Hotfoot
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Posts posted by Hotfoot
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Yea I have watched that video and it is impressive. Hotfoot- Would you say it would be better to use the clutch method until I have a slipper clutch installed to reduce risk of damaging anything?
The slipper clutch really kicks in if you hold the clutch in so long that the RPMs really drop, then let the clutch out quickly - it will keep your rear tire from locking up (hypothetically) while the engine speed catches back up to wheel speed. I honestly don't know whether it would make any difference on clutchless shifts at all; I ride bikes with both the slipper clutch and without, I can't tell any difference. The only time I notice the slipper is if I use the clutch to downshift, which I really only do if I've made a gigantic error and I'm trying to recover.
Before I learned clutchless downshifting I thought the slipper clutch was a godsend but now I am just fine riding a bike without one.The only time I've ever had any grinding or scary shifts was when I tried to lightly feather the clutch, pulling it only partway in, and shifting. You can get some gnarly sounds doing that, if you arent quick enough or screw up the blip. I've also heard of people doing damage by pre-loading the shifter (Will HATES it when people do that) or stomping down hard on the shifter to try to force it - that can bend the lever. But a regular clutchless downshift should just click right in, no drama.
On every bike I've ridden (which includes dirt bikes, a cruiser and even my little old YSR) it either shifts, or it doesn't. If you get the timing wrong it just won't change.
This is just my opinion and my personal experience but I think the easiest and safest way to to it is the way I described earlier in the thread - in a high gear, at low rpm, accelerate, then left off the throttle and RIGHT when you let off, downshift. It should just drop right into the lower gear. After you get that timing, you can go back and add the blip so you can shift while slowing down.
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But I cannot see anyone able to match 4-5 downshifts as rapidly combined sans clutch. If somebody can show me, with a slipper of course, they can go from 200 mph in 6th down to 2nd in well under 2 seconds and way before the speed has come down without using the clutch, I promise to be very impressed
2 seconds is a long time. Getting 4 downshifts in 2 seconds, clutchless, should be something a club racer could do. (Maybe not 5, though - first gear can get dicey unless you have a bike with a REALLY tall first gear.)
As far as an actual example goes, you can see Will do it in the track demo videos on the Superbike School website. For example in this one at Streets:
and the one at VIR (the only place I could think of where you are near 200 mph and downshifting all the way to 2nd)
you can hear Will downshifting 4 gears well within 2 seconds without using the clutch.
Getting the engine slowed down between shifts could be a limiting factor, but that is a braking effectiveness issue; I don't see how adding in the clutch would help with that, overrevving the engine is overrevving it, it would be hard on the clutch and can be catastrophic to the engine. And you can overrev the engine and blow it up even if you are using the clutch; I don't know whether or not it is possible to overrev the engine on a clutchless downshift, I think on most bikes it simply would not shift.
Maybe in the ultimate top level bikes, they have electronics to protect the engine and gearbox? Or maybe they just have REALLY GREAT brakes.
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Well, if it doesn't work for you, it doesn't work for you - but personally I am much quicker at clutchless downshifts when racing, on bikes with or without a slipper clutch. I prefer clutchless because I never ever lock up the rear tire, and I've never have any gears grind or get damaged. It's really easy, in race conditions, to lock up the rear tire when releasing the clucth (even when you do it fast or only partially engage it) but going clutchless totally eliminated that problem for me. Once you get the timing, it is quite reliable and also eliminates the possibility of accidentally going down two gears.
I'm not sure I understand the logic where someone said there is no way clutchless could be faster - how does adding the clutch motion make it faster than just shifting?
If you search the forum on this topic you can find considerable info on this, including where Will chimes in and explains why it isn't hard on the transmission. He's had many years of maintaining fleet bikes and race bikes with and without slipper clutches and he is all for clutchless downshifts - he certainly wouldn't allow/encourage the coaches to do it if it was bad for the transmissions!
There is also a video on the website showing him doing lightning fast downshifts without the clutch - and he holds track records, his race experience is nothing to sneeze at.
