Red Duke Rider

What would be the use or application for this (using the rear brake during acceleration)? CF I'll try to kill two birds with one stone in my reply here. 1. The phenomenen of the rear of a bike rising under acceleration is known as anti-squat. Read pages 79-83 of Andrew Trevitt's Sportbike Suspension Tuning for a more detailed explanation. 2. Use of the rear brake when accelerating: The best place I can think of this being an advantage is going through turn 11 at Road Atlanta under the bridge. Give the bike a little rear brake as you're going under the bridge (remember you're cresting a hill at the same time) and the bike will be more planted. Can't remember exactly why it works, but it's something I picked up at the Pridmore School there a few years ago. I do know the rear end won't feel so squirrely if you do this. RDR

Jay; I'm not sure if these measurements are coincidentally similar or not but to you question of why have adjustability, my rearset mounting brackets can be adjusted vertically while the footpegs and toe pieces can all be rotated as they are offset from the stem that goes into the anchor bracket (for the pegs) or the brake/shift lever arms. The amount of available adjustment is significant (to me) and it took awhile to dial in what was comfortable. The resulting measurement from the front axle is irrelevant (to me anyway) because this is where I am most consistently attached to the motorcycle; the position of each point of contact (foot peg; shift and brake toe pieces) is critical to work the foot controls effectively. Once I experienced adjustable rear sets on my track bike, I quickly followed with a set for my street bike. Kevin Hey RDR, I did find your correlation of interest BTW. It intrigues me as to why engineers do things the way they do, but more on that later... Kevin- when I got my "adjustable" rearsets, I basically put them on then trial fit them for where my knee digs into the slim part of the tank. It's not perfectly where I want it but it's close (I think it was a shifter issue as why I didn't go for those last few mm's). Is this the proper way to set them up? I've been fussing with the functionality part of my rearsets. When they were in the stock location, shifting seemed smooth. Now I have to make minute adjustments to get it right. On my last ride, my bike was recalcitrant to shift 2>3, the shifter wouldn't return. Do you think this is a setup issue, or is my tranny on the way out? I never had this before changing my rearsets from stock to aftermarket. My F4i's rearsets are Bohemian adjustable (they look very much like Satos). I have attached to the shifter the Sato RC-51 reverse shift arm so that it will clear the sproket cover and allow GP shift. It works great most of the time. But it was embarrasing to fiddle with the shifter on my 2-up last week (maybe she didn't notice?). How'd you know I was an engineer? I guess I started my quest to see if there was a significant difference between Brand S, Brand H, Brand Y, etc - it amazed me when the numbers were all coming in the same neighborhood. I couldn't agree with any of you more that minute adjustments to any of the controls on a motorcycle can make all the difference in the world. Moving a footpeg up/down/forward/back a half inch can probably have as dramatic effect in your "comfortabilty" (invented engineer word) as the rotation of your brake and clutch levers, relationship of gear shift lever to footpeg, etc. All of us have our own unique body dimesnsions. All of us have our particular quirks/likes/dislikes in how things are set up. I guess that's why we all have a choice between blondes, brunettes, and redheads. Maybe the ultimate answer on footpeg location is for someone to design a set of rear sets with an eccentric adjuster to get your peg position just right. Hmmmmmmmmm.............. I sense a winter project coming on.

Hadn't thought of it simply as a relationship, nice! To be crystal clear, 0% would be measuring from the front backwards, correct? That's correct Cobie. Assume the front axle to be the zero point then measure backwards from there. I'd love for a few folks to measure some pics and/or their bikes also to see if they don't come up with the same type of number. You need a straight on side shot of a bike to do it from a photograph. It blew my mind when I did it on about 7-8 bikes and the numbers were coming up so close together every time. Check the photo of Hayden's Honda over Pedrosa's Honda in Andy Ibbott's & Keith's book. That was one of the first two bikes I checked. I checked my VFR800 and it came in at 70.4%. RDR.

