Tweety

I guess I'm gonna go ahead and be predictable too... You all might remember I had the same opinion as 8541hawk the last time...

Believe me, there is a big difference on the VTR from "opening the throttle" to really honest to god, pinning it open... It's the difference between "Driving miss Daisy" and a bucking bronco...

I have played around with gearing... And the end result I came up with was that first gear was useless if you lowered the gearing...

Now, I have done all the other stuff... Basically all of nath's list except light alu sprockets that I dislike... And a few more... Including lighter flywheel... So with ~120 @ the wheel, lighter everything, and lower gearing this thing turned into a monowheel... I'm actually back to stock gearing, but factoring in my 190/55 tire on the 6" CBR wheel I'm still almost 2% lower geared than stock... I am honestly considering going the other way for street riding...

Geek... Take a look at this excel file... It let's you calculate all the variables for the gearing and tire changes...

nath981

Discussion on this can go many ways according to personal values/preferences/functionality/etc., and everyone wants to believe that his opinion is correct and that includes me since i try to do the what is right. There are certain things i would change if i were touring at highway speeds, but not many. The only tour/highway changes would be to revert to taller gearing to reduce RPMs to save fuel, engine wear, and noise, and to longer wearing tires like pilot roads or similar for more uniform and longer tire wear.

Relative to the benefits of reduced unsprung weight for any vehicle and especially those that lean, I am firm. So even if I were to change the gearing to 16/41 with touring tires(and it would be the lightest available for sure), i.e., I would stay with quality 520 chain with a alum rear sprocket like AFAM or Supersprox. I would also stay with light weight wheels/rotors for highway/touring.

Skeptics of "light is right" in terms of unsprung weight need only do their own tests to enlighten themselves. Drastic is usually easier to discern. For example, on my semi, I once changed all 18 wheels from steel to alum, and all 18 tires from heavy full size to light weight low profiles. The difference was nothing short of unbelievable. Smooth over bumps, quiet, vastly improve stopping and acceleration, fuel savings that more than offset the costs of the wheels and tires, drive longer with less fatigue, better able to focus, and so on.

Replace all the heavy with light weight unsprung components at once and you will immediately know that light unsprung weight is nothing less than one of the greatest improvements you can make to your motorcycle's abilities because performance is magnified exponentially because of gyroscopic centrifugal characteristics.

In terms of gearing preferences, I love 15/44 for the kinds of riding I do, which is twisty rural roads, no straight roads except when unavoidable. haha. Lucky to live where I live. Acceleration, mostly regardless of gear, is crisp and immediate, and allows quick exit out of corners without a lot of the drama of gear changes which can add to traction/smoothness issues that can upset the chassis and reduce the attention equation. I like to stay between 5 and 7 thou RPMs and nullify engine braking with neutral throttle so as to minimize some of those factors which can upset things mid-turn. I like to do what I refer to as “rail” though corners, or at least to approximate what can be done with my XR650. Am I riding at 100% on public roads? Not even close to how I would ride if I didn’t have to be concerned with cops, oncoming traffic, or slamming into other hard obstacles. Do I go as fast as I can and still minimize calculated risks? No doubt.

In terms of whacking the throttle in first gear, start at 5000rpm, your ***** smashed into the tank, finger pressure on that left bar lever and your right boot resting on that little pedal down there. Now you’re ready for the green light, but remember not to abandon the clutch lever until you’re well into 3rd gear. haha

7moore7

I haven't tried aluminum sprockets from personal experience, but I would think that the benefits of the unsprung weight are outweighed by the quick wearing tendencies of aluminum. You're not saving nearly as much weight as you are by changing tires or wheels, especially since the mass is so close to the center of rotation.

I'm just conversing for the sake of exploring viewpoints, but any $ you would save in mileage would be lost due to replacing sprockets more often. Any performance gain wouldn't be noticeable except in a professional setting where a second lost is the difference between first and fifth place. I'm just having a hard time seeing the point of that level of effort to save weight on a bike that is 13 years old...

8541Hawk

Here is a simple question, what gear are you in while you do most of your riding (as you don't like to shift)?

nath981

well, if you make it to 68, then 13 may seem rather new.haha.......Seriously though. i know most think like you, but not me. I live in the now, always have, like I might die tonight. So if a 13 yr old bike is what I have and what I can afford, and as fun as a superhawk, then it is the latest and greatest to me. And when i like something i keep it. I don't care what it's worth in a blue book or what others think it's worth or gonna be tomorrow, if it does it for me, that's what counts.

