Jump to content

Questions About Braking Mods And A Braking Problem


Recommended Posts

Hi guys!! Need some advice from you expert track riders/racers out there!!

1, How much braking improvement can you get out of a master cylinder upgrade(i.e Brambo radial m/c etc)?? what about fancy rotors like Galfer wave floating rotors?? which one would benefit more(regardless or price)??

I've heard brake pads and brake lines make the most difference in providing braking power and consistency.. what would be the second most effective mods??

2, I've just started riding advanced group on trackdays for about half a season.. I don't have strong forearms to deal with long, constant hard braking.. my right wrist and arm get fatigued easily(in 3-4laps) due to hard pressure and vibration caused under braking.. what's the best way to reduce the vibration caused by braking or to fix the problem??

Thanks

Link to comment
Share on other sites

Vibration under braking will only, in my experience, happen because of three different things; varped discs, uneven discs (not uniform thickness or overheated in spots) or suspension that's bottomed out. To check for the latter, fit tie wraps around the fork legs and brake as you do and see whether you have used up all travel on the forks.

Link to comment
Share on other sites

Vibration under braking will only, in my experience, happen because of three different things; varped discs, uneven discs (not uniform thickness or overheated in spots) or suspension that's bottomed out. To check for the latter, fit tie wraps around the fork legs and brake as you do and see whether you have used up all travel on the forks.

 

yes.. in fact, I already have the zip-tie in place and in all the trackdays I've done, I have never bottomed out my front fork riding track.. (maybe one time goofing around doing wheelie on streets, but that's it)

Link to comment
Share on other sites

I agree with Eirik, severe vibrations under braking should only happen if something is wrong.

If you have a front lifter, get the front wheel off the ground and rotate the wheel to see if the disc is warped. You can also use a black marker to test for warpage - simply place the filt pen a couple of hundreds from the outside of the disc and rotate the wheel. Any change in gap (or even ink on the braking disc) will reveal a warped disc. Oh, and do check both discs.

 

Anyways, getting fatigue in your hand and forearm from braking is plain wrong.

 

Kai

Link to comment
Share on other sites

I agree with Eirik, severe vibrations under braking should only happen if something is wrong.

If you have a front lifter, get the front wheel off the ground and rotate the wheel to see if the disc is warped. You can also use a black marker to test for warpage - simply place the filt pen a couple of hundreds from the outside of the disc and rotate the wheel. Any change in gap (or even ink on the braking disc) will reveal a warped disc. Oh, and do check both discs.

 

Anyways, getting fatigue in your hand and forearm from braking is plain wrong.

 

Kai

 

great advice!! I'll be sure to check those discs.. both!!

 

what you said about fatiguing in hand and forearm actually got me really curious.. how are they supposed to feel like when you are braking hard?? I'm firmly applying my brake while trying to maintain my forearms as level as possible at the same time keeping myself as close to the back of the seat as possible.. which would be something like grappling on to the brake lever while pushing my body away from the front of the bike with my arms.. the force is quite intense, and that took a lot of strength and energy to do. How is it possible to hard brake without gripping on strongly??

Link to comment
Share on other sites

I agree with Eirik, severe vibrations under braking should only happen if something is wrong.

If you have a front lifter, get the front wheel off the ground and rotate the wheel to see if the disc is warped. You can also use a black marker to test for warpage - simply place the filt pen a couple of hundreds from the outside of the disc and rotate the wheel. Any change in gap (or even ink on the braking disc) will reveal a warped disc. Oh, and do check both discs.

 

Anyways, getting fatigue in your hand and forearm from braking is plain wrong.

 

Kai

 

great advice!! I'll be sure to check those discs.. both!!

 

what you said about fatiguing in hand and forearm actually got me really curious.. how are they supposed to feel like when you are braking hard?? I'm firmly applying my brake while trying to maintain my forearms as level as possible at the same time keeping myself as close to the back of the seat as possible.. which would be something like grappling on to the brake lever while pushing my body away from the front of the bike with my arms.. the force is quite intense, and that took a lot of strength and energy to do. How is it possible to hard brake without gripping on strongly??

