jps600rr

Following the guidance in TOWII ie the ideal weight distribution for the motorcycle during cornering. I assume the best body position is as far forward on the bike as possible, thus enabling a higher level of throttle, to ensure the best weight distribution, which is approximately 30-40 front 60- 70 back. So to me the position of the body forward or back determines the relationship between cornering speed and lean angle. James.

On the question of braking, on my CBR600RR I have found the brakes very easy to modulate, it takes a full hard pull to make the brakes bite hard, small changes in lever pressure only make very small changes in braking until you get to the end of the lever travel. I found on my F4i that the brakes bit harder sooner, and were much more difficult to modulate. I have found from my riding on the street that if I want to slow down when leaned over a light touch on the brakes to start with, and then stand the bike up, as I comes up you brake harder, you have to be progressive about it. Standing the bike up and then braking means you have covered more distance in a given time period. I think what happens on the street is that some peole just give up on the front brake, and stand it up, and slam on the rear, which is very diffcult to modulate. And off the road we go. Trail braking under race conditions cleary requires a great touch, but I think for the street rider trail braking has advantages. In may ways it is no different from braking hard in a straight line if you want to stop quickly you need to know how to modulate the brakes, and with a little practise you can get very good. I agree that on the track if you set your entry speed reasonably well you should not have to touch the brakes at all, and you can certainly concentrate on the line, and momentum. I have the DVD, and I still think that the CSS is great. James.

Trailing the brake: OK, just going to put out one thing here, when the brake is being trailed, does the bike want to hold it's line or run wide? Will there be more or less effort to turn it? CF I understand exactly what your point is, but one can apply the necessary force to the bike to turn it, but it does take effort, weight lifting has its advantages some times. In addition to this letting off the brakes, and waiting a short time for the bike to settle means you are gliding. Also a fine touch with the brakes is required, but I think that is a necessary skill to learn. Having the ability to trail brake to some degree is a big advantage compared to those who have never tried it. many have mastered the throttle. But the brake. is another story. If you have come in too hot staying on the brakes can stop you from running wide. Also the harder you can brake the deeper you can go into the corner before you turn, because eliminating the glide distance is a significant advantage. i has seen photos of Doug chandler hard on the brakes, while going through a corner.

Trailing the brake: OK, just going to put out one thing here, when the brake is being trailed, does the bike want to hold it's line or run wide? Will there be more or less effort to turn it? CF I understand exactly what your point is, but one can apply the necessary force to the bike to turn it, but it does take effort, weight lifting has its advantages some times.

The inherent problem with that logic is that when the front end is compressed beyond compliance, you're far more likely to lose traction (and fall down). Turn in is as fast as the rider makes it. Yes, the bike's geometry has a bit to do with it, and having the front compressed and rear extended creates an instability which favors 'twitchiness' which makes the bike want to 'fall' into a turn. However, this same result can be had with a concise input to the bars. Ok just to clarify I break very, very hard, gently let out the brake, and turn with some pressure on the brakes, but the front end is not fully compressed, and I do contersteer the bike wants to turn very fast, which is good.I think this is the fun part about riding, nothing like the feeling of hard braking, it is also a good work out to. Strictly from a turn-in perspective, no, being hard on the brakes will not improve the speed. It's all about rider input. Trail braking can work, and can be effective. However, the amount of concentration rises significantly and the majority of people I see trail-braking can't cope with it and either end up overbraking or falling down.

It seems to me that we have a relationship between how hard we brake,downshift,slowdown, and the turn in point should the bike be sliding slightly just before turn in, the harder we are on the brakes the faster it should turn in, but if we release the brake, and then turn does that not lead to a slower turn in? To me this transition seems to be the most critical of all the issues in maintaining high corner speed. Is trail braking a consequence of a fast turn in? James.

