Rear Set Position

[fossilfuel]

Hi Guy's,

I am getting ready for my first track day of the season and wondered if there is a good indicator or rule of thumb for setting up rear sets for leg position. What is the most important variable that one should consider when setting peg position. I thought about this after having difficulty pressing into my tank with knee for turns. I thought my rear sets might be to high and to for back causing me to push in more of a horizontal plane than vertical. I am 6'2" and use stomp grips. Thanks for any thoughts.

[fossilfuel]

Hi Guy's,

I am getting ready for my first track day of the season and wondered if there is a good indicator or rule of thumb for setting up rear sets for leg position. What is the most important variable that one should consider when setting peg position. I thought about this after having difficulty pressing into my tank with knee for turns. I thought my rear sets might be to high and to for back causing me to push in more of a horizontal plane than vertical. I am 6'2" and use stomp grips. Thanks for any thoughts.

 

 

I did some investigating and came up with the following, could be right could be wrong. I would have to consider that the most important aspect when setting up pegs on after market rear sets is center of gravity. I should position my pegs to create good positioning over the center of gravity of the bike. In my case being 6"2" it might be a little harder to do. According to some articles I have read, a 50%-50% weight distribution is key to the functionality of the motorcycle especially in turns. A forward center of gravity creates over steer with rear wheel slip in turns. With a high center of gravity the rear wheel tends to lift in braking. So in my case, if the pegs are to far back and to high I am rotating my weight to for forward creating oversteer and a high and forward center of gravity when braking. I think if I make the change It should take less effort to stick the knee in to the tank in turns and less arm pressure on the handle bars?

[Cobie Fair]

Personally, my first concern would be how well I could get anchored on the bike, and adjusting the pegs to get the best possible set up on the tank and knees into the tank. I have somewhat a hard time with this, as very short legs, and long torso. There are other adjustments that one can do (like raising or lowering the back or front of the bike) that can effect the weith bias and handling. Most of the Kawi's we have raised the back of the bike, and it's improved the handling.

[adamsys]

Personally, my first concern would be how well I could get anchored on the bike, and adjusting the pegs to get the best possible set up on the tank and knees into the tank.

 

This is a good question for me because I'm planning on making a rear set for myself with my CNC machine. I've been researching how the race bikes are set up. Of course, the MotoGP bikes have only one position which, I assume, is custom tailored to the specific rider's tastes. So what about a novice like me who really doesn't have a specific position preference? Is it purely an ergonomic issue?

 

I know when the pegs are very far rearward, the bike wheelies easier. It took me a while to get my head around that because, as an engineer, my first thought is to think of the rider and bike as a pair of rigid bodies that combine to form a singular rigid body with a center of gravity that is the weighted average of the bike and rider CGs. But that is a flawed notion because the rider is an adaptive mass, sort of like a Segway scooter, that automatically centers its mass over the contact points (pegs mostly). So maybe its better to optimize the peg location and alter that tank ergonomics to suit?

[racer]

In the past, I always went for max height with rearsets. It seemed easier to move my butt off, or back and forth. Not to mention ground clearance. Look at the GP riders and how bent their legs are due to how high the pegs are.

 

I don't think I ever thought about "anchoring" myself the way the school is talking about nowadays. But boy did my thighs get sore from holding myself up the first weekend every year. I bet that anchoring stuff really helps with that!

[fossilfuel]

In the past, I always went for max height with rearsets. It seemed easier to move my butt off, or back and forth. Not to mention ground clearance. Look at the GP riders and how bent their legs are due to how high the pegs are.

 

I don't think I ever thought about "anchoring" myself the way the school is talking about nowadays. But boy did my thighs get sore from holding myself up the first weekend every year. I bet that anchoring stuff really helps with that!

 

 

Racer,

I have always wondered about the geometry of riding and how your set up should be on the pegs or how this effects total body geometry. My wife rides horses and teaches position and where the students feet should be in the stirrups. When I bought a mountain bike the first thing the bike expert did was set up my body position on the bike. When I ride my stationary bike there is a technic for setting up geometry that optimizes muscle efficiency. My problem has been the more laps I put in the harder it is to maintain that leg position and keep my upper body weight off the bars. I will adjust my pegs during a two day in March and see if I can get more contact with my calf and thigh and see if that helps my balance and center of gravity.

My very first Keith Code School the leg anchor was mentioned late in the day by an instructor. I tried it through a down hill turn at about 90 mph dragging my fingers on the concrete curbing with no pressure on my throttle hand. It is a great technic. I just couldn't sustain it and think it is related to my peg postion.

[racer]

Notice the difference in stirrup placement for hunter/jumpers, dressage, western and... thoroughbred racing, eh?

 

I found your points about placement near the CoM intriguing and will give that some more thought. It intuitively makes sense as CoM is sometimes called the 'center of rotation', right?