I've been asking myself this same question lately - trying to find out where footpegs should be. I sat down with a set of calipers and a calculator and studied many photographs of every type of sport bike and racing bike there is. Especially MotoGP bikes. I found it interesting that time after time, the distance from the front axle to the center of the footpeg is always in the range of 69.5 - 70.5% of the wheelbase. Try it yourself. I was surprised how consisent this dimesional ratio was.

I've been asking myself this same question lately - trying to find out where footpegs should be. I sat down with a set of calipers and a calculator and studied many photographs of every type of sport bike and racing bike there is. Especially MotoGP bikes. I found it interesting that time after time, the distance from the front axle to the center of the footpeg is always in the range of 69.5 - 70.5% of the wheelbase. Try it yourself. I was surprised how consisent this dimesional ratio was.

Here's a trick I used to free up/get rid of some of the stiction on my Honda that was a very low cost solution. When you have you forks apart for you next servicing, polish, and I do mean polish, you fork legs (I'm assuming they're just hard chromed coated). My favorite device is to use a Black and Decker Mouse type sander with a pad on it that resembles a Scotch Brite pad. Look around at Lowe's or Home Depot for them. Use SimiChrome, and spend about half an hour on each tube getting them to a mirror finish. Wipe all of the SimiChrome residue off with a rage with lacquer thinner. Then apply of coat of MacGuiars #21 Silicone Sealant on the chrome. Short of spending hundreds of dollars for titanium nitride coating or something similar, this will get them very slick and low friction. If you have a lot of stiction after doing this, I would investigate a binding issue.

Thought I would give an update to search for the proper spring(s) for my scooter. I purchased a copy of Andrew Trevitt's "Sportbike Suspension Tuning". He goes into a fair amount of detail about empirical methods for determing the correct spring rate(s). I have followed his advice to a "T" and couldn't be happier with the way my bike is handling now. I'm to the point now where I feel like I'm very close to the most ideal spring(s) for my bike. Luckily, as I mentioned earlier, I have found a much more reasonable source of shock springs for Penske shocks than the motorcycle suspension speciality shops. I've built up a nice inventory of springs (both front and rear) and after you've done it 4 or 5 times I've gotten to where I change either the shock spring or the fork springs in about 15 minutes. My next stop in my odyssey is to take a couple of days off from work, get me a place in the mountains where I like to ride (which luckily has a garage), and spend a couple of days testing the difference between a 1250 # spring and a 1300 # spring. Same with the forks - try 1.2's, then try 1.1's., etc. Keith himself writes an excellent prologue in the book he authored with Andy Ibbott about spring rates. Between the Trevitt book and the Ibbott/Code book, it's really got me in the ball park 10 times faster than posting on the internet. I'm an engineer by trade and I'm excited about finally coming up with an empirical method for determining correct spring rates. I want to go beyond just a recommendation from someone on the internet. I guess I'm one of the unique guys who enjoys wrenching on his bike just about as much as riding it. Sometimes it pays to go back to school (so to speak) and hit the books. I think all too often in today's world we let other people do our thinking for us instead of learning and figuring things out for ourselves.

lol You meant 10% of the gross, right? Definitely.

I searched a few weeks ago, and saw the books online (amazon). Cobie: I assume that Racer and I are going to get a 10% commission for any books we sell for you guys aren't we? RDR

Racer: Just went to Amazon.com and T1 and T2 are both there. http://www.amazon.com/s/ref=nb_ss_gw?url=s...p;x=15&y=10 RDR

Thank-you for bringing this book to my attention, Red. I've never heard of it before. I wonder why it isn't available here on the website in addition to Amazon.com. Ironically, I can't find the Twist of the Wrist books on Amazon.com. Great book! Literally study the pictures in detail. For instance, MotoGP riders do use fixed pegs, not folding pegs. An interesting picture in the book is a pic of Rossi's rear brake pedal. There is no adjustment on it what so ever. Why? Because it has been custom machined and fitted to Valentino and doesn't need to be adjusted. Eliminates all of the threaded links, nuts, etc. Keeps things light and simple. Don't know why it's not available on the website. I think the book is probably 75% Ibbott and 25% Keith. But as I said, Ibbott is a disciple (no pun intended) of Keith's and runs CSS in Europe and works with the MotoGP riders a lot. I can't sing the praises of this book enough. The most amazing thing is it's only $19.95 for a hard back book. If you're near any big city, T1, T2, and Soft Science can usually be found in Barnes & Ignoble and Borders.