 

 

Gday mate,

 

Just wondering if you have attended a school level yet? I think the problem is your holding on too tight to the bars and getting 'wrist pump', the more you straighten your arms ie lock them out and increase your grip whilst pushing yourself away on the hangers (like white knuckle tight), the more the forces will transfer throughout the bike causing a bit more instability, basically your stopping the bike from doing its thing. We also need to look at what your doing with your knees, are you locked onto your tank and using the pressure from the inside of your knees to provide stability? Doing this gives you the ability to loosen/relax your arms, so they kinda work like shock absorbers allowing the bike to correct itself. Doing this should get rid of your arm pump and sore wrists.

 

I would suggest to buy the Twist DVD because Keith actually covers this exact point in depth and explained alot better than I can. Hope my 2 cents worth helpssmile.gif

 

Dylan

Link to comment
Share on other sites

what you said about fatiguing in hand and forearm actually got me really curious.. how are they supposed to feel like when you are braking hard?? I'm firmly applying my brake while trying to maintain my forearms as level as possible at the same time keeping myself as close to the back of the seat as possible.. which would be something like grappling on to the brake lever while pushing my body away from the front of the bike with my arms.. the force is quite intense, and that took a lot of strength and energy to do. How is it possible to hard brake without gripping on strongly??

 

So that is really generating the fatigue here? pushing the braking lever? holding on to the handlebars? - or holding your body weight back while braking?

 

As Dylan is writing, you need to be using your legs to push into the tank to stabilize your body and take the weight away from the handlebars. Simultaneously, your need to use your abdominal and back muscles to reduce the amount of weight thrown onto the handlebars.

 

Oh, and this will have the positive side effect of having less unplanned steering input; pushing on the handlebars to keep your weight back will generate an unplanned and undesired steering input, which could affect the bike's stability and trajectory. As a motorcycle safety course instructor, I regularly see riders give uneven input to the handlebars while braking, causing the bike to get slightly out of vertical and thereby increasing the risk of crashing, should the front wheel lock up.

 

Regards,

 

Kai

Link to comment
Share on other sites

I agree with Eirik, severe vibrations under braking should only happen if something is wrong.

If you have a front lifter, get the front wheel off the ground and rotate the wheel to see if the disc is warped. You can also use a black marker to test for warpage - simply place the filt pen a couple of hundreds from the outside of the disc and rotate the wheel. Any change in gap (or even ink on the braking disc) will reveal a warped disc. Oh, and do check both discs.

 

Anyways, getting fatigue in your hand and forearm from braking is plain wrong.

 

Kai

 

great advice!! I'll be sure to check those discs.. both!!

 

what you said about fatiguing in hand and forearm actually got me really curious.. how are they supposed to feel like when you are braking hard?? I'm firmly applying my brake while trying to maintain my forearms as level as possible at the same time keeping myself as close to the back of the seat as possible.. which would be something like grappling on to the brake lever while pushing my body away from the front of the bike with my arms.. the force is quite intense, and that took a lot of strength and energy to do. How is it possible to hard brake without gripping on strongly??

 

 

Gday mate,

 

Just wondering if you have attended a school level yet? I think the problem is your holding on too tight to the bars and getting 'wrist pump', the more you straighten your arms ie lock them out and increase your grip whilst pushing yourself away on the hangers (like white knuckle tight), the more the forces will transfer throughout the bike causing a bit more instability, basically your stopping the bike from doing its thing. We also need to look at what your doing with your knees, are you locked onto your tank and using the pressure from the inside of your knees to provide stability? Doing this gives you the ability to loosen/relax your arms, so they kinda work like shock absorbers allowing the bike to correct itself. Doing this should get rid of your arm pump and sore wrists.