[fossilfuel]

Notice the difference in stirrup placement for hunter/jumpers, dressage, western and... thoroughbred racing, eh?

 

I found your points about placement near the CoM intriguing and will give that some more thought. It intuitively makes sense as CoM is sometimes called the 'center of rotation', right?

 

Yes, I think you understand the point I am making. If you and I were to buy two new identical sport bikes, you are 5'10" and weigh 165 lbs and I am 6'2" and weigh 200 lbs is the center of mass the same? What can I do to make our CoM the same or as close to it as possible? Maybe nothing?

[racer]

Notice the difference in stirrup placement for hunter/jumpers, dressage, western and... thoroughbred racing, eh?

 

I found your points about placement near the CoM intriguing and will give that some more thought. It intuitively makes sense as CoM is sometimes called the 'center of rotation', right?

 

Yes, I think you understand the point I am making. If you and I were to buy two new identical sport bikes, you are 5'10" and weigh 165 lbs and I am 6'2" and weigh 200 lbs is the center of mass the same? What can I do to make our CoM the same or as close to it as possible? Maybe nothing?

 

I do get your point and it does seem logical. And I think you probably could come pretty close to making one bike/rider combo footpeg position relatively equal to another wrt "static" CoM with some effort. However, I think there might be more going on wrt CoM, body mass distribution, riding position, riding style, musculature and strength, etc than might easily lend itself to a "standardized" footpeg position relative to a dynamic CoM, ie. what works for one rider might not necessarily be good for another even if the footpegs postions are similar wrt CoM.

 

In my experience, footpeg position can be a highly personalized thing for some racers, while others don't seem so concerned with it. At the end of the day, I think the guys who have a very specific preference have tried different positions to find out what works best for them. I have seen mounting plates with several or many different options machined or drilled into them for the purpose of experimenting with footpeg position. Of course, having access to a machine shop helps because, in addition to making a plate like that, everytime you move footpeg position you probably need to create a new shift linkage (unless you arc the various positions around a radius of a single linkage, which would probably be somewhat limiting).

 

That said, there may in fact be some wisdom on the Pro/World Circuits wrt to footpeg position that one could discern by watching the tapes closely (freeze frame, take caliper measurements on the screen, etc ...?)

[fossilfuel]

Notice the difference in stirrup placement for hunter/jumpers, dressage, western and... thoroughbred racing, eh?

 

I found your points about placement near the CoM intriguing and will give that some more thought. It intuitively makes sense as CoM is sometimes called the 'center of rotation', right?

 

Yes, I think you understand the point I am making. If you and I were to buy two new identical sport bikes, you are 5'10" and weigh 165 lbs and I am 6'2" and weigh 200 lbs is the center of mass the same? What can I do to make our CoM the same or as close to it as possible? Maybe nothing?

 

I do get your point and it does seem logical. And I think you probably could come pretty close to making one bike/rider combo footpeg position relatively equal to another wrt "static" CoM with some effort. However, I think there might be more going on wrt CoM, body mass distribution, riding position, riding style, musculature and strength, etc than might easily lend itself to a "standardized" footpeg position relative to a dynamic CoM, ie. what works for one rider might not necessarily be good for another even if the footpegs postions are similar wrt CoM.

 

In my experience, footpeg position can be a highly personalized thing for some racers, while others don't seem so concerned with it. At the end of the day, I think the guys who have a very specific preference have tried different positions to find out what works best for them. I have seen mounting plates with several or many different options machined or drilled into them for the purpose of experimenting with footpeg position. Of course, having access to a machine shop helps because, in addition to making a plate like that, everytime you move footpeg position you probably need to create a new shift linkage (unless you arc the various positions around a radius of a single linkage, which would probably be somewhat limiting).

 

That said, there may in fact be some wisdom on the Pro/World Circuits wrt to footpeg position that one could discern by watching the tapes closely (freeze frame, take caliper measurements on the screen, etc ...?)

 

Thanks Racer. I have really enjoyed the discourse. I will post what I have found after my two day at Barber. Feel free to chime in anytime.

[Cobie Fair]

OK, lets see if we can get some guys to chime in here on a survey, so I'm going to start a survey thread on this.

 

C

[Red Duke Rider]

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.

[Cobie Fair]

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.

 

Hadn't thought of it simply as a relationship, nice! To be crystal clear, 0% would be measuring from the front backwards, correct?

[Red Duke Rider]

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.

 

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.

[Jaybird180]

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.

 

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.

Where is the individuality in that? IOW, what's the use of having adjustable rearsets to suit every rider, why not just a set of non-adjustable?

[Kevin Kane]

Where is the individuality in that? IOW, what's the use of having adjustable rearsets to suit every rider, why not just a set of non-adjustable?

