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Lateral grip is not needed when the bike is upright. That is why it does not matter if the front end uses 100% of the suspension travel and bottoms out, when you start braking.A few lines of wisdom on suspensions. You never want to use 100 percent of the travel on a front fork. Most of the time 80-85 percent of travel is fine with an unexpected bump at race pace taking to close to 100 percent of travel. If you are constantly at 100 percent of travel when you hit that bump at race pace the suspension has no travel left to react.
And as you can see from the data, that is normal behaviour for track only bikes front end. And you can also see from the data, that everywhere else suspension is not close to bottom out. So when lateral grip is needed, suspension has travel left to react to unexpected bumps.
Take any fast bike/rider; their front end will bottom out a few times per lap/ as you can see from the data.
If they would try to prevent that, they would either have to brake much less, and lose at least a couple of seconds per lap.
Or they would have to stiffen up front end so much, that they would loose too much front end traction, and again they would loose at least a couple of seconds per lap.
That is why Dave Moss 80/20% rules are not a problem for slow riders, or street riders, or for people who do not understand suspension basics.
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"Take any fast bike rider, their front end will bottom out a few times per lap"....Lateral grip is not needed when the bike is upright. That is why it does not matter if the front end uses 100% of the suspension travel and bottoms out, when you start braking.
And as you can see from the data, that is normal behaviour for track only bikes front end. And you can also see from the data, that everywhere else suspension is not close to bottom out. So when lateral grip is needed, suspension has travel left to react to unexpected bumps.
Take any fast bike/rider; their front end will bottom out a few times per lap/ as you can see from the data.
If they would try to prevent that, they would either have to brake much less, and lose at least a couple of seconds per lap.
Or they would have to stiffen up front end so much, that they would loose too much front end traction, and again they would loose at least a couple of seconds per lap.
That is why Dave Moss 80/20% rules are not a problem for slow riders, or street riders, or for people who do not understand suspension basics.
Like I said, take the fastest riders from WSBK and MotoGP and try to tell me they're bottoming their forks. You can make huge generalisations but keep in mind that this encompasses all the "fast" riders that still have an incorrect spring or damping in their forks.
"As you can see from the data"....
Well I can't see anything from the 'data'. All you've provided us is some graph with no indication of what is being measured against what, and then you've added your own red line which is meant to mean something, for some fast rider.
You are still yet to provide any credible information to support your idea.
Lets see if you can explain to the folks here how exactly a bike under hard braking that uses 90-95% of it's fork travel will have less grip than a bike that has used 100% of it's travel and has bottomed out?
I have added a graph that provides a clearer picture for our viewers...
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As everybody has already noticed, only our own suspension God can give you credible info that your ego approves. He is the only credible source for you, everything else is just blasbhemy in our eyes."Take any fast bike rider, their front end will bottom out a few times per lap"....
Like I said, take the fastest riders from WSBK and MotoGP and try to tell me they're bottoming their forks. You can make huge generalisations but keep in mind that this encompasses all the "fast" riders that still have an incorrect spring or damping in their forks.
"As you can see from the data"....
Well I can't see anything from the 'data'. All you've provided us is some graph with no indication of what is being measured against what, and then you've added your own red line which is meant to mean something, for some fast rider.
You are still yet to provide any credible information to support your idea.
Lets see if you can explain to the folks here how exactly a bike under hard braking that uses 90-95% of it's fork travel will have less grip than a bike that has used 100% of it's travel and has bottomed out?
I have added a graph that provides a clearer picture for our viewers...
So next time you meet Him, ask Him is the fastest riders from WSBK and MotoGP are bottoming their forks, and how often that occurs per one lap. Do not be suprised if the answer is something totally unexpected/ against your current "truths".
Because you do not understand suspension basics, I also assumed that you do not have any experiense on suspension data logging and analysing. That is why I tried to make the data as simple as possible for you to understand. But no luck...
For other thread readers:
If you have any kind of questions about track only bike front end bottoming out and/or suspension data regarding that, just ask. I'm happy to share the knowledge what I have gained in past ~11 years.