Excellent description! You and I are in the same groove here. We're just using different wording.

To all regarding Pivot Steering: Another excellent and more up to date read on the matter is found in "Performance Riding Techniques: The MotoGP manual of track riding skills". This is a hard bound book written by Andy Ibbott and Keith Code. Andy Ibbott is Keith's "disciple" in Europe. From what I've been able to gather, he runs Keith's European operation(s). Andy and Keith both elaborate on peg weighting - which one to weight and which one not too. The book is one of the best bargains I have seen in a while. It has some excellent photography, it's hard back, and it's only $19.95 at Amazon.com. Keith does an individual prologue in the book on setting up your suspension. The book has some absolutley stunning photography. One picture that sticks out in my mind is the pass Rossi made on Gibernau a few years back when Rossi stuffed Gibernau big time. The photograph actually consists of an overlay of 6 or 7 photographs all taken from the same point showing how the pass was made in sequence. Maybe this book should be called Twist of the Wrist 2 1/2. Great book. Lots of detailed pics of MotoGP bikes and how they're set up. A photo of Hayden's bike directly over Pedrosa's bike so you can see all of the differences. Can't say enough good about the book. I can say that from what Ibbott and Code have written in the book, the MotoGP guys aren't putting all their weight on the inside peg. Going back to the Pivot Steering or Cross Steering discussion: Issac Newton or one of those early science wizards said that "for every action there is an equal and opposite reaction". The action of pushing on the left handlebar to turn left is reacted by your right foot pressing against the right peg. More and more I've got where I don't like the term or concept of peg weighting. In reality, it's peg pushing. Which peg are you pushing against for a given turn.

My 2 cents worth on pivot steering: I think Chapter 19 of Twist 2 is probably some of the most profound words KC has ever written. You probably won't get it the first time you read it, or not even the second. You may have to read it 4 or 5 times for it to sink in. Once it sinks in and you figure it out, it is as revolutionary a concept as counter steering is the first time you figure it out. Case in point: I read Twist 2 many times before I figured out what KC was trying to say (nobody said I was a fast learner). I own a basement full of bikes and just so happened to be on my Goldwing (of all things) one day and thought I would give the "Pivot or Cross Steering" a try. I tried it in a left hand turn. The bike flicked over so fast, so hard, I just about dislocated my left hip when my folding peg hit the pavement with such force and drove my thigh up into my hip. Conscious counter steering combined with conscious Pivot or Cross Steering will turn a bike so fast and so effortlessly it's unbelieveable. I have learned from Chapter 19 that I don't like to use the term of "weighting the pegs". What you're actually doing is pushing against one peg opposite the handlebar end you're pushing. A good example for you to think about. Some people say you should weight the inside peg and use a light touch on the handlebars. Do this experiment. Put your bike on a stand, remove the right peg, cross your arms across your chest, and see how much effort it takes to shift your body to the left. It can't be done without a lot of scooting around on the seat which would certainly upset the bike. Now put the peg back on, sit back on the bike with your arms crossed across your chest (i.e. simulating an extremely light touch on the bars). Shift your weight from side to side. See which peg you're pushing against when you move side to side. You push against the right peg to move left, push against the left peg to move right. Again, my 2 cents. I could be wrong.

On the VFR, not sure how high those are, seems more likely you could touch those down, might want to find the limit gently C I agree 100%.

Haven't touched my solid mounted pegs on my Duke II (I have some Woodcraft rear sets for an R1 that I modified to fit). I'm getting ready to install solid mounted pegs on my VFR because I like the "connected" feel so much. Just wanted to make sure I wasn't overlooking something.

