Jump to content
StevenAthas

Blip, Downshift With Brake Applied

Recommended Posts

Reduced engine braking with a slipper clutch? Count me out!

 

I find it interesting in the moto world that having some driver aids is acceptable by enthusiasts and then in the auto world they're all looked down upon (power steering I guess has fairly accepted). I come from a big auto background, so my first instinct is to think that all the slipper clutch guys are just being a bunch of nannies. :P

 

I remember I was having trouble with downshifts when I first started riding, but after several weeks of riding I swapped to "GP shifting" and suddenly I was a pro (maybe the wrist and ankle rotating in the same direction helped my timing?). But now when I ride other bikes with normal shifting, I have no issue; probably because moto controls are no longer foreign to me.

 

You surely can practice downshifting under braking on the street. You can do it under low braking conditions. Just like learning heel-toe in a car on the street, it may be a pain in the ass at first, but you'll eventually get it, and even if not completely, you'll most likely have no trouble at racing speeds as less finesse is required.

 

Don't give up! You want to be able to ride any bike on the track. How unfortunate would it be to be given a chance to ride some sweet bike on the track and then be disappointed that you can barely get around the track because you just don't know how to deal with a normal clutch?

 

Just my opinion ;)

Share this post


Link to post
Share on other sites

Please refer to Eirik's new thread "Coordination", and just count your blessings...

 

Speaking as one of the "nannies"....I am actually a bit skeptical about how many people who claim to be expert blippers / downshifters under braking can actually pull it off under truly high-effort near-threshold front braking. That is a pretty difficult trick. Sure, with moderate braking as on the street maybe you can be all fancy and rev-match your downshifts, nice and pretty. But what about when you have to bang out three downshifts quickly in the braking zone when you have come in a bit hot for a tight corner with the back wheel nearly in the air? Maybe you can do it...but I am skeptical that it is a common talent. There is a reason that most serious race bikes run slippers.

Share this post


Link to post
Share on other sites

One observation i have made - Moto3 and Moto2 guys just dump the clutch after downshifting.MotoGP guys, specially Rossi let the clutch out gently at the end.Just slow down the release the last few millimeters.

Share this post


Link to post
Share on other sites

Please refer to Eirik's new thread "Coordination", and just count your blessings...

 

Speaking as one of the "nannies"....I am actually a bit skeptical about how many people who claim to be expert blippers / downshifters under braking can actually pull it off under truly high-effort near-threshold front braking. That is a pretty difficult trick. Sure, with moderate braking as on the street maybe you can be all fancy and rev-match your downshifts, nice and pretty. But what about when you have to bang out three downshifts quickly in the braking zone when you have come in a bit hot for a tight corner with the back wheel nearly in the air? Maybe you can do it...but I am skeptical that it is a common talent. There is a reason that most serious race bikes run slippers.

 

 

I find it to be a LOT easier to blip under heavy braking when using clutchless downshifts. When not using the clutch, there is less of a blip required and it is much quicker and you don't have to worry about how slowly/quickly to let out the clutch. I do routinely come down 2 or 3 gears under heavy braking into corners. However, due to a lot of good training from CSS on technique and visual skills, I am not in panic -braking mode, just very hard braking - enough to lighten or lift the bike wheel - but it does not feel frantic or rushed.

 

There is a video on the CSS website showing Will doing REALLY fast downshifts while braking, a good real-life example of how fast it can be.

Share this post


Link to post
Share on other sites

One part is many try and downshift too early. Brake first, scrub some speed, then downshift (the blips won't have to beas high for one). Take any unneeded throttle cable play out, that can help. With a slipper clutch, and relying on it, one can still overrev the engine. False neutrals can be a symptom of mis-adjusted gear lever.

Share this post


Link to post
Share on other sites

I'd really love to learn how to do this, but have never managed it. I don't even understand the physics.

 

Clutchless upshifts no problem. You back off the throttle a smidge and that "floats" the dogs gears in the transmission so there is no pressure on them and they can slip apart, allowing you to rotate the drum with the shift lever.

 

But how, physically, is one revving the engine on a clutchless downshift? Before the dogs disengaged, if the engine was revved the bike would surge forward. So is the the blip revving the engine between the time (0.2 s maybe) that one set of dogs disengages and the next set engages, as the shift drum is rotating from one position to the next? So you are pressing down on the shift lever and twisting the throttle simultaneously? It seems like you must momentarily be in a false neutral of sorts if the engine can rev without the bike jumping forward.