And as I said previously, Dave Moss has some good info and some bad info. Most of hes clients are riding street bikes with stock suspension on road or on track, and that is totally different situation than track only bike. That is why you should always put the info to correct context, and if you do not now suspension basics, it is hard for you to know what would be the correct context.
A Suggestion
I suggest a suspension book that might be informative ;
Race Tech's Motorcycle Suspension Bible
by Paul Thede & Lee Parks
Published by Motorbooks Workshop
I suggest a suspension book that might be informative ;
Race Tech's Motorcycle Suspension Bible
by Paul Thede & Lee Parks
Published by Motorbooks Workshop
this is relevant to me because i am transitioning my street bike to track only - what changes do you think i should make to suspension?As everybody has already noticed, only our own suspension God can give you credible info that your ego approves. He is the only credible source for you, everything else is just blasbhemy in our eyes.
So next time you meet Him, ask Him is the fastest riders from WSBK and MotoGP are bottoming their forks, and how often that occurs per one lap. Do not be suprised if the answer is something totally unexpected/ against your current "truths".
Because you do not understand suspension basics, I also assumed that you do not have any experiense on suspension data logging and analysing. That is why I tried to make the data as simple as possible for you to understand. But no luck...
For other thread readers:
If you have any kind of questions about track only bike front end bottoming out and/or suspension data regarding that, just ask. I'm happy to share the knowledge what I have gained in past ~11 years.
And as I said previously, Dave Moss has some good info and some bad info. Most of hes clients are riding street bikes with stock suspension on road or on track, and that is totally different situation than track only bike. That is why you should always put the info to correct context, and if you do not now suspension basics, it is hard for you to know what would be the correct context.
2015 DDC
i already did a whole season on slicks and tire wear and pressures are good so the suspension isn't too far off unless i'm riding around it unconsciously
nice i found a .pdf of thatI suggest a suspension book that might be informative ;
Race Tech's Motorcycle Suspension Bible
by Paul Thede & Lee Parks
Published by Motorbooks Workshop
[pdfview]http://v4musclebike.com/articles/RACETECH-SUSPENSION-BIBLE.pdf[/pdfview]
It depens on where you are now and what is your target. That will tell what kind of tools you need to achieve what you are looking for.this is relevant to me because i am transitioning my street bike to track only - what changes do you think i should make to suspension?
2015 DDC
i already did a whole season on slicks and tire wear and pressures are good so the suspension isn't too far off unless i'm riding around it unconsciously
Do you want to keep the DDC and test and learn to tune it, or are you going for conventional internals? Do you have the front suspension sensor and datalogger?
What is your budget for front end?
What is your riding skill level? What is your pace? What is your braking ability?
Is the bikes weight stock or is it stripped for track use? What is your weight?
= How much you need load carrying capacity for front end (bike+you+braking))/ what kind of stress the front end have to cope with?
https://youtu.be/UEqzjKrWhAkAs everybody has already noticed, only our own suspension God can give you credible info that your ego approves. He is the only credible source for you, everything else is just blasbhemy in our eyes."Take any fast bike rider, their front end will bottom out a few times per lap"....
Like I said, take the fastest riders from WSBK and MotoGP and try to tell me they're bottoming their forks. You can make huge generalisations but keep in mind that this encompasses all the "fast" riders that still have an incorrect spring or damping in their forks.
"As you can see from the data"....
Well I can't see anything from the 'data'. All you've provided us is some graph with no indication of what is being measured against what, and then you've added your own red line which is meant to mean something, for some fast rider.
You are still yet to provide any credible information to support your idea.
Lets see if you can explain to the folks here how exactly a bike under hard braking that uses 90-95% of it's fork travel will have less grip than a bike that has used 100% of it's travel and has bottomed out?
I have added a graph that provides a clearer picture for our viewers...
So next time you meet Him, ask Him is the fastest riders from WSBK and MotoGP are bottoming their forks, and how often that occurs per one lap. Do not be suprised if the answer is something totally unexpected/ against your current "truths".
Because you do not understand suspension basics, I also assumed that you do not have any experiense on suspension data logging and analysing. That is why I tried to make the data as simple as possible for you to understand. But no luck...