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I was practicing some more clutchless downshifting, I have a quick shifter so I don't need to use the clutch anyway for that so I was just focused on the clutchless downshifting. My timing still seems a little off and I am not very smooth at it, this is how I would describe what I am doing because I don't want to get into the habit of doing it wrong.
1. start to put pressure on the shifter
2. push down
3. blip throttle
I've always been told that pre- loading the shifter is bad for it. I know for sure the S1000rr's don't like it, it confuses a sensor in the transmission. The idea of the blip to to relieve the load on the gears and match the RPM so the shift is smooth and easy, so you need to do it at the SAME TIME you shift. Getting the timing right is the hardest part.
On most bikes, there is a way to practice the timing that you might find easier: if you accelerate, then let off the throttle and downshift (make sure you press the shifter RIGHT when you let off) the bike should drop easily into the lower gear. It can help if you think of the throttle and shifter as connected, so you move them both at the same time. By accelerating (gently is fine) then letting off, you release the load on the gears but shift before the RPMs drop, so you don't have to blip it.
This is most easily done in a high gear at low rpm - for example shifting from 4th to 3rd at, say, 4-5000 rpm (this will depend somewhat on what type of bike you ride!).
Doing it that way can give you a sense of the timing; once you get the idea you can try it the more typical way, where you are decelerating, then blip the throttle to match RPMs to get the downshift. In high gear with low rpm it only takes a small blip - too much, or too early, will make the bike surge forward. If you don't blip enough or if you are too late, it just won't change gears. Done correctly, a down shift feels remarkably quick and smooth, no drama, it just clicks in.
Do not press harder on the shifter to force it to change, if it doesn't shift easily the timing was off and trying to force it will not help.
It's easier on some bikes than others, but it's worth learning - once I got it figured out, I started doing it on all my bikes, on and off the track and even on the dirtbike, it's great, quicker and easier.
If you can get to a school, we have an off-track drill for this, a coach can work with you one-on-one.
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Why would you want to downshift without the clutch? What advantage do you feel there is in that? The potential for mechanical damage is pretty high.
This has been discussed a lot on this forum, do a search on clutchless downshifting, you'll find a lot of info! Here is a link to on of the threads: http://forums.superbikeschool.com/index.php?showtopic=2115&st=0&p=16613&hl=+clutch%20+downshift&fromsearch=1entry16613.
Clutchless downshifting is more common than you might think, most of the coaches at the school do all clutchless downshifts with no ill effects on the bikes. Th advantages are that for most riders, once they learn to do it, it gets the shift done much more quickly than using the clutch, plus it means one less control to worry about. Letting out the clutch on a high speed downshift can take a lot of attention.
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Do you guys use the race day records that are in the back of the twist 2 book or do you have your own style of notes keeping? I am thinking about getting a binder and printing off some sheets to keep track of my progress and how different setups give different results.
What about note keeping during/after a CSS level? I haven't attended a class yet, I was supposed to attend the one this month on the 27th at willow but I can't take the time off work so I had to reschedule. I think notes comparisons really help keep track of everything but organizing it in a way that it all makes sense helps too!
I keep two separate binders, one for maintenance/repair/suspension settings info, and another for track notes with reference points and tips recorded for different tracks and days I've ridden.
In my maintenance records I keep track of the engine hours (I finally got an runtime meter on my engine) since my last oil change, number of days on my tires, and other maintenance info like when I changed chain and sprocket, checked valves, etc. I also have a list of parts numbers or sizes for certain items and the vendor info so I know where I can get parts.
Recently I've started moving the maintenance records info and part number/vendor list to my iPhone so I have it handy, instead of having to go get the binder out of my race trailer to check my notes. That is going GREAT so far, very useful to have the info at my fingertips.
In my track/race day records book I like to write down the reference points I found, and record my shift points and what gears I was using where, and any other useful track-specific things I learned (like, there is a big bump right before the apex of Turn 4 that is hard to see!) etc. I also write down gains for that day, and I keep a running record of my best-ever laptimes at each track I ride.
