I like the sense of effortless accessible power, so torque spread is more important than power, but for the effortless part, I think it needs to be a litre+
BHP? Not bothered. Nm? Yes please and lots of it. Its not how fast you use your lever, its how big the lever is. Besides, I'm lazy.
Torque X RPM Engines do not make horsepower only torque. Horsepower is used as a measure of how much work an engine can do in a given time At least that's my (probably) misconception John
Torque = Force x Distance BHP is a little more problematic but its (T x rpm)/5252. I had to google it to remember it.
I remember that article well and regret having thrown it out. It was very informative. They fitted an R6 with the electronickery widgets to monitor how much HP was used on a ride. They had three people - a newbie, a seasoned journo, and an ex racer - all ride the same 40 mile route, and then looked at the results. The newbie never used more than about 45 HP. The journo made use of a max of about 80 HP on a couple of occasions but generally about 60 was enough, and only the racer hit max HP (about 125 IIRC) twice for about 1 or 2 seconds each time. He was well int to illegal speeds when he did. His average was obviously higher but even so they figured that 100 was certainly enough for most riders. Anything above that is just not used or needed. The reality is that it's pretty much impossible to use max HP on most bikes in first gear. 2nd gear flat out on most big bikes will break the speed limit anyway, so when are you realistically going to use all the ponies available on a sportsbike?. I bet most of us couldn't even use full power on track.
You are of course correct Torque X RPM will yield Watts which is the metric unit and roughly a BHP is 3/4 of a Kilowatt John
It took me a while too Finm to get ma heed around but its quite simple once it clicks. Horsepower is a construct used by engineers to size an engine for a given application or as bragging tool doon da boozer by lot of people who wouldn't know a horsepower from a half brick. Think about 2 engines with the same torque output, but one makes its torque at twice the RPM (Harley vs IL4??) So you hook these engines up to a hoist lifting say bricks or whatever. The engine producing the torque at twice the RPM has double the horsepower because it can hoist twice as many loads (or the same amount in half the time). Hence the race for higher RPM engines. I'm not an expert its just as I understand the concepts John
cool, i think. so for me then its all about the torque, probably explanes my love of the modern diesel jtd/jtdm, once you sus out how to drive em there quicker at least in my head anyhoo.
I like about 110 bhp. That's 63 from my 750 monster and 47 from my trailie big single.....though both produce good torque which, as already stated, is the more useful yardstick. Ok, I wouldn't mind just a tad more from the monster, but 70 would be about the max. Beyond that, I just wouldn't use any more. There's not a lot that I can't keep up with on the twisties with those levels of performance, and I avoid the flat out major trunk roads anyway. I agree very much with the earlier comment that light weight is more desirable than excessive power. And I much prefer not to have the complexities of four valves, water cooling, electronic injection etc which give the excessive power in the first place.
Big numbers are great. It is not about accessing the big number at 12k rpm: instead, it is the fact that at 6k rpm you have more. Few could use more than 120-130 HP on the road before getting into license losing territory. But if a bike only produces 130hp at 12k rpm, you end up having to wring its neck and ride erratically to make exciting progress. Personally, I like to use 130hp or 90lbft torque at 6k rpm as that makes an exciting road bike. That same bike will happen to make >175hp, but it is somewhat academic.
The 954 Blade makes about 130hp at 14-15k rpm and weighs about 165kg... But after riding an 1198, the 954 feels genuinely elephant slow. It's about how a bike makes it's power that equates to an exciting motor, or not.
I hear you, but is the kicker not that in the race for revolutions the power bands become relatively narrower? So for a given displacement, the higher power IL4 feels gutless low down and then hits the power band and launches you like a missile. Maybe now with the truly massive amounts of power these engines are making its not such an issue, I haven't rode an IL4 in a long time. Back in the day when the IL4s were leaving Brit and Italian stuff for dead hp wise, it tended to be an all or nothing experience. I dislike them intensely but a Harley off the line can feel like its ripping your arms out. Lower revving engines can be a lot more fun, but like everything else everybody's perception of what is a low revving engine is different. For me 8K is about right. I love the grunt on the 1098 and was pleasantly surprised when I tested one just how torquey off the line it was. To show what girl I am the rev lights on the dash remain brand new, never flashed once probably never will John
My old Le Mans has about 75bhp but it's a heavy old beast. When I got it it weighed in at about 230kg, but it now weighs somewhere around 200kg and is a completely different bike to ride, much more fun. But still slow. 75 ponies ain't enough.
Modern IL4s do offer very linear power/rpm characteristics. They certainly don't behave like 2-strokes with a 500rpm power band. But because IL4s rev so much higher than Vtwins, at 6krpm you are likely to be making significantly less than a similar twin of equivalent capacity. Hence why it's so easy to prefer Vtwins for the road, IL4s for the track (in general). Alternatively, you just pick a bigger capacity IL4 that gives bigger thrust down low, plus the power at the top end... Sadly big IL4 CC (1300-1400) comes at the penalty of weight and size. Ergo my K1300s produces good numbers (175hp, 105ftlbs) and is a great road bike for touring and all round duty, but it's 65kg heavier than my 1098R which still produces significantly higher numbers all over the place for any given rpm.
An interesting thread this lol. It just so happens that my 1098s was in the hands of Richard and Chris at Louigi Moto a few weeks ago. After Richard put right the stuff that was wrong with it from the previous owners, Chris did his stuff on the Dyno with the following results. First dyno run: Max Power 150.85 bhp @ 9727rpm, Max Torque 84.81 ft/lb @7925.3 rpm Last and mapped run: 158.54 bhp @9727.1 rpm, Max Torque 90.47 ft/lb @ 7891 rpm The whole riding experience is completely different now. Low end tractability around town is as smooth as a babies botty. Open her up and she propels you like a missile looking for a target. The torque though is what it's all about, that's why i ride these things..............................it's probably why most of us ride Ducati's. So for me the answer to the OP's question would be, 158 bhp and 90 ft/lb of Torque.