 

I would suggest to buy the Twist DVD because Keith actually covers this exact point in depth and explained alot better than I can. Hope my 2 cents worth helpssmile.gif

 

Dylan

 

Thanks for the pointer dylan~ that is very similar to what Stuman says on the other thread.. btw.. i just looked into the dvd and order myself one thanks

Link to comment
Share on other sites

what you said about fatiguing in hand and forearm actually got me really curious.. how are they supposed to feel like when you are braking hard?? I'm firmly applying my brake while trying to maintain my forearms as level as possible at the same time keeping myself as close to the back of the seat as possible.. which would be something like grappling on to the brake lever while pushing my body away from the front of the bike with my arms.. the force is quite intense, and that took a lot of strength and energy to do. How is it possible to hard brake without gripping on strongly??

 

So that is really generating the fatigue here? pushing the braking lever? holding on to the handlebars? - or holding your body weight back while braking?

 

As Dylan is writing, you need to be using your legs to push into the tank to stabilize your body and take the weight away from the handlebars. Simultaneously, your need to use your abdominal and back muscles to reduce the amount of weight thrown onto the handlebars.

 

Oh, and this will have the positive side effect of having less unplanned steering input; pushing on the handlebars to keep your weight back will generate an unplanned and undesired steering input, which could affect the bike's stability and trajectory. As a motorcycle safety course instructor, I regularly see riders give uneven input to the handlebars while braking, causing the bike to get slightly out of vertical and thereby increasing the risk of crashing, should the front wheel lock up.

 

Regards,

 

Kai

 

good advice.. thank you Kai.. I understand the tank gripping concept but couldn't execute it right... as soon I stick my knee out.. then I rely on my arms.. but I think i'm starting to get the idea

Link to comment
Share on other sites

good advice.. thank you Kai.. I understand the tank gripping concept but couldn't execute it right... as soon I stick my knee out.. then I rely on my arms.. but I think i'm starting to get the idea

I am not able to grip the tank well with just one knee (probably an issue of technique here), so what I do is I drive the inside knee into the tank when I'm braking, before flipping it out at the Turn Point. Since the heavy braking is done while the bike is mostly upright, the inside knee won't be anywhere close to the pavement to make use as a lean angle gauge, and conversely, when I get the to the Turn Point most of the braking is done, so I don't need the extra support from the inner knee to stop me from throwing my weight forward.

 

It's a classic case of "works for me", but try it out and see if you can make it work for yourself.

Anyway, let us all know how it worked out for you.

 

Best regards, Kai

Link to comment
Share on other sites

Prolly not relevant here, but since when did I ever put of relevant information anyway laugh.gif It seems that more and more (world level) racers use their inside leg as an airbrake. They used to stick the knee out, but now they have the whole leg off the peg, dangling to make it as large as possible. Now, is this to stop quicker (and suffer added stress on arms/hands/shoulders in the process) or a balance thing (which Rossi claimed when he introduced the technique)?

Link to comment
Share on other sites

good advice.. thank you Kai.. I understand the tank gripping concept but couldn't execute it right... as soon I stick my knee out.. then I rely on my arms.. but I think i'm starting to get the idea

I am not able to grip the tank well with just one knee (probably an issue of technique here), so what I do is I drive the inside knee into the tank when I'm braking, before flipping it out at the Turn Point. Since the heavy braking is done while the bike is mostly upright, the inside knee won't be anywhere close to the pavement to make use as a lean angle gauge, and conversely, when I get the to the Turn Point most of the braking is done, so I don't need the extra support from the inner knee to stop me from throwing my weight forward.

 

It's a classic case of "works for me", but try it out and see if you can make it work for yourself.

Anyway, let us all know how it worked out for you.

 

Best regards, Kai

 

will do!! thanks!! :) my next track day won't happen until late-september though... gosh I can't wait

Link to comment
Share on other sites

Prolly not relevant here, but since when did I ever put of relevant information anyway laugh.gif It seems that more and more (world level) racers use their inside leg as an airbrake. They used to stick the knee out, but now they have the whole leg off the peg, dangling to make it as large as possible. Now, is this to stop quicker (and suffer added stress on arms/hands/shoulders in the process) or a balance thing (which Rossi claimed when he introduced the technique)?