For other thread readers:
If you have any kind of questions about track only bike front end bottoming out and/or suspension data regarding that, just ask. I'm happy to share the knowledge what I have gained in past ~11 years.
And as I said previously, Dave Moss has some good info and some bad info. Most of hes clients are riding street bikes with stock suspension on road or on track, and that is totally different situation than track only bike. That is why you should always put the info to correct context, and if you do not now suspension basics, it is hard for you to know what would be the correct context.
Motegi Circuit... I think these guys are some fairly accomplished riders and it doesn't look like they're bottoming.
I am keeping the ddc with no budget for sensor or logger.It depens on where you are now and what is your target. That will tell what kind of tools you need to achieve what you are looking for.
Do you want to keep the DDC and test and learn to tune it, or are you going for conventional internals? Do you have the front suspension sensor and datalogger?
What is your budget for front end?
What is your riding skill level? What is your pace? What is your braking ability?
Is the bikes weight stock or is it stripped for track use? What is your weight?
= How much you need load carrying capacity for front end (bike+you+braking))/ what kind of stress the front end have to cope with?
My forks get new oil before next season but that’s it as far as mods
This is my first year on track with 13 days, last three in A group, mid pack. The bike is getting track plastics so it will be losing some weight. I am around 220lbs geared up
Zero-budget? Well, in that case it is quite simple: You just need to always keep in mind that when the front end bottoms out at the start of the braking; there is your front ends limit, it can not cope with any stronger stress than that. So, front end might feel a bit weak, but that is the result of the zero-buget.I am keeping the ddc with no budget for sensor or logger.
My forks get new oil before next season but that’s it as far as mods
This is my first year on track with 13 days, last three in A group, mid pack. The bike is getting track plastics so it will be losing some weight. I am around 220lbs geared up
It does not matter if you hit the brakes hard, or if you slowly increase the squeez; your front end will bottom out, because in either case it has to carry the load you are pushing on top of it.
And it does not matter if you feel that the deceleration is only 70-80% when the front end starts to squirm a little bit. There is the limit.
If you want to get in to the trouble, just think once "I am braking so softly..." ,"How about..." or "Just a little bit..." while riding on the track, and you will try to do something what your bike is not capable to. You have to first change te bikes capability before you can "Just a little bit more..."
So, know the (zero-buget) limit, and drive according to it. It is very easy to forget it.
This thread has now gone officially "FULL RETARD". You never want to go full retard. Only good thing is this is almost as entertaining as reading a zoo post, but people are going to read this **** and actually believe it and are going to get hurt.Zero-budget? Well, in that case it is quite simple: You just need to always keep in mind that when the front end bottoms out at the start of the braking; there is your front ends limit, it can not cope with any stronger stress than that. So, front end might feel a bit weak, but that is the result of the zero-buget.
It does not matter if you hit the brakes hard, or if you slowly increase the squeez; your front end will bottom out, because in either case it has to carry the load you are pushing on top of it.
And it does not matter if you feel that the deceleration is only 70-80% when the front end starts to squirm a little bit. There is the limit.
If you want to get in to the trouble, just think once "I am braking so softly..." ,"How about..." or "Just a little bit..." while riding on the track, and you will try to do something what your bike is not capable to. You have to first change te bikes capability before you can "Just a little bit more..."
So, know the (zero-buget) limit, and drive according to it. It is very easy to forget it.
Perhaps a Harley hardtail is the pinnacle of handling prowess.
No advice on settings? Just that when the front dives, it dives?Zero-budget? Well, in that case it is quite simple: You just need to always keep in mind that when the front end bottoms out at the start of the braking; there is your front ends limit, it can not cope with any stronger stress than that. So, front end might feel a bit weak, but that is the result of the zero-buget.
It does not matter if you hit the brakes hard, or if you slowly increase the squeez; your front end will bottom out, because in either case it has to carry the load you are pushing on top of it.
And it does not matter if you feel that the deceleration is only 70-80% when the front end starts to squirm a little bit. There is the limit.
If you want to get in to the trouble, just think once "I am braking so softly..." ,"How about..." or "Just a little bit..." while riding on the track, and you will try to do something what your bike is not capable to. You have to first change te bikes capability before you can "Just a little bit more..."
