| Author | Message | ||
     Pariah |
So I had my third trackday this past weekend at Texas World Speedway (a smooth flowing, relatively fast 2.9-mile road course). I was on my third lap (of the third session), and I thought that I had the tires fairly warmed up, but as I was dragging a knee in a slow speed chicane (the last right before the long straight), I lost traction going about 40mph. I did not touch the brakes and was applying maintenance throttle at the time. Body positioning was steady. Track looked clean and it was sunny and dry (about noon and 90F). The bike and I slid for at least 30 feet, and I spent about half of that rolling. I was fortunate not to have any injuries (save for a bit of abrasion on my forearms and elbows), and the bike was ridable afterwards, though the clutch cover, handlebar, side pod (amongst other parts) took some damage. Easily repairable, though. Frame and swingarm saved by pod and DarkHorseMoto sliders (thank you, Keith!). I think an error I may have made was with tire pressure. I stuck with 34psi front (cold), 36psi rear (cold)... the "stock" settings for the Pirelli Diablo Corsa IIIs. What do you trackday 1125R folks use? My suspension settings are as in the Buell manual, for a 230+ pound load (me with gear and empty stomach). Oh yeah, and feel free to dispense advice. I love getting criticism from this tough crowd...  (Message edited by pariah on September 02, 2008) | ||
| Xb9 |
32F/32R cold tire pressure is what is recommended for track use by Pirelli. Depending on the track surface, temps, your weight, and how hard you are running, this may vary a lb. or two to be optimal. The size of the contact patch is reduced by running the higher pressures, more than likely contributing to the loss of traction. From my experience these tires work better at some tracks than others. Mid-Ohio (smoother surface, less abrasive) they work fantastic. VIR (rough surface, abrasive) after about three laps they go away. Might have been better at VIR though if we could have adjusted the pressures (pre-production demos). | ||
| Jdugger |
I hate TWS. I slid all over the place last time I tried to ride there. For the record, I'm a crappy track rider, anyway, but TWS is slick, has horrible pavement, junk patches all over the place, and generally spooks me silly. Another real slick spot there is the patching in the right hander right before the downhill into the 180-hairpin. I had 3 or 4 front tire slides there (recovered) before I just got off the track and decided that place was not for me. I've seen lots of FM roads in far better condition than TWS. | ||
| Brent1125russ |
My last track day at the start of August, I went 30F/30R cold anticipating the 105F ambient temperature as the day came on, not to mention there is no shade on the track and it was absolutely roasting by 10am. I never checked them hot, but I know out on the track that they were pretty firm after my 2nd session. The track I was riding on (Spokane County Motorsports Park) is a touch more abrasive than Mid-Ohio, and noticed by the end of the day that the back end was a little loose, but the front was still solid. I'm 6'4" and 230lb in gear. I think your tire pressure was just too hard when cold and by your third session those tires were rock hard. | ||
| Fresnobuell |
My suspension settings are as in the Buell manual Anyone notice that the owners manual and service manual have WAY different suspension setting for the 1125r? I mean not even close....I would ordinarily go with the service manual as one would think that BMC had more time to develop the settings, but it calls for making everything stiffer for a given weight. Maybe the SM settings for the track, but I can tell you that they are way too stiff for the street. | ||
| Jdugger |
> Maybe the SM settings for the track, but I can tell you that they are way too stiff for the street That said, they loosen up. I'm at almost 20k my 1125r now, and I'm going to have to add a click to the rear pre-load. I've lost weight, too. The forks are finally compliant and working great, though. This is a bike that improves with riding... | ||
| Fresnobuell |
Once I softened a quater-click on the fork compression and rebound, things are working better--esp. in your typical street scenarios. My front sag is about 25mm, anyone have a recommendation? I have to say that this suspension setup stuff gets me really confused. I WISH that I would have a knowledgeable 1125r person set it up for my weight, just so I could ride a bike that is dialed in for me. ONce I get that reference point, then I would be good as I know what a bike SHOULD feel like properly setup. Right now, I am sorta shootin' in the dark... | ||
| Pariah |
Hey Everybody, Thanks for the feedback... Cheers, T. | ||
| Slaughter |
35mm in the front is better on almost ANY modern suspension. 25mm is pretty harsh. You can dial in the damping a bit if you need it. That'll take more sneaking up on it but the sag in front ought to be more like 35mm (Message edited by slaughter on September 02, 2008) | ||
| Fresnobuell |
Slaughter..Thanks, buddy. Please confirm: 1) I am measuring the sag by using a twist tie on the fork and measuring how far it moves after I mount the bike. Is this a proper way of measuring? 2) I can increase sag by decreasing preload. 3) What you are suggesting will soften the ride, but I can offset if necessary by increasing damping? | ||
| Slaughter |
Nope - you have to: 1 - LIFT the front end off the ground and measure from some fixed point on the bike down to the axle (this is ZERO) 2 - Sit on the bike with ALL your gear... wiggle a bit to overcome stiction. Measure this point. Difference is static sag. By your description, you may be pretty close to 35mm already.