Share this post


Link to post
Share on other sites

YellowDuck, this is how I do it - and I'm happy to get critical feedback if I could do this better:

 

I stab the brakes and start slowing the bike down at my breaking marker. Then as the bike slows I preload the shift lever enough so that when I blip the throttle, it snicks into the lower gear and because I'm on the throttle a bit, it matches revs (more or less) with the speed. The tranny is loaded initially by the engine braking and by preloading the shifter just prior to the blip, it's set to shift when the blip unloads it from the engine braking. It works like a charm on the S1000RR though as I said earlier in this thread, I'm still working on holding firm and consistent brake pressure when I blip. I'll sometimes release the brake a bit for the blip and I end up slowing more erratically than constantly. This doesn't happen every time for me but often enough that I was starting to think about going back to the clutch especially when I want to drop 3 - 4 gears like when coming off a long straight into a hairpin.

 

All of my downshifts in this video that I posted in another thread are clutch less:

http://youtu.be/lX0pxXMDF5g?list=UU1QkXTbxY9px_OVg0BX8Hig

 

What I'm hearing Hotfoot say is to just keep working on my blipping technique until I iron out the occasional glitches I'm having. Have I got that right?

 

Wes

Share this post


Link to post
Share on other sites

It is basically the same concept in the opposite way - you are taking the engine braking pressure off the gears. When you are slowing down using the brake, with throttle off (and the clutch NOT pulled in), the rear wheel is 'driving' the engine via the transmission which is putting pressure on the gears (in a DEcelerating direction). The drag from the engine is "engine braking". The engine is being forced to stay revved up by your rear wheel speed, NOT by the throttle. When you blip the throttle, you are giving the engine enough throttle to MATCH the rear wheel speed (instead of resisting it) so you relieve that pressure on the gears and the bike drops easily into the lower gear. If the bike lurches forward, the blip was too big or too late. And yes, the blip and shift are simultaneous - just a little blip is enough to relieve the rear wheel drag on the engine and allow the shift. The engine does not actually rev UP a significant amount, you are just adding enough throttle to stop the RPMs from being forcibly slowed DOWN so hard by the rear wheel. Exactly the same (in opposite direction) of what you do when you dip the throttle to upshift - you are just taking the pressure off the transmission so it can shift easily.

 

If, however, you were to pull in the clutch, you disengage the transmission so the engine speed can fall off rapidly (RPMs drop), so you have to do a bigger throttle blip to rev it back up to match the rear wheel speed of the lower gear, plus you are guessing at what the rpm should be to match the wheel speed. With clutchless, I find it easier to know how much of a blip is needed; I can only explain that by saying I have some sense of how much throttle it would take to go from decelerating (engine braking) to that point where you feel the chain start to engage to accelerate. With the clutch engaged the RPMs fall off fast and that changes how much blip will be required, especially if you are not super quick to pull and release the clutch, which can make it more difficult to judge.

 

Does that make sense?

Share this post


Link to post
Share on other sites

YellowDuck, this is how I do it - and I'm happy to get critical feedback if I could do this better:

 

I stab the brakes and start slowing the bike down at my breaking marker. Then as the bike slows I preload the shift lever enough so that when I blip the throttle, it snicks into the lower gear and because I'm on the throttle a bit, it matches revs (more or less) with the speed. The tranny is loaded initially by the engine braking and by preloading the shifter just prior to the blip, it's set to shift when the blip unloads it from the engine braking. It works like a charm on the S1000RR though as I said earlier in this thread, I'm still working on holding firm and consistent brake pressure when I blip. I'll sometimes release the brake a bit for the blip and I end up slowing more erratically than constantly. This doesn't happen every time for me but often enough that I was starting to think about going back to the clutch especially when I want to drop 3 - 4 gears like when coming off a long straight into a hairpin.

 

What I'm hearing Hotfoot say is to just keep working on my blipping technique until I iron out the occasional glitches I'm having. Have I got that right?

 

Wes

 

While what you are describing DOES work, the school mechanic Will, who knows these bikes extraordinarily well, says it is hard on the transmission to pre-load the sifter and he does not recommend it. So you might want to work towards getting the blip and shift into one motion that does not include preloading the lever, just for the sake of longevity of your transmission.