So, know the (zero-buget) limit, and drive according to it. It is very easy to forget it.
DDC has 9.5 and 11.5 front springs, not soft at all
DDC has complaints of no feeling mid corner, because DDC opens valving to better follow the road surface when leaned over. This is to ensure the same force required to move chassis up 1" at 45 degrees of lean is the same as when chassis is vertical.
I'm curious to know why I need a budget for the front end, care to enlighten? I only have one season of track experience and always like to hear from those with more :grin2: especially from someone with 11 years and is only +5 off of course records
I tried... But that is exactly the point. I don't want to see anyone misinformed.This thread has now gone officially "FULL RETARD". You never want to go full retard. Only good thing is this is almost as entertaining as reading a zoo post, but people are going to read this **** and actually believe it and are going to get hurt.Zero-budget? Well, in that case it is quite simple: You just need to always keep in mind that when the front end bottoms out at the start of the braking; there is your front ends limit, it can not cope with any stronger stress than that. So, front end might feel a bit weak, but that is the result of the zero-buget.
It does not matter if you hit the brakes hard, or if you slowly increase the squeez; your front end will bottom out, because in either case it has to carry the load you are pushing on top of it.
And it does not matter if you feel that the deceleration is only 70-80% when the front end starts to squirm a little bit. There is the limit.
If you want to get in to the trouble, just think once "I am braking so softly..." ,"How about..." or "Just a little bit..." while riding on the track, and you will try to do something what your bike is not capable to. You have to first change te bikes capability before you can "Just a little bit more..."
So, know the (zero-buget) limit, and drive according to it. It is very easy to forget it.
I do not know your current settings, I do not know how your bike behaves, I do not know what kind of changes you would like to make to your bikes behaviour. Based on that, how could I give any advice on settings? I or anybody else could give you some random lottery generic settings, but they are as useful to you as a zip tie in your bikes front fork or in your wrist.No advice on settings? Just that when the front dives, it dives?
DDC has 9.5 and 11.5 front springs, not soft at all
DDC has complaints of no feeling mid corner, because DDC opens valving to better follow the road surface when leaned over. This is to ensure the same force required to move chassis up 1" at 45 degrees of lean is the same as when chassis is vertical.
I'm curious to know why I need a budget for the front end, care to enlighten? I only have one season of track experience and always like to hear from those with more :grin2: especially from someone with 11 years and is only +5 off of course records
And related to that: That is why I like data loggers. Because the driver might be lying unwittingly to himself. Data does not lie, and it will tell you everything about the front end if you have the sensor. And the 2D data logger is plug and play, fits any YM (easy to sell), easy to use, it will tell you Everything about the bike, and it is cheap as hell when compaired to its features.
9.5&11.5 is kind of soft for 220 lbs rider. For comparison: I'm about the same weight, 11.5 springs, 40 mm sag, additonal 5 mm front end total travel (K-TechDDS cartridges), and front end (still) bottoms out with maximum braking.
If you want to convert a stock street bike to a track only bike, you need a budget. If you have zero-budget, then you have a mass production stock street bike with mass production stock street bike suspension which is aimed for free spirited office workers riding on streets, and that sets some limits.
But, back to generic settings, step one: Do you know what is a top out spring(s)? And how it works etc?
If you do not, then for example:
Graph:
https://www.sportrider.com/tech/ask-geek-fork-top-out-springs#page-2
Some info:
https://www.sportrider.com/how-do-top-out-springs-affect-sag
Apply full preload setting to front forks.
Lift your bikes front end up to the air. Put a zip tie in to the bikes front fork (Did I just say that!?), lift the zip tie up to the cup, and then press down the font wheel and see if the front fork extends just a bit and retracts.
If it extends then you can use full preload setting without losing the sensitivity of the front end when front end is fully extended. In most cases the top out spring is designed so that it should work up to full preload. But you have to test it to make sure.
If it does not extend, loosen up preload one turn at a time and see when you are able extend the front fork when pressing down the front wheel. Then you know when you start to lose some of the front fork sensitivity when fully extended vs preload setting. It is not a big thing, but nice to know.