Those notes can be useful but I really don't find that I review them very often, I should probably make more effort to do that. Sometimes the track has changed (repaved, etc.) or my riding has changed so much since I wrote the notes that they don't seem very 'real' to me anymore.
I did take notes when I did CSS classes but I find that just having a copy of Twist of the Wrist II handy is a MUCH better way to review the concepts; often I look something up in Twist II, re-read it, then find that I gain a more complete understanding after re-reading it in the book than I ever would have from reading my class notes.
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Wow, some great stuff in here! I'll offer up my own goals - After my next race I have a little time off so I want to get new fairings and paint on my race bike. (NO, I didn't crash it - the fairings that came with it are a bit ragged.)
My riding goal is to improve my mid-corner speed, particularly at one track that has a long left-hand corner leading to a long straight; in my last race I learned that I could be getting through there quicker (either by carrying more speed in, or by getting on the gas harder mid-corner) which would get me to WFO sooner on the long straight. As I tried to go into this corner faster (which involved coming OUT of the prior corner faster) I started using the brakes lightly to set my entry speed, but I finally realized that I really don't need to brake there at all; just calculating my roll-off properly will allow me to set my speed more accurately. Using the brakes there is really just an SR and it is making me slow down too much. So, I'll be doing a lot of no-brakes practice, in my next few track days!
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I thought they all DID have them, I remember Keith saying you see them on all the bikes when you walk around the paddock. Have you seen pro bikes without them? Could they just be using clear or black ones that aren't highly visible?
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I can see your picture. Are you on a mobile device? The website shows your normal avatar photo if you are on a PC but a different one if you are on mobile - I you haven't set up that additional one maybe it appears blank.
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I'm not sure if this is the right section for this, but here's a general dicussion question... what's your goal for your riding in the next 12 months or so? Is it to get to a school, get a new bike, or try out a trackday? Find a better place to ride, prep your bike for racing, get better safety gear, manage your cycle budget better?
What about your skillset, do you want to corner faster, lean it over farther, improve your sense of speed, lean how to choose better lines? Do you want to steer more effectively, be more confident in traffic, get faster than your buddy?
I'm curious to hear what you guys are thinking about, what sort of goals you are setting for yourself.
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How often would you say you trail brake into a corner? I didn't really understand trail braking until I just watched the TWOT2 again, it's so true that every time you watch it you learn something new or it clarifies something as well. I always thought trail braking was when you used the rear brake and slid the rear tire into the turn or is that just another form of trail braking? After watching the video I realized it's using the front brake and easing off into the turn once you have reached your turn entry speed.
I know trail braking when the track is wet is generally not ideal but I am sure with practice it could be done precision. Or would you avoid trail braking at all when the track is wet? If I am not mistaken in the video it says trail braking into the turn is the preferred method of braking.
Different people define trail braking different ways, as you are discovering! So let's clear up some terminology first. Let's call the "turn point" the place where you actually make your steering input. Most people consider "trail braking" to involve continuing your braking action PAST the turn point and often up to the apex of the turn, so you are braking while leaned over and turning the bike, so let's go with that as our definition. (I would also assume this to be ALL front brake, and I agree with utahphunk that I'd call using the rear brake to slide the back around "backing it in".)
There have been a lot of discussions about this so if you do a forum search you can find some great discussions about the trail braking and when it is useful.
Trail braking can be a dicey proposition because you are putting a lot of load on your front tire while leaned over.
To answer your question, I rarely trail brake because I very much prefer to have my entry speed set at my turn point. I like getting my hard braking done early with the bike as close to vertical as possible, tapering the brakes as I approach my turn point to accurately set my entry speed, and ideally releasing the brake at the exact moment I turn the bike, so that the front suspension stays compressed throughout. I do sometimes trail brake into decreasing radius turns that have a wide, high speed entrance, or if I am trying to make a very late pass on the brakes (but there is a risk of being passed on the exit, if the other rider is quicker to get back to the throttle).
