Query approved

IMO the IRON will have a massive wheelie inducing low end and will make speed faster in the lower revs itself and the pull that one experiences when accelerating will be more in the Iron. But the ST7 will make more speed in higher revs.

You won't have to rev the Iron much where as you will have to rev the ST7 to get out!


This is completely what I think and may be wrong. Experts please comment.

The power delivery is different. The one on the Iron 883 will be similar to a Bullet 500 CI(only replaced with more pulling power obviously)
The ST7 in comparison will be similar to a ZMA in nature(But only muuch faster). But the natures will be similar.

The fact that you have to rev the ST7 a bit higher to get into the power band has nothing to do with the wear and tear. The bike's engine is designed to be run at higher revs in the ST7's case. If you are thinking about the ST7 over the Iron, you have my full support(if it counts ) the ST7 is truly a delight to ride.

And it will at least have a tank range which is much more than the Iron. I mean, for a 12.5 litre tank, the fuel stops would be much more frequent than pee-pee stops when on a longish ride.
It also happens to have much superior Ground clearance which means you can enjoy more and worry about the speed-bumps and pot-holes less.

Also, if this interests you, since the torque on the ST7 peaks over 4.6k RPM, it might actually have more BHP than the Iron/Superlow. The Might was there because HD do not reveal Horsepower figures on their bikes. Only torque.

Max torque at lower revs is good for touring bikes. U get max pulling power from really low revs. U can carry more luggage and it is effortless to cruise.

Thanks Guys.

Ha ha Actually initially I thought of not mentioning bike names. I was worried discussion will go there There is a thread here discussing that http://www.xbhp.com/talkies/what-bik...osung-st7.html
But yes I am also leaning towards ST7

Thanks. hmm.. I think that also means IRon will go up the mountain more easily than ST7?

Not 'more easily' per se.. both have enough torque to climb a mountain with luggage mounted. However, the Iron will go up a slope better if there are no potholes / bad roads involved.

Depends ...whether its a hill climb race, or just a tour uphill

Today's level of tuning means that one cannot derive much facts from the Max Torque figures.
Specs sheets and real experience is much different guys.

A bike may have 60 NM Torque @ 7000 rpm, but it may have
12 NM @ 2000 rpm, OR
maybe 5 NM @ 2000 rpm OR
maybe 35 NM @ 2000 rpm, all dependent on tuning, technology and cc's.

The initial figure 60NM @ 7000 rpm is of no use for your analysis of the engine, if you ride at 2000 rpm generally.

What you can derive from Max Torque's rpm is your cruising requirement.

If you generally cruise on highways at a speed of 80 kmph, try finding a bike which makes 80 kmph in top gear at the rpm on which it produces maximum torque. In other words, you should be on your Max torque rpm for cruising, specially with baggage for maximum push, to the throttle's input.


If you commute more than touring, try getting a bike with least max torque rpm for quick traffic boosts.
Like Suzuki Zues which used to give 10 NM @ 3000 rpm only. Which means at this speed, its engine gives maximum buck for the throttle.

Thanks Samarth, makes lot of sense.

If the fuel capacity is your main concern, what would you pick between HD SuperLow and Hyosung ST7? Superlow has 17 ltr fuel tank and the proven 883 HD evolution V-twin. Whereas, the power delivery in ST7 is not very refined.
However, ST7 beats SuperLow in looks and ground clearance.

Fuel tank

It would be practical but sad to choose a bike because of its fuel tank capacity. Well, the 48 from HD, scares the daylights out of me- but I guess its users know what its worth and why they buy it.
The Irons have the alternative to buy a 17L tank, with its 'street' average of between 18-20 on the highways, one could comfortably ride from Mumbai to south of Pune (clean toilets and a McDonald's) about 180-190Km, which I think is fair for a bike of that size.
Any range less than that, really worries me enough not to buy.

KD

I dunnO whether this is correct

My observation 2 engines, no big modification from stock, Same cc, they produce peak power approximately in the ratio of their peak rpm

But the max torque figure is similar irrespective of the max rpM
If cc is the same

Can you make it more clear? I couldn't understand what you're saying...

You're saying 2 unmodified engines have same cc. Then..?

I will explain what i am saying with a small comparison:

3 totally different bikes.

Sr. No.	Particulars	Pulsar 220	RE CL 500	Ninja 250
1	Volume(Litres)	0.22	0.5	0.25
2	Max Power(PS)	21.04	27.5	33
3	@RPM/1000	8.5	5.25	11
4	2/ 1*3	11.25	10.48	12.00
5	Torque	19.12	41.3	22
6	5/ 1	86.91	82.60	88.00

Each bike is totally different from the other and being stock, they won't have any radical components to increase power as they have to conform to pollution norms.

So as per my observation, there is a direct relation between Max Power and (CC * Max RPM) but there is a direct relation between Max torque and CC only with Max RPM making no difference what-so-ever.

So is max torque related to cc only unlike max power which is related to both factors?