Yes. Realize you are also changing ride height by about 5mm or so. Problem is that one suspension change will have other effects too. (Rear sag should be on the order of 25mm)
If you are ONLY going for a long slab ride, you CAN increase sag a bit without changing damping. Your handling will be off, but it WILL be more comfortable if you just have to cover a boatload of miles. Heck, I'm no expert - this is just stuff that's worked for me and stuff I've taken notes on over time. The zip tie is really useful for measuring compression under braking and is one data point to use when adjusting compression damping AND/OR sag. | ||
| Fresnobuell |
I certainly want to keep things on the sporty side. I mean why have this kind of bike if you going to soften it up? Problem was that the front was so stiff if felt like I was boucing over bumps and even seams in the highway were causing some head shake during high speed turns. Thanks for the help. I am definitely learning...so do you just tighten everything up when you goto the track? i have a feeling that my harsh settings would be good for the track, since it was awesome when the pavement was smooth. | ||
| Pariah |
I followed the settings in the owner's manual... I gotta say, they seem spot on to me. On the street or the track, the bike behaves. Have you tried the OM settings? Probably worth a go... My trackday mishap I attribute to tire pressures (as Brent & David pointed out), and to some extent the condition of the track (as Jim said). OK, and to a degree, my over enthusiasm at being on the right line and getting faster... (Message edited by Pariah on September 02, 2008) | ||
| Fresnobuell |
I agree the owners manual is closer to the right settings...that's about where I am now. My main observation is that the service manual is substantially different, recommending much stiffer settings. Just for example, for the forks the 170 to 190 pound recommendation for the damping settings (compression and rebound) in the SM matches the recommended setting of a 250-270 pound rider in the OM. And the rebound on the rear is completely in different ballparks between the SM and OM. Something is off, way off. (Message edited by fresnobuell on September 03, 2008) | ||
| Pariah |
Yeah, although the Service Manual was out later, perhaps they rushed things a bit... maybe there'll be a revised edition... Court would know. Court knows everything. | ||
| Fresnobuell |
It's worth a question to Buell...I mean one is wrong and one is right. There is no way they can both be correct, there is such a discrepancy. My feeling is the Service manual is the wrong one. I pity the fool who gets their bike setup per the SM by the dealer...he is in for one harsh ride for sure. | ||
| Chadhargis |
I run the Corsa III on the track and I've never had any grip problems with them. I typically start with 32F/32R cold, then I put my warmers on. After about 45 minutes or so, I check the pressure to make sure it hasn't jumped up over 35 or so. I keep a watch on pressures throughout the day. I try to keep hot pressure under 35psi. The tires will typically heat unevenly front to rear. Typically my rear gets hotter than my front, I guess from doing more acceleration than hard braking. I've done as many as 5 track days on a set of Corsa III's. That was pushing it, as toward the end of the 5th track day, I was getting a little spin out of the rear tire. And this is on a 600, so God help you on a liter plus twin. I think I'll be retiring my III's after 4 track days. Using warmers helps them last longer as I don't heat cycle them all day. But eventually, they give up the ghost before the tread is gone, so don't use the tread depth as a indicator of tire health. After I retire them, they go on my Ulysses. Well, at least the front one does, the rear is usually fairly well shagged. | ||
| Pariah |
That's interesting that you use warmers... I've heard that warmers on street tires can affect them a bit negatively, but then again, the Corsa IIIs aren't typical street treads. I like the idea of avoiding heat cycling... maybe keep the warmers on loosely? | ||
| Patrickmitchell |
I run DC IIIs on my track bike... pressure hot should be 30-31 front and 29-30 rear. The tire techs for NESBA and TPM agree with the above mentioned numbers. The settings you mentioned in your first post are fine for the street, but WAY too high for the track. I occasionally run super corsa DOT race tires and their pressures are even lower. If you are still spinning up the tire, lower the pressures even more. | ||