I never trail brake on the street becuase I'd be concerned about hitting something slick (or even a big bump!) on the road while leaned over and on the brakes.
This year I gave trail braking a really good try, because I'm riding a bike that is lightweight and I can get amazing grip with the front tire. I made a concerted effort to brake later, deeper into the corners, and carry more entry speed. I was trying to lower my laptimes and also prevent anyone from passing me on corner entries. Here's what I found: I wore out my front tire prematurely, at one point I overheated my brakes by braking more gently and for longer (essentially dragging the brake), and I had more moments where I came close to falling than I've had in 5 years. I found myself bracing my arms and couldn't get low and relaxed entering corners so my steering was less effective and I was having to lean the bike more, and I was REALLY overloading the front (leaning plus brakes plus stiff arms, bad plan!).
I had convinced myself that corner speed was so critical on this lightweight bike that I HAD to trail brake or I would be passed on turn entries in my races - because it seemed like everyone ELSE was trail braking. However, in the last practice day before my race (a couple of weeks ago), I came so close to crashing so many times that I decided to quit trying so hard to trail brake and just work on getting accurate entry speeds and good quick turns, so I wouldn't crash!
Guess what happened? I stopped trying to trail brake, and my laptimes came down two seconds! I won both my races. I had one particularly fast rider that kept coming up on me at the entry of one of the turns where I had been trail braking (this is what I was afriad of!) and he managed to pass me on the entrance twice - but both times I got back on the throttle earlier and passed him right back on the exit. He could get INTO the corner faster, but he couldn't get OUT faster.
So not only did I go faster overall, I was MUCH more in control, the bike handled better, my tires didn't wear as much, and I didn't have any "oh sh*t" moments even though I was racing and riding as fast as I could. It was way, way, better in every way.
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I'm surprised not to see more feedback on this topic. No one has any special lotions, potions, or secrets to prevent sore muscles or refuel after hard exercise, or exertion on really hot days? No special supplements or vitamins, jacuzzi soaks, or Advil?
I sometimes use a hot bath or Jacuzzi soak to prevent sore muscles. That seems to work well, when I have the time/opportunity to do it. However, my biggest challenge is getting properly rehydrated after really hot days at dry-climate tracks; it seems like I stay thirsty (and cotton-mouthed) for a couple of days, no matter how much I drink (water or Gatorade). I've started taking some potassium at the end of the day, to see if that helps - so far it seems like it does.
For my horses I feed an electrolyte supplement that can be given before and after exercise, it's a powder. Anyone done anything similar for yourself, with good results?
This doesn't just have to be about riding, whether you climb mountains or run marathons or work in construction, if you have ideas that work, I'd like to hear them!
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I attended CSS LVL 1-2 during the weekend of September 15 & 16 and I am trying to figure out what tire pressure was set when I brought my bike through tech...I was on a white Ducati 848. Tires used were Pirelli Diablo Rosso Corsa...<br style="color: rgb(28, 40, 55); font-size: 13px; line-height: 19px; background-color: rgb(250, 251, 252); ">Thanks Fred
I remember your bike. I think we set you at 31 front 30 rear, cold. As I recall recommended track pressures for those tires are something like 31-34 front and 28-32 rear.
How did you like those pressures? I haven't ridden on those but I've heard they have a softish sidewall and some folks run them on the higher side of the recommended pressures to get more feedback.
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Did you have the oil changed recently? Some additives in (car!)-oils that are supposed to reduce friction are poison for motorcycle clutches.
Yes, it gets changed often because I am racing it, it was changed right before my race. It was done by a motorcycle mechanic, hopefully using the right oil, but I can check. What should I look for as a bad oil or additive for a race bike? This bike has a CR250X dirt bike engine.
Thanks for the tip about the oil as something to watch for.
I'll be changing the clutch anyway due to a high number of hard hours I've put on it, it's almost certainly due for it.