Also, press down the front wheel and keep it there, lift the zip tie up to the cup, and measure total length between zip tie and fork bottom. That is the free length of the front fork to be used when measuring sag. It is easyest to measure with vernier caliper.
Bump stops is set higher in the fork :grin2::grin2::grin2::grin2:https://youtu.be/UEqzjKrWhAk
Motegi Circuit... I think these guys are some fairly accomplished riders and it doesn't look like they're bottoming.
I have been racing for a very long time and the last thing I want my bike to do is bottom out...
Do you have datalogger and suspension data?I have been racing for a very long time and the last thing I want my bike to do is bottom out...
What you have done/ what do you do to avoid bottoming out?
Generic track only settings, step two:
(Still full preload setting in the fork(s).)
Note that empty tank vs full tank (21 litres/ 15,75 kg) will affect about 3 mm to sag. And full leather riding gear (~10 kg) about 2 mm. So, if you have half a tank gas and no gear on you, add 3-4 mm to the measured sag value. With stock geometry (23.5 deg) and springs (9.5&10.5), 2015 S1000RR has about 2,546 kg/mm vertical spring rate on front axle.
For sag measuring you need someone to measure, and you can use pit stand to keep the rear stable. Put some extension rods to rear axle hole to get the pit stand fulcrum to correct place/ do not use bobbins in the swing arm. If you do not have suitable pit stand, you need someone to keep the bike steady.
Put the bike on a even ground. Jump on the saddle, tuck down and stay there. Do not use front brake.
(Somebody) Push down the front end and let it smoothly up. Lift the zip tie up to the cup and measure visible part of the tube.
Lift the front end up and let it smoothly down. Zip up and measure.
Calculate average visible fork tube length and substract it from the free length.
Now you have rider sag value.
Rider sag (with full tank) should be about max 40 mm, and if you have 120 mm total travel, then compression travel is 80 mm and extension travel is about 40 mm (same as rider sag). That is a classic 1/3 vs 2/3 partition.
If the sag is more than 40 mm then you obviously need stiffer springs, or with zero buget just deal with it, and do not try to brake any harder when the front end starts to squirm (bottom out). You can also stiffen up the air spring by adding oil, if want to try to battle against bottoming, but then you loose some of the front end linearity. If you add compression damping, front end will still bottom out with the same braking force, but only a little bit later (0,1-0,3 seconds or something like that). Suspension will travel as much as before when braking, but everywhere else it will travel a bit less and puts more stress on the tyre and there will also be a bit less traction.
If the rider sag is less than 35 mm, most probably not with 220 lbs geared rider, then you can use preload adjuster and adjust the rider sag.
Or if you would like to have less rider sag than 35 mm, it is your choice, but then you loose as much extension travel. Versus it is nice to have extesion travel when you are in maximum lean angle in apex and hit some groove or rut. You will rather bottom out when you are upright when braking, than top out when you are at maximum lean angle.
So know what you are doing, what you win vs what you loose, and you can make a compromise which suits for you. And then you also know what kind of limits the suspension has on different parts of the track.
(Still full preload setting in the fork(s).)
Note that empty tank vs full tank (21 litres/ 15,75 kg) will affect about 3 mm to sag. And full leather riding gear (~10 kg) about 2 mm. So, if you have half a tank gas and no gear on you, add 3-4 mm to the measured sag value. With stock geometry (23.5 deg) and springs (9.5&10.5), 2015 S1000RR has about 2,546 kg/mm vertical spring rate on front axle.
For sag measuring you need someone to measure, and you can use pit stand to keep the rear stable. Put some extension rods to rear axle hole to get the pit stand fulcrum to correct place/ do not use bobbins in the swing arm. If you do not have suitable pit stand, you need someone to keep the bike steady.
Put the bike on a even ground. Jump on the saddle, tuck down and stay there. Do not use front brake.
(Somebody) Push down the front end and let it smoothly up. Lift the zip tie up to the cup and measure visible part of the tube.
Lift the front end up and let it smoothly down. Zip up and measure.
