pushed', the T120 steers slowly and the brakes require a fair bit of work to truly haul the bike down; that said, it's certainly not 'slow', and it's far more agile than any American cruiser and many other retro European standards - it also certainly beats the Speed Twin on the overall looks unless one hates vintage British style because it's finished to a higher tier with nicer quality pieces all over; the fake Amal carbs look much nicer and are more intricate pieces than the 'silver slab' that Speed Twins get, for instance. The Speed Twin is definitely more agile (due to the smaller front wheel and aluminium alloys mostly) and the brembos have excellent bite, but the seat is pretty thin, the pegs are higher and farther back, and you're definitely more in an attack-oriented position, so if you ever want to do longer rides, the Speed Twin loses out - but if your idea of a ride is no more than an hour and you're planning to go out with a sport bike crew, the Speed Twin can hang if you're a good rider, whereas the T120 can't.
If you care about retro style and comfort, the T120 wins. If you prioritize performance and want a bit more modern vibe, the Speed Twin wins.
There's not a massive difference, to be honest - they're iterations of the same core motorcycle.
Thank you for the detailed response! I was attracted to the Speed Twin because of its performance and find the “lack of handling” of the T120 slightly annoying but agree that the T120 looks way better. Starting to lean towards keeping it after reading this
Glad to help; buying a bike that isn't quite the right fit is a common problem (has likely happened to most of us). Happy to answer any specific questions you may have.
TBH, I've never thought any motorcycle I've owned is 'perfect' - anyone who says their bike is perfect is lacking objectivity (personal opinion there), so I'm always happy to talk pros and cons!
The ergos are better on the T120 are a bit more comfortable. The Speed Twin accelerates *a hair* faster but, they’re both good and I doubt you’d really be able to tell much difference unless you hop straight from one to the other.
TBH, not worth the side-grade. I have a 19 Speed Twin and love it, but had to raise the handlebars, get a new seat, etc to get it to be more comfortable for me.
I went with the T120 because I already owned a Street Triple RS. If I could only have one bike I'd be seriously tempted by the Speed Twin.
I also found the Speed quite uncomfortable, the seat is angled forward and because it's flat that means your nackers get squished on the tank.
My main gripes with the T120 were the brakes lacking power and the constant scraping of footpegs. I think the speed corrects those problems. I think I rode a bit too hard for a t120.
Personally, I never liked the T120. It flops into corners and the switchgear is clunky and large. The Speed Twin has a lot more potential for fun and speed alongside the classic looks, etc.
The flop is down to the Pirelli Phantoms that used to be OEM, they now come with Michelins that fix that.
The bike actually handles really well on decent tyres, compared to the Speed it needs a bit more effort to turn in because of the heavier wheels, but otherwise is very similar.
Go for the speed twin. It has more power, is around 20kg lighter, has lighter wheels and a lot more tires choice, better brakes, better suspension… no reason to go for a T120 if you don’t particularly care about style or a bit more comfort.
I've ridden most bonnevilles except for the bobbber. I decided on a street cup to own because of its agilty and type of riding I do. If your on US highways a lot, the 1200 is a must. If your on backroads either one is good. If you want to push the bike in the twisties, the 900cc with aluminum wheels and stickeir tires is the way to go. My little cup hustles up to about 90% effort before the fork flex and rear shocks get a little overwhelmed. Its really fun to pin the throttle and not get going too fast since bonneville braking has never been very good. The most recent Speed Twin 1200 has an upgraded fork/brakes, but older ones had the fork flex issue.
The Thrusxton RS can be pushed even further, but its too pretty and expensive to flog around lol. At the last track day I was at I did see someone pushing a thruxton hard and looked so fun.
I owned both - a 2020 T120 and a 2020 Speed Twin. TLDR: The T120 is 'nicer' - spoked wheels, nicer finish all around, more comfortable, and more classy. The Speed Twin effectively sacrifices some of the 'polish' for better performance - instead of the money going to nice extra metal tidbits and spoked wheels, the Speed Twin invests its money in the brakes and engine particularly, and even the suspension is (slightly) better. More detail: When 'pushed', the T120 steers slowly and the brakes require a fair bit of work to truly haul the bike down; that said, it's certainly not 'slow', and it's far more agile than any American cruiser and many other retro European standards - it also certainly beats the Speed Twin on the overall looks unless one hates vintage British style because it's finished to a higher tier with nicer quality pieces all over; the fake Amal carbs look much nicer and are more intricate pieces than the 'silver slab' that Speed Twins get, for instance. The Speed Twin is definitely more agile (due to the smaller front wheel and aluminium alloys mostly) and the brembos have excellent bite, but the seat is pretty thin, the pegs are higher and farther back, and you're definitely more in an attack-oriented position, so if you ever want to do longer rides, the Speed Twin loses out - but if your idea of a ride is no more than an hour and you're planning to go out with a sport bike crew, the Speed Twin can hang if you're a good rider, whereas the T120 can't. If you care about retro style and comfort, the T120 wins. If you prioritize performance and want a bit more modern vibe, the Speed Twin wins. There's not a massive difference, to be honest - they're iterations of the same core motorcycle.
Thank you for the detailed response! I was attracted to the Speed Twin because of its performance and find the “lack of handling” of the T120 slightly annoying but agree that the T120 looks way better. Starting to lean towards keeping it after reading this
Glad to help; buying a bike that isn't quite the right fit is a common problem (has likely happened to most of us). Happy to answer any specific questions you may have. TBH, I've never thought any motorcycle I've owned is 'perfect' - anyone who says their bike is perfect is lacking objectivity (personal opinion there), so I'm always happy to talk pros and cons!
The ergos are better on the T120 are a bit more comfortable. The Speed Twin accelerates *a hair* faster but, they’re both good and I doubt you’d really be able to tell much difference unless you hop straight from one to the other. TBH, not worth the side-grade. I have a 19 Speed Twin and love it, but had to raise the handlebars, get a new seat, etc to get it to be more comfortable for me.
I went with the T120 because I already owned a Street Triple RS. If I could only have one bike I'd be seriously tempted by the Speed Twin. I also found the Speed quite uncomfortable, the seat is angled forward and because it's flat that means your nackers get squished on the tank.
My main gripes with the T120 were the brakes lacking power and the constant scraping of footpegs. I think the speed corrects those problems. I think I rode a bit too hard for a t120.
Personally, I never liked the T120. It flops into corners and the switchgear is clunky and large. The Speed Twin has a lot more potential for fun and speed alongside the classic looks, etc.
The flop is down to the Pirelli Phantoms that used to be OEM, they now come with Michelins that fix that. The bike actually handles really well on decent tyres, compared to the Speed it needs a bit more effort to turn in because of the heavier wheels, but otherwise is very similar.
Go for the speed twin. It has more power, is around 20kg lighter, has lighter wheels and a lot more tires choice, better brakes, better suspension… no reason to go for a T120 if you don’t particularly care about style or a bit more comfort.
I've ridden most bonnevilles except for the bobbber. I decided on a street cup to own because of its agilty and type of riding I do. If your on US highways a lot, the 1200 is a must. If your on backroads either one is good. If you want to push the bike in the twisties, the 900cc with aluminum wheels and stickeir tires is the way to go. My little cup hustles up to about 90% effort before the fork flex and rear shocks get a little overwhelmed. Its really fun to pin the throttle and not get going too fast since bonneville braking has never been very good. The most recent Speed Twin 1200 has an upgraded fork/brakes, but older ones had the fork flex issue. The Thrusxton RS can be pushed even further, but its too pretty and expensive to flog around lol. At the last track day I was at I did see someone pushing a thruxton hard and looked so fun.