| Black_snowman |
Don't forget that ideal tire pressure is effected by suspension as well. Buells, the 1125R included, have less unsprung weight and react faster to surface changes and the suspension is designed to take this into consideration. If the tires are too soft they won't transmit surface changes to the suspension as quickly as it's designed for and won't react correctly reducing traction. So pressures on one bike, or a bike with suspension mods, will necessarily vary with the same tire in the same conditions, and the same weight of bike and rider. Just to complicate matters. If it were simple, there would be a handy little chart. When I did a riding course with VRS Dave thought my front wasn't stiff enough for the track but thought it matched the rear nicely once we tweaked it. My bike is set up from a 220 lbs rider by the owners manual (at least, that's what I was told). We added a whole turn of compression and half of rebound to the front if I remember correctly. That makes it quite harsh on the street but gives good feedback on the track. He also pointed out that the 1st thing to get right was spring rate and fork oil weight. Which means changing out springs and oil. He said before you have those matched to your weight you're just patching holes trying to fix those issue with adjustments and you won't be able to truly maximize your traction. I only have 1 track day under my belt, so take it for what it's worth. | ||
| Slaughter |
One really critical thing to TRY if possible - do a track day at a location where the tire vendor is setup. Have them look at the tires just as you come off the track - check pressures and get their recommendations on pressures based on how the tires are wearing and the pressures taken while HOT. They can also help you with minor suspension tweaks too. The tire vendors are an AWESOME resource. Can't get that kind of help from the online houses that sell discount tires (often for not much cheaper than you can get trackside too) | ||
| Pariah |
Great ideas, thanks! Sliding was exhilarating, but best not to repeat. I'm looking at some serious cash for a new helmet, gear repair and motorcycle parts. Scary thing is that I didn't feel like I was pushing that hard... kinda freaks me out. | ||
| Patrickmitchell |
Others have mentioned this: Suspension set up is very important. With out the proper sag and at least base line dampening and rebound settings, tire pressures will only have minimal effect. Make sure you set the sag with all of your gear on. I suspect that Buell's recommended pre-load and other setting will be in the ball park (they were almost spot in for my XB, assuming your honest with yourself about your weight...). You can learn more in one day on the track than you can with years on the street. Have fun! | ||
| Spectrum |
Pariah - Sounds like from your original post you know all this already, but thought is was worth repeating. Probably the most important thing I learned in the Keith Code school is that almost all "get offs" are caused by rider error. In other words improper rider input to the bike at the wrong time. We tend to blame the tires or suspension instead of our selves. Setup is only good for fine tuning and making you faster. Keith repeats this over and over to drill it in "Crashes are almost always all rider". The improper input usually falls into one of 2 categories. That being body position or brake/throttle control. Brake/throttle control - Once you get into the turn (leaning the bike) you should be rolling on the throttle. Chopping the throttle or braking will cause too much weight to shift to the front tire resulting in a low side. Our natural instinct is when something goes wrong in a turn to let off the throttle or hit the brake. Keith had us do drills to re-wire the brain. Bottom line is our instinctive reaction will cause us to crash. When in doubt, roll on more throttle! Body position can effect so many aspects of the bikes handling (center of gravity, weight distribution, suspension compliance, etc). I kept feeling like I was going to loose the front end in a turn. The instructors pointed out I was gripping too tight and even pushing down on the handle bars. This was putting too much weight on the front end as well. They showed me in photographs that my elbows were up. Told me if your elbows are up your shifting weight to the front wheel, if your elbows are down, all your weight is on the pegs or seat which is keeping the weight properly distributed. I still need lots of practice/improvement, but I improved more in 2 days on the track than I did in riding 2 years on the street. | ||