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You got it right about the slip occuring at the torque peak in a high gear, next it will just start slipping at high revs. I wouldn't bother measuring or inspecting givin the amount of time you have on it alone! I would replace all the friction and pressure plates along with the springs. There will be some bigger pressure plates and you may need a few of those so you can set the pack hight with all the new parts. When you have it apart make sure the friction plate ears haven't beat grooves into the clutch hub teeth, that can cause the clutch to act funny.
Yeah, I was thinking about that - I do have quite a few hours (and a number of race starts) on that clutch now, and don't know how many it had on it before I got it.
Ok, thanks for the advice, I'll get it done before the next races.
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There is only two things that can cause rpm to jump rapidly; slipping or extra acceleration. If acceleration is constant, then something must give. AFAIK, it cannot be something in the gearbox, because it would jump, not just let the rpm down. Nor can it be the final drive chain because it's the same thing. So we're left with the clutch or the tyre. However, the tyre would be most likely to slip in the lower gears and the clutch in the higher gears. If engine torque is at its peak around 11k, it may be the clutch being just a bit too weak to withstand it in 4th gear and higher. If you do not notice it in 5th and 6th, it could be that due to the spacing being tighter that you do not let the rpm getting that low under acceleration in those gears.
I should clarify that it is a 5 speed bike, and 5th gear is a weak gear that doesn't pull as strongly as 4th - I don't use 5th much and don't shift into it until over 12K. So your answer makes a lot of sense, it is certainly possible that around 11K is the peak torque and the hardest work the clutch ever has to do is in 4th gear at that RPM.
So... currently the bike pulls strongly and my starts are good, so the problem may not be immediately obvious to a mechanic - is there a way to check the clutch to see if it is getting worn or weak, to try to confirm it as the source of the problem?
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Hi there, I've got a question about my Moriwaki, which has a stock Honda CR250X motor in it. Recently I've noticed that just under 11,000 RPM, when I am accelerating, the engine sounds like it revs up suddenly and I see the tach jump up a few hunderd rpms, then continue its normal smooth increase. It ONLY does it right below 11,000 rpm. (Redline is around 14,000.)
At first I though maybe I was spinning up the rear wheel but it happens even with the bike straight up and always at the same rpm so I don't think that's the problem. I've only noticed it (so far) in 4th gear, not sure if it does it in other gears.
What could be causing this? Could the clutch be slipping, or some other transmission issue?
The power feels consistent through the sudden rev - there might be a very slight hesitation but definitely not a surge in power - it is just the sound and the tach movement that is catching my attention and making me wonder if there is a problem brewing.
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As I recall there is a VERY BIG difference between the "street" Power Pure and the track version sold by track vendors. The round profile is a more street oriented tire that is a lot less sticky on track. It's weird that they call both versions the PowerPure, quite confusing.
Yeah, they should at least call the track version of it the Power Purer or something to make things less confusing.
Amen, or how about Mo' Power. Or RACE Power. Or Pure Race. Or Pure Race Power. Or... Jeez, this is easy, I can't believe they couldn't come up with other ideas!
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I recently took my very first trackday/clinic - woohoo! Super stoked about it, especially considering it was raining cats & dogs all day, yet I was riding faster & more confident than ever before!
Now, towards end of the day I realized I have a problem with braking. Sometimes I would approach the turn entry point a fast enough to require some hard braking, and once I managed to lock it up. It felt like bike was sliding, but was not unstable - ie it kept going forward with no noticeable wobble. I released front brake pressure a bit and it stabilized itself (obviously I was not using rear brake at all).
Coach was riding behind me, and didnt notice anything wrong, and wasnt able to offer any explanations. I think my problem is not fully releasing the throttle while braking & downshifting. This sometimes happens to me whenever I start to push the envelope a bit - not exactly fear but just insufficient attention towards full throttle rolloff. Obviously I need to work on my brake/down technique.
I am trying to understand what happened... could it be that my front tire was not locked, but rear was spinning & loose due to the throttle not being completely off? I was in 3rd gear for pretty much all turns, Kawi Ninja 650 (all stock).
Thanks!