 

Sounds like you have the skill mostly under control, but if you are having trouble getting the braking while blipping consistent, I'd suggest finding a big safe parking lot area and breaking it down into steps for practice. Practice blipping and downshifting, without brakes, in a straight line. Then when consistent, move up to doing two downshifts per run, then three (if you have room). When that feels really comfortable and consistent, go back to one shift per run and add light braking, then more aggressive braking, then multiple shifts, or whatever gradient feels comfortable for you. I think you will get a lot more out of isolating the parts of this skill and practicing in a straight line with no other distractions than you can get trying to practice on a racetrack or road, with turns and traction and other riders, etc. to think about.

 

If you have the opportunity to come to a school you can have a coach work with you on this specific skill in an off-track drill. :)

Share this post


Link to post
Share on other sites

If you have the opportunity to come to a school you can have a coach work with you on this specific skill in an off-track drill. :)

Holy hell, you can do this at the school? Hmm...

Share this post


Link to post
Share on other sites

Yes the school has a specific rig designed to allow you to practice holding constant brake pressure while bliping the throttle, it's a a neat set up, while I haven't actually been coached on it, I have sat on the thing and played around with it

Share this post


Link to post
Share on other sites

One part is many try and downshift too early. Brake first, scrub some speed, then downshift (the blips won't have to beas high for one). Take any unneeded throttle cable play out, that can help. With a slipper clutch, and relying on it, one can still overrev the engine. False neutrals can be a symptom of mis-adjusted gear lever.

 

Been there. Done that. One on of your 2012 BMW's none the less. Never overreved it but it certainly screamed at me doing it the wrong way. It was really distracting. I have heard as well you can easily get sucked in if you get a false neutral by downshifting first.

 

Lately for time management purposes I have been using the brake first technique. It's not the best way but it works quite well. Going back to braking and downshifting at the same time is on my list. I find at least for me doing both at the same time eliminates one thing I have to think about on corner entry. With one less thing to check off the list I could wait later before the entry into the corner.

Share this post


Link to post
Share on other sites

Yes the school has a specific rig designed to allow you to practice holding constant brake pressure while bliping the throttle, it's a a neat set up, while I haven't actually been coached on it, I have sat on the thing and played around with it

 

I know one additional thing I'm going to do next year at Barber if it's available.

Share this post


Link to post
Share on other sites

It is a bad idea to preload the shifter, but hotfoot has explained the process very well.I think people should put up videos if possible so that we can compare technique.

Share this post


Link to post
Share on other sites

 

 

Wes

While what you are describing DOES work, the school mechanic Will, who knows these bikes extraordinarily well, says it is hard on the transmission to pre-load the sifter and he does not recommend it. So you might want to work towards getting the blip and shift into one motion that does not include preloading the lever, just for the sake of longevity of your transmission.

 

Sounds like you have the skill mostly under control, but if you are having trouble getting the braking while blipping consistent, I'd suggest finding a big safe parking lot area and breaking it down into steps for practice. Practice blipping and downshifting, without brakes, in a straight line. Then when consistent, move up to doing two downshifts per run, then three (if you have room). When that feels really comfortable and consistent, go back to one shift per run and add light braking, then more aggressive braking, then multiple shifts, or whatever gradient feels comfortable for you. I think you will get a lot more out of isolating the parts of this skill and practicing in a straight line with no other distractions than you can get trying to practice on a racetrack or road, with turns and traction and other riders, etc. to think about.

 

If you have the opportunity to come to a school you can have a coach work with you on this specific skill in an off-track drill. :)

 

 

That's exactly the feedback I was looking for. I was wondering if this was hard on the transmission and it sounds like it can be if the shifter pressure is not closely correlated with the blip. I'm definitely coming back to a camp next spring for level 3-4 but you've given me a drill I can work on for this in the mean time to get more consistent with the brakes. Thanks!

 

BMW is making available on the '15 bikes a shift-assist that includes the blipper for clutch less downshifts. I guess at some point in the future when the school upgrades it's bikes, some thought will have to go in to if this is available of the student bikes. I can see arguments both ways for having/not having it available since a lot of students will be going back to their own bikes that don't have blippers.

Share this post


Link to post
Share on other sites

 

 

Does that make sense?