 

that actually is the same question that's been troubling my mind for years!!! :huh:

Link to comment
Share on other sites

I was thinking more about this thread something also to consider is the your brake lines are they braided lines or OEM? Braided lines in my opinion should be fitted, if your upgrading your brake package, as this does help to stop brake fade. If Im getting this wrong someone please pick me up.

 

With the OEM lines when they get hot they expand which in turn causes the brake lines and fluid to loose pressure making the brakes feel like you need to squeeze even harder to get the stopping power you want (which BTW doesnt happen), could be another reason why your getting arm pump maybe not.

 

Plenty more technical people in here that can explain this to us better than I can.

 

Dylan

Link to comment
Share on other sites

I was thinking more about this thread something also to consider is the your brake lines are they braided lines or OEM? Braided lines in my opinion should be fitted, if your upgrading your brake package, as this does help to stop brake fade. If Im getting this wrong someone please pick me up.

 

With the OEM lines when they get hot they expand which in turn causes the brake lines and fluid to loose pressure making the brakes feel like you need to squeeze even harder to get the stopping power you want (which BTW doesnt happen), could be another reason why your getting arm pump maybe not.

 

Plenty more technical people in here that can explain this to us better than I can.

 

Dylan

All brake lines (OEM or aftermarket, braided or not) should be replaced at least every four years, due to the UV radiation causing the plastics to deteriorate. The brake fluid itself should be at least every second year.

 

I will second Dylan in recommending braided lines, since they flex less. Also, they are often less expensive than the OEM brake lines :)

Try squeezing a brake line with your hand, while operating the brake with the other hand - you should feel a clear flexing with non-braided lines.

 

 

Kai

Link to comment
Share on other sites

I was thinking more about this thread something also to consider is the your brake lines are they braided lines or OEM? Braided lines in my opinion should be fitted, if your upgrading your brake package, as this does help to stop brake fade. If Im getting this wrong someone please pick me up.

 

With the OEM lines when they get hot they expand which in turn causes the brake lines and fluid to loose pressure making the brakes feel like you need to squeeze even harder to get the stopping power you want (which BTW doesnt happen), could be another reason why your getting arm pump maybe not.

 

Plenty more technical people in here that can explain this to us better than I can.

 

Dylan

All brake lines (OEM or aftermarket, braided or not) should be replaced at least every four years, due to the UV radiation causing the plastics to deteriorate. The brake fluid itself should be at least every second year.

 

I will second Dylan in recommending braided lines, since they flex less. Also, they are often less expensive than the OEM brake lines smile.gif

Try squeezing a brake line with your hand, while operating the brake with the other hand - you should feel a clear flexing with non-braided lines.

 

 

Kai

 

Thanks Kai, positive reinforcement lets me think I sorta know what I'm on aboutsmile.gif

 

So seeing as we rarely use the rear brake, going off the schools teachings, is it worth changing it to a braided line? Probably about to go off topic but what would be the best braided lines to get? What would be the "Ultimate" brake upgrade?

 

Dylan

Link to comment
Share on other sites

So seeing as we rarely use the rear brake, going off the schools teachings, is it worth changing it to a braided line? Probably about to go off topic but what would be the best braided lines to get? What would be the "Ultimate" brake upgrade?

Dylan,

 

I don't think it's worth changing to a braided line for the rear brake, unless you're going to change it anyway.

 

Case at hand: my Yamaha R6 2008 has braided front brake lines, but the rear brake line is stock. I'm going to replace it with a braided line this winter: not for performance, but because the PP Tuning rearsets moves the brake attachment point 10-15cm back, so the stock brake line is ridiculously long.

 

As for which are "best" - I don't know. They're all good enough to me not to bother with getting the "best" ;)

 

 

Kai

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
 Share

×
×
  • Create New...