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

[Jaybird180]

Where is the individuality in that? IOW, what's the use of having adjustable rearsets to suit every rider, why not just a set of non-adjustable?

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?).

[Red Duke Rider]

Where is the individuality in that? IOW, what's the use of having adjustable rearsets to suit every rider, why not just a set of non-adjustable?

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.

[Kevin Kane]

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?

 

Jay;

Your tranny won't quit because you swapped out your rearsets; my guess is that your recalcitrant transmission had more to do with your adjustments. If you're having trouble shifting, put your bike on a rear stand and experiment until you have good reach and range of motion. Once you find "your set-up" you can move your attention to another area to improve.

 

I also went through this process with the springs in my forks and rear shock (previous owner was 50+ pounds heavier than me) so it does take some time, energy and $ to dial in your bike...but it is also fun. YRMV.

 

Kevin

[Jaybird180]

If you're having trouble shifting, put your bike on a rear stand and experiment until you have good reach and range of motion.

Why didn't I think of that???

[sleepr]

I'd agree with Kevin on this too. I found when I changed to a heavier boot with less flex and a slightly thicker toe, I had to adjust my shifter angle to get the correct feel and to get complete and good shift, especially 1st to 2nd as this is the longest "throw" in the gearbox. Also my racebike is set up with the shifter a little lower due to shifting while tucked in, while my street bike is a little higher due to the more upright position.

[Cobie Fair]

If you're having trouble shifting, put your bike on a rear stand and experiment until you have good reach and range of motion.

Why didn't I think of that???

 

You know, I have had to adjust the shift lever, and if I do it at a stand still, I usually get it wrong, have to go and ride it for a little and see if I have it right. One thing I notice, my "tendency" is to go a little low, and that makes for missing up shifts now and again (have GP shift).

 

C

[Jaybird180]

If you're having trouble shifting, put your bike on a rear stand and experiment until you have good reach and range of motion.

Why didn't I think of that???

 

You know, I have had to adjust the shift lever, and if I do it at a stand still, I usually get it wrong, have to go and ride it for a little and see if I have it right. One thing I notice, my "tendency" is to go a little low, and that makes for missing up shifts now and again (have GP shift).

 

C

You certainly know how to make a guy feel better about his wrenching skills.

[faylix]

Bought a set of Bohemian Racing rear sets off his website, specified my model on website and on the paypal order (02 GSXR 600)

 

When they came they were packaged very nicely. Parts looked very well made, the bearings were smooth and lubricated. Instructions were basically two pictures of which parts went with which side of the bike and some general tips. Not exactly a step by step guide but informative enough to get the job done.

 

Even included some carbon fiber heal guards. very sexy.

 

Some notes:

 

You have to re-use one of the factory eye bolts for the shifter, the instructions showed a second eye-bolt in the picture but only one was included. Not a big deal, and doing it this way allowed me to re-use the factory rubber cover.

 

I believe some washers (not included, but clearly easy to obtain) will be required to space out the shifter if you want to put it in an aggressive position... which leads me to my next word of caution:

 

When I went to actually mount them to the bike, I ran into some trouble. it looked like the bolts that mount the plate to the frame weren't lining up correctly. Uh oh.

 

After breaking out the trusty calipers I figured out:

 

The distance between the center of each mounting bolt on my frame was about 56 mm. The plates included were 59mm. There was no way I was going to be able to get a screw through both holes!

 

Thankfully someone picked up at BR on a Saturday... but the news wasn't great. I was going to have to wait for them to make another order from China, expected to arrive the next Thursday (today) and then wait for them to ship me the required parts which hadn't exactly been quickly the first time around.

 

*sigh*

 

So they look like a good product for a GREAT price... but seeing as how I already gave my brake side rear set to a buddy that crashed recently I'm walking till I get those plates, I'm missing the first really nice day of the season today and I have a track day coming up Saturday the 18th that I'm worried I'm going to miss.

 

Long story short, measure the bolt pattern on your frame, and when you order make sure they confirm the size on the sets they ship you. Then enjoy your new rearsets that will make everyone who paid 350 or more for vortex or 500 for sato's turn green .

 

Please please please get me my plates soon Dennis.

 

-Faylix.

K2 GSXR 600

-1/+2, DID chain, K&N drop in filter, hot bodies hugger, Bohemian Racing rear sets.

super awesome custom rashed up plastics from the guy that bought the bike, low sided once and never rode it again before selling it to me for a great price %).

 

PS:

I'm from Boston

I joined this forum to make this post

I do think BR makes a good product here

I am for sure not trying to flame BR, but

I wish someone had told me to be careful and confirm the measurements before I spent $210, gave away a piece of my baby, and now can't ride.

[Cobie Fair]

Hey Faylix,

 

Want to let us know how it finally sorts out?

 

CF