 

Yes perfect sense. Thanks to you and PittsDriver too for taking the time to explain in to me. Bike is away for winter now but this will be on my list of skills to try to acquire during practice next season. Chances are I will end up grenading my gearbox but hey, the bike has had a long and productive life....

Share this post


Link to post
Share on other sites

Blipping when downshifting worked for me but not always great. I saw the vid of Joe Roberts on this thread and tried it the way he does (2 middle fingers on the brake). Works well for me ! OK, it can probably still improve but it is already so much better !

Share this post


Link to post
Share on other sites

Correct on not pre-loading the shifter, too far in advance. On some bikes this (done for a while) can cause parts to wear in the transmission...my brother had to replace 2nd gear from doing this too much. Again...it's just the pre-loading that is the issue, not the clutchless shifting.

Share this post


Link to post
Share on other sites

There were two keys for me in learning to blip the throttle while on the brakes:

 

1) Using just my forefinger and middle finger on the lever, leaving my other two fingers and the palm of my hand in contact with the throttle grip, allowing me to twist it with good feel/control.

 

2) Grabbing the lever as close to the tips of my fingers as possible while still being able to get the necessary brake pressure. This gives you more freedom of motion to twist the rest of your hand. If you grab the lever near the base of your fingers it makes it much more difficult to twist the throttle for the blip.

 

I also felt it was much more difficult to get an accurate blip at slower speeds/RPMs (say, 4-6K RPM range) than when doing it at higher revs. It can certainly be done, it's was just more difficult to get it right.

 

Hopefully this can help some of you.

 

Cheers,

Benny

Share this post


Link to post
Share on other sites

Been practicing this.. I'm still putting too much input on the brake as I blip. I find that as I twist the throttle to blip, I inadvertently release the brake a little bit. I've tried to counter it by squeezing the brake a little tighter and keeping the pressure on my two fingers but then i notice that my blip is all off (either too much or too little).

 

Not sure if shorty levers will help with this but I will be picking up a pair soon.

 

To be perfectly honest, I was really frustrated at the end of the day trying this out. I got it right a few times, but far less than preferred.

 

One thing I noticed, was that when downshifting clutchless and on the brake using a blip, it felt way more smooth and a little more consistent than when I was clutching. I have to blip much less which helps because I'm not applying too much pressure on the brake as I blip.

 

Definitely still a work in progress. Been one of the more challenging aspects of riding that I've encountered thus far.

Share this post


Link to post
Share on other sites

It sounds like you're making progress. At least you can get it sometimes so we know you can do it. You'll get there. The blip is very much a muscle memory/habit thing. Does repetition help that? Could you practice that singular action just sitting on a parked bike a couple hundred times to get it down a bit better before your next ride?

 

Also, I wouldn't expect shorty levers to help this. If anything, the shape of a different lever might help, but not necessarily the length. New levers cost about as much as some track days. Practice in the garage is free. You choose which would be more helpful to you.

 

Cheers,

Benny

Share this post


Link to post
Share on other sites

Benny is correct, the profile and angle/height of the lever matter more.I haven't tried shorty levers, but i found how far out the lever was and what kind of angle it was set at made a difference.

Share this post


Link to post
Share on other sites

It sounds like you're making progress. At least you can get it sometimes so we know you can do it. You'll get there. The blip is very much a muscle memory/habit thing. Does repetition help that? Could you practice that singular action just sitting on a parked bike a couple hundred times to get it down a bit better before your next ride?

 

Also, I wouldn't expect shorty levers to help this. If anything, the shape of a different lever might help, but not necessarily the length. New levers cost about as much as some track days. Practice in the garage is free. You choose which would be more helpful to you.

 

Cheers,

Benny

That is a great point. I'd still like to get shortys for the look but I definitely see more value in a track day where I can work on many other things. Thanks for chiming in.

 

Benny is correct, the profile and angle/height of the lever matter more.I haven't tried shorty levers, but i found how far out the lever was and what kind of angle it was set at made a difference.

I'll adjust the distance from the clip-ons and see if anything changes. Thanks for the feedback.

Share this post


Link to post
Share on other sites

watch this video:

 

 

 

Nice riding but...you can see the brake lever move on every downshift. Maybe this isn't enough movement to have an effect with his braking setup, I dunno. But it reinforces my feeling that it is pretty hard to modulate braking perfectly when you are blipping shifts.

Share this post


Link to post
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...

×
×
  • Create New...