James--ALWAYS brake first. Scrub some speed off, then you don't have to rev the motor as high to match the rpms. Guys that can do this well don't even have to use the clutch on the downshift. Downshifting first is very hard on the bike--chain, clutch, engine. Brake pads are cheap, and meant to slow the bike, so don't use the engine as a brake. Make sense? CF I understand what you are saying, I do brake first myself but I may be too close to the red line after the downshift. I think the question is how close to the red line/which gear do you want to be in through the corner, depends on how fast you can come out of the corner. The 1000 seems to be much more flexible compared to the 600. James.

I am downshifing at too higher speed, some people say downshift first, but if your speed is too high, then you need to brake first and then downshift. James.

Thanks, It is most likley a rear, and front skid, downshifting, and applying front brake at the same time. It only happens for a very short space of time, just before I turn in. You tend to notice the front more in this situation. Better come to school before I get too carried away. Thanks. James.

While hard on the brakes? maybe, but still highly unlikely. A front tire skid on a race tire that is up to temp is VERY hard to do. About the only way you can do it is to bottom the suspension and then 'pogo' the front end where it hops off the ground a bit. Otherwise, you're more likely to go over the bars... now I'm not outright calling you a 'liar', but I really think that if you had some video you would see something different from a front end slide/skid... Not I can clearly hear the skid, no brakes

I have noticed when making an aggressive down shift from med RPM to high RPM the front tire skids for a split second, the back tire is fine, very stable but the front seems out of control for as split second. Then it regains traction very quickly, and the bike is stable, this happens just before I start to make the bike lean. James.

Thanks Cobie for your input, I do blip the throttle but at low RPM the clutch makes it smooth, I will try it without the clutch and see what happens. Are you saying that it is possble to elimate most of the clutch useage apart from stopping? Good input on the throttle, I take the free play out of the cable, and then roll on the throttle smoothly when I feel the tension, but an adjustment here may help. But that first crack open of the throttle is a very very small movement indeed on the CBR. It's seems like a worth while investment to use your bikes at your school, and find out exactly how the bike needs to be setup. Sinice I live in AZ that may be the best way to go anyway. I need to check the school schedule to come work with you guy's. Thanks. James.

I agree that not using the clutch at all is an advantage on the track, and this works well when you can keep the bike in the high RPM's.certainly a 600 can be kept at very high RPM's. Riding like that requires space, and a known good surface. Your comments are certainly directed to track riding. Also the slipper clutch is standard on most bikes today, so clutch slippage is built in. Part of my observations are that the sports bikes are realy designed for the track. Thanks. James.

I have found on my CBR600RR that the off to on throttle reponse can be a bit abrupt, instead of going completely off the throttle, sliping the clutch a bit when necessary seems to smooth out the bike, it is usually only ncessary in very low speed turns. Also holding the throttle open, and applying the brake gently keeps the bike very smooth. It seems to be a common complaint from bike testers that the CBR's have an abrupt off to on throttle response, even at higher RPM's, but I have not seen an issue at the higher RPM's myself. I agree that using the clutch at higher speeds most of the time is not good, when I down shift too early, or if I don't like to the look of the road surface, when shifting at higher RPM. I will let the clutch out in a controlled slow manner. The track, and the street are different enviroments, and require a slightly different approach. On the track using the clutch will cost you lap time, on the street using the clutch to modulate rear wheel power at the right time will keep you up right. Thanks. James.

I have a question about the use of the clutch in controlling the back wheel, if holding the throttle steady helps the bike correct itself in a coner slide what effect does engaging the clutch have, if the clutch is used in its friction zone could we not regulate the power to the back wheel and control the slide with fine control? Also what would be the effects on the bike dynamics, and ground clearance? I am thinking of a rear slide not a front wheel slide. To add to this I was reading an artical the other day that said if you get into a corner too hot, the throttle, or putting the bike in nuteral would work. (I think they mean engage the clutch.) but do not chop the throttle. Sinice I ride on the street I have not created a real slide to test this theory of clutch control. Any input would be apreciated. Thanks. James.