I'd like the hear the pros and cons on this subject. I sure do like the feed back I get from solid mounted pegs but when you put one down it can be bad news.

I think Penske's are the best. I run one on every one of my bikes (Duke II, VFR8700, and Honda ST1300). There are a bunch of Penske dealers around or you can deal directly with Penske themselves (deal with Shane Sweigert at their PA offices). You'll be dealing with people in the good ole US of A that speak English BTW. One of the beauties of a Penske shock is that you can add on to it as your pocket book will allow. You can start off with the Sport shock which has rebound damping adjustment, length adjustment, and of course spring preload adjustment. Those run about $600. You can later add a remote reservoir with compression adjustment for a few hundred dollars more and finally build it up to a top of the line shock with the double compression adjustment (high and low speeds). Also, springs that fit Penske's are available from the motorcycle suspension shops for $99.95 for a Hyperco spring or do as I do and order your Hyperco spring from a race car suspension shop for $66.95 (Hoerr Racing Products - www.hprworld.com). Penske's can be switched from one bike to another simply by having the bottom shock attachment changed and the shock re-valved (and possibly a new shaft to change the shock length) for the new bike. If you ever decide to get rid of your bike you'll have no trouble selling a Penske on FleaBay.

Chapter 19 of Twist 2 is some of the most illuminating words ever written about riding a motorcycle around a curve. You may have to read it several times, contemplate your navel for a couple of days, and then re-read it again. It's a little heavy concept but once you grasp what Keith is saying in Chapter 19 it's significance rivals the importance of learning counter steering. I think Keith could teach an entire school or two just around the concept(s) in Chapter 19.

Thanks for the reply racer. Taking the spring off and on a Penske couldn't be any easier. What I plan to do is jack the bike up, take a measurement, then remove the shock spring, and using either a screw type jack or bottle jack, begin compressing the swingarm until the shock body just contacts the rubber bump stop. The difference will be the amount of shock travel (or more accurately, rear wheel travel). While I'm under there I'll also place a small tie wrap on the shock shaft to see how much travel I'm using. I'll do something similar with the fork. We all pretty well run a tie wrap on one of the fork legs to see how much travel we're using but how many of us have put a mark (probably a colored piece of electrical tape) to designate the point when the fork bottoms out? Forks don't travel until the bottom triple clamp hits the top of the slider on convential forks or the axle holder hits the fork tube on USD forks. They bottom out quite a few millimeters before then. How few of us mark the bottoming out point to see just how much of the actual amount of fork travel we're using? My racing days are long past me. Retired from competition years ago. Our choice in shocks back then was either S&W or Koni's. But I still like to ride hard and enjoy wrenching on my bikes when I'm not riding them. I'm an engineer by trade so I guess tinkering and improving things (and learning exactly how they work) is in my blood. Please don't interpret my previous post as a slam on TD. There are thousands of guys out there who swear by them. I'm in the small percentage who swear at them. Penske is a great company to deal with. I don't think people realize you can deal directly with them. They have a whole staff under Shane Sweigert who handle nothing but motorcycles. When you deal directly with Penske, you don't have to wait on them to "order" a shock or a part. They just whip one out. Penske has also starting sending Shane to races to offer racer support. Thanks again for your input.