Peter
I was chatting with Will recently and he mentioned something that you might want to check on - he said that sometimes a rider's glove can be a bit too loose in the palm, making it hard to fully release the throttle while braking. Apparently it can feel to the rider as though he has released the throttle but the material in the palm of the glove (which is usually a high-grip material) keeps the throttle from going closed. I'm not sure if the happens because it creates a fold in the leather or just because it is loose, but when I read your post I thought it might be worth mentioning, something to watch for. I have had it happen to me and I didn't know why; after talking to Will I think a too-big glove was the actual cause.
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California Highway Patrol says: "Lane splitting is permissible but must be done in a safe and prudent manner."
That means that it is the officer's discretion - if he/she thinks you are going too fast for conditions or riding unsafely, you can get a ticket, but being in between lanes is not, in itself, disallowed.
Lane splitting here in LA is very, very common - on a typical rush hour commute, if traffic slows or stops, lots of motorcycles will come by in between lanes, and of course the CHPs do it all the time, too.
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As I recall there is a VERY BIG difference between the "street" Power Pure and the track version sold by track vendors. The round profile is a more street oriented tire that is a lot less sticky on track. It's weird that they call both versions the PowerPure, quite confusing.
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How does one get good at anything?
We get some form of this question often, "How can I get ___________ good?" Whatever the blank is: drag a knee, use a lot of lean angle, ride as fast as one's friend, a coach at the school, etc.
Is it all natural talent, big cajones, mental toughness, education, seat time, the latest bike and tires, cool suspension bits, good advice from friends?
What about other sports/activities, what format of training works there too?
As is obvious to anyone who has been at the Superbike School, we think correct information is a good place to start. Go over the theory, get a solid understanding of it, and there is a priority of information. The information that is most critical is presented first.
In the absence of a school, one could read the material available on the subject. A thorough review of the books and material available would be the next option.
This is first in a series I have in mind, but want to see if the subject piques your interest or not.
Let me know what you guys think on this please.
Best,
Cobie
Well, let's see... I wanted to get good at riding a motorcycle.
Natural talent? No.
Started at a young age? Nope.
Big cojones? Definitely not!
So I guess in my case the answer would have to be good training!!
Thank you CSS, who ever imagined I'd end up racing motorcycles?!?
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I asked the same question the guys from Continental at the June CSS at Silverstone. They replied the most important reason for not running the tyre in the opposite direction is hidden in how the tyre is actually constructed.
Simply put the core of the tyre is made out of a long strip of "rubber". In order to make this strip a circle you have to connect its ends by overlapping them so that one is over the other. The correct direction of rotation of the tyre is such that while rotating it doesn't "hit" the edge of the overlap to eventually cause a critical damage.
That was enough for me to stop flipping tyres
Regards,
Tony
Agreed on this, that is the same thing Will told me. There are different ways to connect the ends, and only certain methods are compatible with being able to flip the tire; for instance if the overlap at the end was cut to a 45 degree angle, you wouldn't want to run it in the direction that could peel back the end of the junction.
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Oh wow I didn't know the GP bikes had that kind of technology! Does anyone have a picture of this body position? It kinda makes sense but of course visual is always better, the video didn't show a whole lot.
Photo 4 in the slideshow on the superbikeschool home page looks like a hook turn in action.
Before I learned clutchless downshifting I thought the slipper clutch was a godsend but now I am just fine riding a bike without one.
Race Day Records
in Cornering and Techniques
Posted
It's not particularly well organized. It's by date, on my riding notes, and by track for maps and laptimes.
The maintenance records are just listed by category (tires, engine, transmission, fuel) then a list of dates of when any major maintenance was done or changes made. Now I've starting keeping that info in a note on my iPhone, so I have part numbers for tires, etc. right at hand any time I needed it.
I also keep a note on my phone with my best-ever laptime at each track, because it feels so good when I get to update it!
Funny you asked about a program to organize this info, I posted a question on the WERA race forum asking if anyone knew an iPhone app for tracking race bike maintenance records and they jumped ALL over me asking what's wrong with good old pencil and paper!
I think you should create an app for us....