The first alum sprocket i had was a vortex and it only lasted a couple thous miles, but this AFAM is showing no wear after three times that amt. If i were to look at my bike like you suggest, i would only change the oil every 10,000 miles and leave the chain and sprockets on until there were no teeth on it or the chain broke. I consider my 13 yr. old SH like a personal friend that has my life in its hands, and treat it with love and respect. Kinda like an airplane that could drop you out of the sky if you don't take care of it, and you don't have a parachute.

Anyway, quality alum sprockets and 520 chains are unbelievably tough compared to just a few years ago, and so wear is not an issue like it was, except for a cheap-*** vortex or similar.

In terms of the value of reducing unsprung weight, the chain and sprocket is the least expensive thing you can do, except for Power Pures. When my rotors wear a little more i'll be lookin for light weight replacements too. If you could exchange every unsprung component for its lightweight counterpart and then ride it for a while, you would be reluctant to let someone talk you out any piece of it. And if they did, you would notice the difference, especially if you rode the same roads repetitively, as in, minimize the variables.

Unsprung weight cannot be compared with weight anywhere else with the exceptions noted by Tweety(lightened and balanced flywheel or other spinning/reciprocating). Given the choice of 50lb after spring reduction vs a unsprung 10lb. reduction, I'll opt for the latter every time.

Not only are the inward components like rotors, sprockets, and chains spinning at very high velocities, but they are hitting bumps/irregularities in a gyroscopic plane and this is transmitted to the suspension. In fact, I consider it an integral part of the suspension. Yes, outward spinning weight is more noticeable, but inward has a significant affect on improving ride/stability and/or how much the forks/shocks have to respond to.

7moore7

Haha, I wasn't knocking your love of the Superhawk. And if you're into aluminum, it can't be all bad! I understand unsprung weight issues- as well as centripetal momentum. A weight loss of 5lbs that is 6 inches away from the center of rotation is much more effective than a weight loss of 5lbs that is 1 inch away from the center. So tires are a very good way to reduce weight as they are on the very outside of the rotation. Reducing spinning weight is why lightening the flywheels allows for quicker spinup too... You've said this already, and I appreciate your effort to reduce all weight below the shocks, but the thread was started based on quicker acceleration so I still have that in my head somewhat.

I'm not trying to put down your style- you have a system that you've worked out and anyone who thinks that much about their bike gets my respect

My arguments weren't to neglect your bike though, they were just that in my case, opting for a weight loss in the chain/sprockets isn't worth the costs associated with them. No matter how good aluminum can hold up, it will wear out faster if all other factors are equal. I would rather spend my money and efforts in other areas. I would like the drivetrain to last longer for the type of riding that I do... I dunno, maybe I should try aluminum and 520 before I go on, eh? lol

nath981

Well, since I'm now unofficially an ASStronaut. or if you prefer, a space cadet, and thus am required to travel at a high rate of fuel consumption, I need to wear a space suit, and yes, and it is a bit cumbersome. Since i like to "rail" through corners though, i've been intending to trade this rather stiff suit(and it stinks in here too) for an engineer's uniform, which will certainly afford much more maneuverability. But until I get to it, shifting is rather difficult and something to be minimized.

Beyond these constraints, I really don't like to shift in turns for the reasons stated earlier.

It may appear that i am writing a handbook on riding, the values of unsprung weight, or whatever i happen to be expounding about, but really i'm just expressing my beliefs based on my experiences over a life of riding and driving. I'm honest and am not afraid to make mistakes to learn. It would be nice if more of us felt the same. That said, I'm no stranger to adversity, so it's of no real consequence whatever people want to think about what I convey.

If you wish to imply that I don't like to shift for any other reason than I feel it is most prudent while negotiating a turn or series of turns, then delude yourself infinitely.

Hope that answers your dig, I mean your question?

8541Hawk

Someone have a persecution complex???

I asked, what I though, was a rather simple question..... What gear is the bike in when you are doing most of your riding? You are the one who said you don't like to shift but instead leave in one gear, I just asked which one that was....... damn.

nath981

Hope I'm worthy of the respect but I doubt it. haha

Anyway, like i said, get all the unsprung lightweight components you can afford, get your *** up there in the salt river canyon area and spin it up. Then let me hear you say that you'd be willing to go back to OEM; and if you do want to get rid of them. i got dibs on the lightweight galphers.

nath981

persecution complex? haha. that would be the least of my issues. I have serious problems that require serious medications, and i'm out now. you hear me!

archaicguy