I own two motorcycles; a Thruxton 1200 R twin and a Honda Hornet 600 four. Factory spec power is identical to within half a horsepower in the Hornet's favour but the Thruxton has nearly twice as much torque. The former weighs about 235Kg wet including a full tank of fuel and the latter in the order of 198Kg. I weigh the same on both. Subjectively, all out acceleration is very similar on both bikes. As to be expected, the Thruxton pulls well from 2,000RPM whereas the Hornet needs 5,000RPM. The Triumph is all done by 7,500RPM and the Hornet by 13,000RPM with the limiter at 14,700RPM. No surprises there. The thing that has surprised me though is how much the Triumph will complain if I ask it to do anything at all under 2,000RPM (ch-ch-ch-ch-chug). That particular RPM really is an on-off switch since immediately from that point it will pull well. The Hornet however will pull silky smoothily from just 1,000 RPM in a high gear though admittedly not exactly accelerating more than glacially until about 1,800RPM. It is then linear to 5,000RPM, hardens at this point and becomes a guided missile from 6,000RPM. Is the Honda's far superior flexibility simply down to more firing pulses and lighter oscillating mass or is there more to it? It has a capacity deficit of 50%, is carburettored, devoid of ride by wire, and quite likely I expect that its camshaft lobe profile is more aggressive than the Triumph's - so I would expect the latter to be more supremely tractable to low RPM - but it isn't. By far.
Thanks for that, Andy. How did you have it remapped please? Power Commander with preloaded settings, Power Commander customised on a rolling road, or something else? I was led to believe the Thruxton map is locked to all but Triumph (such as when I had a new map installed along with V&H cans) and that it cannot be remapped (as opposed to piggy back or tricking how it sees sensors).
Thanks, Andy and for the "agree", Dozers Dad. Something to follow-up when the Thruxton's laid up for the winter.
The thruxton is a heavyweight boxer, two big pistons banging up and down slowly, with more cc's and more torque. Your hornet gets it power by being lightweight, small pistons fleeing up and down. The power comes from the pistons running at high speeds, but this means you'll not get the torque, due to less cc's. You get power by being big or fast, but you'll get more torque from bigger engine. Depends what you like, I like big v-twins and the way they produce their power and torque, but others prefer the smooth power of a 1050 triple. Up to you. V4 is the best way to make power and torque. That's why most Moto GP bikes use them. That's why Ducati now use a V4 for their panigale. You get smooth power and torque from a big engine. More pistons will allow smoother running at higher revs (natural harmonics and more stuff I don't understand or can explain). And then you throw firing orders into the mix !!! Screamers and big bang's using crank angle's!!! Can do clever things, try a big bang R1, very different inline 4 , litre bike.
I get all that, thanks MrOrange and the way the Thruxton makes effortless torque through 270 degree crank and twice the cubes was a significant component in my choosing the bike - but the way the way that any semblance of useful engine operation falls off a cliff, switch-like, below 2000RPM and protest steps in in its place is extreme. It will be interesting to see what I find if I do shell out the £300 that I see a remap will cost!
Have you had the bodies balanced? I know the sv 650 ran like a pig at low revs, if they were out of balance. Might be worth a try, and cheaper than ECU reprogramming.
Don’t forget torque is a straight measure of cylinder pressure whereas horsepower is a mathematical computation of torque cycles over time and hence how much ‘work’ an engine can do. A four at the same rpm has twice the firing cycle and is inherently smoother but normally aspirated multivalves tend to produce little torque at low rpm. The twin flywheel mass and counter rotation balance shaft etc., needs time to spin up ...... and hence differing characteristics. The biggest thing is the Honda needs to be kept on the cam to generate its power while torque from the twin can be wound on.....much as the Street Twin bhp figure belies the way it drives. ALL of them suffer the breathing difficulties of anti pollution kit. I well remember 650s becoming 750s and 850s with the same output as lead was removed from petrol and octane ratings tumbled. Cubes count!
It will be all down to just where in the RPM range the engines start to develop their torque and how much, as the old saying goes BHP is how fast you go, but torque is how quick you get there.
Is this your first big twin? Incidentally, I was speaking to an associate the other day, and told him I was riding a Tuono now. He said he'd borrowed one recently and absolutely hated it!!! Same as he hated Ducati's (old v-twin 1098's etc), horrible lumpy things. If I tell you he has 10 bikes in the garage, all of them Japanese, and most of them V4 & 4 IL engine (Hondas, fireblades, etc). Been riding these 4's all his time on bikes, just didn't know how to ride a big twin. Without having a shot on your Thruxton, wouldn't know if it had a problem, but I would guess, maybe your trying to ride it like a 4 ? Keep it above 2000 revs when dawdling through villages (only time I ride slow enough for mine to 'chug'), and just use the mid-range torque, short shift up and just enjoy that surge of torque. Your four will happily pull between 1000-2000, but your twin won't. Your twin won't rev up to 12,000 (mines does), so run around in that lovely big lump of twist available in the midrange.
All understood, thanks Callumity, and it is your "A four at the same rpm has twice the firing cycle and is inherently smoother but normally aspirated multivalves tend to produce little torque at low rpm" that was behind my original post; I would expect both to apply but in practice with these two bikes the former does, but the latter doesn't - simply because the Thuruxton protests so much that mechanical sympathy means I don't even try to run it at the lower RPM where it should still be producing meaningful torque. I think the train of thought Andy started and which you include too (emissions strangling) does likely have a large role in what I experience. It will likely be in some months' time (during the winter) but I will post back the outcome of a remap.
I've ridden many twins, thanks MrOrange, and don't try to ride the Thruxton like a four (written nicely, not as a put-down). My question only arose given that the cliff from 2000RPM and below is so abrupt. On-off. More than just a cam falling out of range. I have put many miles under the wheels of a G1200 RS. Admittedly a boxer twin rather than a parallel twin with 270 degree crank trying to emulate a 90 degree V-twin, but still two 600cc pistons pounding along. Whilst it still softens-off as expected, it will happily be asked to work well below 2000RPM such as trickling around town in a sociable manner. It does have two things I don't like though; the oscillating reaction at low RPM from being a boxer and a horrible "braaaaaaaaaap" exhaust note. None of the Thruxton's soul courtesy of that crank configuration. Oh, a third thing too; it is so tall that I have to slide off the saddle on to one foot when I stop! Even tip-toes don't reach!
Never putting anyone down, glad you took it as intended. We all know they drop off, but the way you describe, does make it sound like something more. Check the throttle body balance and then ecu flash, hopefully that will improve it.
There seems to be far more writing here than is necessary, it’s a 1200 twin that’s just the way they are
The old Honda 400-4 was utterly gutless at low rpm almost made a 250 Yamaha seem torquey until it came on cam......
My Daytona 675R, and GSXR1000,ZX10,ZX9,ZX7,Rd350lc,X7,FS1E, YZ,125,250,490, CR 500, Kx500 I’m not going to go any further they’re all different. That’s bikes guys. just like women. One mans poison is another mans cure!!! ,
All bikes have to be in the power band of the characteristics to the engine. Myself I prefer the twins style of power delivery, my MT 01 only makes 90 bhp but 115 foot pounds of torque making its power under 5k although I rev her harder(limiter at 5.5k) Twins from different engine makers are all different too, I had a Tuono which had the rev range of a 4 but pulled like a twin also my 865 Bonnie revs to 8k but without the shear grunt of the MT. Having not ridden a modern Truxton I can only say your twin is different again from others you have ridden and you need to have her in "her" sweet spot.