| Pariah |
Bryan, The level of instruction that you are describing doesn't seem available to me, locally. And, I agree, my technique needs LOTS more work. Where did you attend Code's school? Did you bring your own bike? Did you do the 2-day Camp? Closest one to me would be Barber... given my experience, though, sounds like it's worth the trip from Texas... hmmm... Cheers, Takis | ||
| Jdugger |
>Where did you attend Code's school? Did you bring your own bike? Did you do the 2-day Camp? > Closest one to me would be Barber... given my experience, though, sounds like it's worth the trip from Texas... hmmm... Pariah, I've been to a code school, and it's very much worth it. The school is very, very expensive, but also very much worth it. The two-day camps will allow you to pretty much fly in with nothing and they provide everything you need. It's a good option. Barber is an amazing track, but it has funny rules. No one on before 9, mandatory lunch break, and no one on after 5. So, you can really miss out on track time if a little sprinkle comes through. Call the guys at the code school and ask THEM where to go. I'll bet they tell you willow springs, but there are other good options. I'll be going back to code for level 3 and 4 as soon as I can afford it. | ||
| Spectrum |
I did the Keith Code school Level 1 at VIR. I used my own bike and the 1 day course was about $500. I was on the track 2 consecutive days as I did the Buell Inside Pass at VIR on the South Course and the Keith Code school the next day on the North Course. I highly recommend Keith's school and will be going back for Level 2 next time they are at VIR. | ||
| Patrickmitchell |
+1 for the Code school. I've taken level 1 (at Pocono) and 2 (at NJMP). Pocono was fine for a school, but I won't ride track days there any more. NJMP is about as good as a track gets. THE SCHOOL IS WORTH THE $$$! If you are serious about improving your riding, or have become a track day addict, these will radically enhance your skills. Read the Twist of the Wrist books before you go. Keith's teaching is unique and it helps, but is not required, to understand his terms before you show up. There is no question that I got more out of the track time by reading in advance. PM me if you want some more details. (Message edited by PatrickMitchell on September 04, 2008) | ||
| Jdugger |
Pariah, One final thought: Since you are in Texas you can look up the schedule for Lone Star Track Days (LSTD.org). They run track days at various tracks around Texas. Sign up for Novice with instruction. Both Ronnie and Tom are excellent on and off track instructors. There are others, but I know those guys. It's not Keith Code, but then again, it's a quarter (or less) of the price and it's also a very good value. I found the classroom material to be very good for the money (again, not Code, but at the price point LSTD charges, it's *fantastic*), and I found the on-track instruction to be excellent by any measure. I did a track day with them at Cresson last month, and learned two techniques around braking which have been very helpful on the street I didn't know before... even after a 2-day camp with Code. (Of course, braking isn't really focused on in code's levels 1 and 2...) | ||
| Clarkjw |
These tires are so good you don't even need air! Seriously, ambient temp, your weight and suspension setup will have alot to do with how your tires perform. Pirelli makes wonderful rubber and you should be fine if you follow their reccomendations. | ||
| Cutty72 |
Ran mine 29/29 cold about 70-75 ambient temp came out about 34/35 hot off the track, and they stuck. | ||
| Josh_ |
I run 32/33 on the track and stock 190lb rider setting, except the rear rebound at 1.5 turns. I talked to a suspension guy at Hallet who was decribing how to tell if your compression or rebound were dialed in by how the tire wore from the edge to the center. He also said modern suspensions have pretty much no rebound/compression adjustments beyond 2 turns out. (and I let him set my rear rebound to 1 turn out and about wadded on my next session but that's another story) I would not recommend the Code 2-day camp, the only thing you get there you don't get from two 1-day camps is riding the bike with the camera on it (the one that films your body position). Feedback I've gotten is you don't really get any more track time. I would certainly prefer to ride my own bike at a class. A 1125cc Buell rides a little different than a 636cc Kawi. |