Thanks for the inputs guys. Trevitt devotes a pretty large amount of ink to figuring out the spring selection process. To give you a little back ground (and being completely honest here), I have bought 3 Penske shocks from Traxxion for three different motorcycles I have owned. There was not a single one of them correct as they were shipped to me. The first exprience was a Penske shock I purchased from them for an SV650. It came with no half inch to 10 mm reduction collars and the manual told me how to set up the shock if I was running it on an Indy car at Pocono, Daytona, etc. It being my first Penske purchase and hearing so many rave reviews of them, I figured that was the way it was and to make do with it. Making a long story short, I wound up drilling out the shock bosses on my SV650 to accept a half inch bolt. It wasn't until later that I learned of the existence of the shock reduction bushings. The second shock I purchased from them was for my VFR800. It was shipped to me as a shock for a VFR750. A half inch too long. Had to send it back to be shortened. 1400# spring. My third Penske/Traxxion purchase was for my ST1300. The shock wouldn't even fit the bike let alone the spring was 300 # too soft. I went onto some ST1300 websites and learned that I had one of two choices: either grind some material from frame for the shock to fit or send it back and have them install a long top on it (apparently there is a standard top and a longer top for a Penske). By this point to say I'm burned out on Traxxion is an understatement. They are 3 for 3 with me on screw ups. That's after spending a couple of thousand dollars with them. Not exactly confidence inspiring to say the least. Therefore, I'm very leary of their recommendations. Out of desperation, I called Penske themselves. They told me to ship the shock for the VFR800 and the ST1300 to them and they would straighten the entire situation out. Took them about a week and they called and told me my shocks were ready. I asked what the damage was ($$$). $17.95 for shipping. No charge for the work they did at all including parts. They were more concerned with a satisfied customer. So I can't say enough good about Shane Sweigert and Cole at Penske Shocks in PA. Those guys are the best and do take care of you. I know I digress here, but that is why I don't trust Traxxion's recommendations but still think Penske shocks are the best there is and hence why I am trying to learn more of how to setup my bike than just having somebody tell me to run this spring because they said so. So far I have come up with two parameters that seem to apply to the correct spring rate: 1. Select a spring that requires the lest amount of pre-load to achieve the desired amount of static and dynamic sag. 2. Select a spring that is at least twice as long as the amount of shock travel to prevent spring binding (this applies to the shock spring). Luckily I have found a source for shock springs at very reasonable prices so I can do some experimenting: Hoerr Racing Products (www.hrpworld.com). Hoerr is a race car suspension dealer that sells Hyperco springs. A Hyperco spring is a Hyperco spring is a Hyperco spring. It doesn't matter if it's going on a motorcycle, an Indy car, a NASCAR, etc. Most motorcycle suspension shops sell Hyperco springs for $99.95. HRP sells them for $66.95. That's a third less. Penske shocks take a 2.25" I.D. x 6" long spring. HRP are great people to work with. I have spoke with them many times and they tell me the motorcycle world is just beginning to learn of them. The first point of my "journey" here is to get some good accurate measurements and go from there. Exactly what does my bike weigh front and rear, exactly how much rear end travel do I have, etc. Not relying on numbers from the shop manual or a sales brochure. RDR

I'm looking to learn an empirical/scientific based methodology to determine the correct shock and fork spring(s) for my bike. I am intentionally not going to mention my bike or my weight - just that my riding style can best be described as aggressive twisty riding. I have consulted with all of the suspension "gurus" - Race Tech, Traxxion, Jim Lindemann, Phil Douglas, etc. I have had shock spring rate recommendations anywhere from 950 #/in to 1400 #/in for the same bike and parameters. My shock is a Penske double adjustable by the way. I run that on all my bikes. Surely there has to be some sort of semi-scientific method to determine the optimum spring rate. After all, the springs are the building blocks of a suspension system. Most all of the articles seem to be focused on compression and rebound damping and do little to address whether you have the correct spring to begin with. So far all I have come up with is Andrew Trevitt's "Sportbike Suspension Tuning". I'm not looking for a particular spring rate recommendation (hence why I don't mention which bike or my weight) - I'm looking for a way to determine the parameters for calculating the correct spring rate for both the shock and the fork springs.

Hello Guys, I'm Red Duke Rider. I come from the metro Atlanta area and ride a KTM Duke II, a Honda VFR 800, and a Honda ST1300. Retired from competetive road racing a long time ago. My riding now days is mostly the north GA mountains. I attended a CSS school at Jennings a few years back. You're never to old to learn. I believe Keith Code is one of the greatest teachers/communicators I have ever met. And I don't mean that just in the motorcycle sense - he is simply a great teacher. I would love to see colleges invite Keith in to teach future teachers how to communicate to students and others. He has a unique knack for getting people to think and learn at the same time. I hope to learn from the board as well as contribute. RDR