Quote:
Originally Posted by whatismouse
ive riden my ninja 250 for almost 1000 miles. sometimes im bored, and i think too much. here is the result:
1. when I let my hands off the bars between 30-50mph, the front wheel will wobble from side to side, why is this? Does this happen on all bikes? How do you deal with this phenomenon while stunting, with no access to handle bars?
|
My Ninjette has a front-end wobble around 40-44 MPH (indicated, so about 35-38 MPH actual). It was a lot worse before I replaced the shot OEM front tire and aligned the rear wheel; I'd suggest that you make sure to check your front wheel tire condition and pressure, along with the rear wheel alignment, before worrying too much about it. Apparently it is somewhat normal, though; you can find a lot more information over at
Ninja 250 Riders Club :: Profiles.
Quote:
Originally Posted by whatismouse
3. how do you tell when you are approaching the limit of traction? Once while leaned over I ran over some gravel and suddenly the front end felt loose, like I was no longer connected to the ground. I think the front tire might have skidded a fraction of an inch, and that was what I was feeling. I basically did nothing and didn’t need to. Is that the feeling I need to watch for? I keep pushing the bike little by little and I’m sure that eventually ill find the limit. I just don’t want to surpass the limit at the same time. I need to learn what type of bike feedback I need to be interpreting.
|
What tires are you running? The OEM Ninjette tires give lousy (read: virtually nonexistent) feedback compared to good sport-touring tires. Again, see more info at ninja250.org; I've noticed much better performance since I switched to the Sport Demons.
Quote:
Originally Posted by whatismouse
5. if we are to assume that both front brake and rear brake can be operated from 0(none)-100(full): then while in a turn, if the maximum braking that the front tire can withstand is x, then is the maximum braking the rear tire can withstand also x? let us assume that it is not x, and that it is y. in another scenario, if the front brake is being utilized by x amount, is the maximum braking that the rear tire can withstand still y, or has it now changed due to some change in braking dynamic when both front and rear brake are being used?
|
As you brake, weight transitions forward. As it does so, you have less friction to use on the rear wheel (friction, if you were paying attention in physics class, is equal to the normal force--or downward weight--times the coefficient of friction), and therefore less braking ability. Or, if you have to ask, you should probably stay off the back brake while cornering on pavement at speeds higher than 5 MPH.
Quote:
Originally Posted by whatismouse
6. I watched a video online which demonstrated body posture during a turn. It mentioned to move half a butt cheek off the seat, towards the inside of the corner. That seems pretty conservative to me, if it is possible to move even further to the inside, isn’t that even better? At what point does hanging way off the bike to the inside become more of a hindrance than a help? Im talking about on a racetrack, not on the street.
|
Ask the instructors at the track day you're attending. They can actually see you ride and provide better feedback than we can.
Quote:
Originally Posted by whatismouse
7. im an idiot.
|
Yes, we noticed.
Quote:
Originally Posted by whatismouse
I wear hiking boots, jeans, t-shirt, and a motocross helmet when I ride. If I were to invest in one piece of protection, what should it be?
|
Common sense and a little thought about consequences would be a good start, because it will make you realize that you really need a full set of gear for the kind of riding you're talking about, not just one piece.
Quote:
Originally Posted by whatismouse
8. what safety gear is required to do a track day at a typical track?
|
Already answered, but over-the-cuff gauntlet gloves, 1-piece leather or zip-together (full circumference zipper, not 8") leather suit. Some places will also allow high-end ballistic suits (e.g an Aerostitch), I don't know if all will. Good gloves, real boots, and an undamaged, full-face helmet w/proper regulatory endorsements will also be necessary.
All of the above can be had for not a lot of money if you shop lightly used and clearance stuff. I own three leather jackets, none of which was more than $170 shipped, for example.
Quote:
Originally Posted by whatismouse
9. if the speedo is off by 10%, and the fastest my ninja seems to go is 100, then is the top speed of my ninja only 90mph? is something wrong or slightly off if the bike only goes that fast?
|
With the OEM gearing, I..er...someone I know got mine..err...his...over 100 indicated and felt that, with a long-enough straightaway and no cross winds, animals, or pavement variations, I...errr...he probably could have hit 110 or 115 indicated. The speedo on my Ninjette is apparently off by more at higher speeds than at normal speeds, though; GPS-confirmed top speed at this point is 88 and change.
Quote:
Originally Posted by whatismouse
10. when braking in a straight line, you have 4 options, front brake, rear brake, engine braking, wind restistance. But does engine braking affects the rear wheel in the same way that rear brake does? In which case, since the rear brake is more than sufficient to surpass the braking ability of the rear tire, is engine braking not a factor? Is it possibly advantageous to pull in the clutch, so that you will know the limits of rear brake, rather than be applying rear brake in addition to engine braking (which will vary in significance depending on rpm’s), and make it harder to judge how much rear brake can be applied?
|
There are advantages and disadvantages to both clutch-in and rev-matching as you downshift. You are correct in that downshifting without sufficient rev-matching can lock the rear wheel (common cause: going down from 4th to 2nd quickly when you were actually in 3rd, not 4th).
Quote:
Originally Posted by whatismouse
|
That is a nice-looking bike. I think I may have to go either flat or gloss black with no markings this winter (assuming I get around to repairing the fairing as I plan to).