Calculate average visible fork tube length and substract it from the free length.
Now you have rider sag value.
Rider sag (with full tank) should be about max 40 mm, and if you have 120 mm total travel, then compression travel is 80 mm and extension travel is about 40 mm (same as rider sag). That is a classic 1/3 vs 2/3 partition.
If the sag is more than 40 mm then you obviously need stiffer springs, or with zero buget just deal with it, and do not try to brake any harder when the front end starts to squirm (bottom out). You can also stiffen up the air spring by adding oil, if want to try to battle against bottoming, but then you loose some of the front end linearity. If you add compression damping, front end will still bottom out with the same braking force, but only a little bit later (0,1-0,3 seconds or something like that). Suspension will travel as much as before when braking, but everywhere else it will travel a bit less and puts more stress on the tyre and there will also be a bit less traction.
If the rider sag is less than 35 mm, most probably not with 220 lbs geared rider, then you can use preload adjuster and adjust the rider sag.
Or if you would like to have less rider sag than 35 mm, it is your choice, but then you loose as much extension travel. Versus it is nice to have extesion travel when you are in maximum lean angle in apex and hit some groove or rut. You will rather bottom out when you are upright when braking, than top out when you are at maximum lean angle.
So know what you are doing, what you win vs what you loose, and you can make a compromise which suits for you. And then you also know what kind of limits the suspension has on different parts of the track.
Seriously sounds like Shervin
http://blog.motorcycle.com/2010/05/...n-exhaust-and-cutting-holes-in-the-frame/amp/
http://blog.motorcycle.com/2010/05/...n-exhaust-and-cutting-holes-in-the-frame/amp/
In July I might be ready to drop in suspension, thinking Öhlins nix 30 and ttx GPGeneric track only settings, step two:
(Still full preload setting in the fork(s).)
Note that empty tank vs full tank (21 litres/ 15,75 kg) will affect about 3 mm to sag. And full leather riding gear (~10 kg) about 2 mm. So, if you have half a tank gas and no gear on you, add 3-4 mm to the measured sag value. With stock geometry (23.5 deg) and springs (9.5&10.5), 2015 S1000RR has about 2,546 kg/mm vertical spring rate on front axle.
For sag measuring you need someone to measure, and you can use pit stand to keep the rear stable. Put some extension rods to rear axle hole to get the pit stand fulcrum to correct place/ do not use bobbins in the swing arm. If you do not have suitable pit stand, you need someone to keep the bike steady.
Put the bike on a even ground. Jump on the saddle, tuck down and stay there. Do not use front brake.
(Somebody) Push down the front end and let it smoothly up. Lift the zip tie up to the cup and measure visible part of the tube.
Lift the front end up and let it smoothly down. Zip up and measure.
Calculate average visible fork tube length and substract it from the free length.
Now you have rider sag value.
Rider sag (with full tank) should be about max 40 mm, and if you have 120 mm total travel, then compression travel is 80 mm and extension travel is about 40 mm (same as rider sag). That is a classic 1/3 vs 2/3 partition.
If the sag is more than 40 mm then you obviously need stiffer springs, or with zero buget just deal with it, and do not try to brake any harder when the front end starts to squirm (bottom out). You can also stiffen up the air spring by adding oil, if want to try to battle against bottoming, but then you loose some of the front end linearity. If you add compression damping, front end will still bottom out with the same braking force, but only a little bit later (0,1-0,3 seconds or something like that). Suspension will travel as much as before when braking, but everywhere else it will travel a bit less and puts more stress on the tyre and there will also be a bit less traction.
If the rider sag is less than 35 mm, most probably not with 220 lbs geared rider, then you can use preload adjuster and adjust the rider sag.
Or if you would like to have less rider sag than 35 mm, it is your choice, but then you loose as much extension travel. Versus it is nice to have extesion travel when you are in maximum lean angle in apex and hit some groove or rut. You will rather bottom out when you are upright when braking, than top out when you are at maximum lean angle.
So know what you are doing, what you win vs what you loose, and you can make a compromise which suits for you. And then you also know what kind of limits the suspension has on different parts of the track.
What made you choose ktech?
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