Steering

[stoinkythepig]

Originally posted by legalspeed

And that leads me to a question I am now asking myself: Self? Just because I do up a fancy web site, does that make my hairbrained opinion a solid fact?
Want an example? How about the guy that holds up two pistons and says: "This one is from a friends bike, he followed the manuf. break in guidelines (piston is destroyed). See the other one, this is one from my bike(piston looks brand new), I rode it hard from the beginning." Yeah, right. Now how the hell is that a qualified scientific experiment? What was the ambient temp? Ambient humidity? What rpms were attained and for how long? Where is your control group? Was the same oil used in both? Was oil even used in both? What is your friends name? As you ask these pertinent questions, you begin to realize there are no numbers, or charts, or anything of substance to back their claims. that is when it becomes obvious they are only based in opinion.
A real benifit: Kevin Cameron's Sportbike Performance Handbook. This is filled with numbers, charts, hard facts, and a friggin bibliography so you can question the sources on what he has claimed. Great book BTW.

Kevin Cameron is my hero. First thing I read in every new issue of Cycle World is Mr. Cameron's page.

I agree with you about MototuneUSA's web site. That said, break in recommendations from manufacturers leave a lot to be desired. For instance: Kawasaki recommends the same procedure for a Ninja 250, a Concours and a ZX9R: "Keep it under 4000 RPM for the first 500 miles" If you really did that to a Ninja 250, you'd bog the crap out of it, I know, I tried for a short time. I know bogging is not good for an engine. The reality is: when Kawasaki completes a bike, they fill it with used motor oil, start it and while cold, run it to redline in every gear on a chassis dyno. They then drain the oil into a big tank for use in the next bike and ship the bike to the dealer. I suspect the used oil is pumped from somewhere other than the bottom of the tank. I really doubt after that sort of treatment, exceeding an obviously arbitrary RPM is going make a big difference during break in. I personally think the best way to break in an engine is to drive it gently while cold and at constantly varying loads and RPMs (while never bogging it down) when warm. Lots of hot/cold cycles are probably good too.

I know BMW does the same "redline in all gears on a chassis dyno" thing to their cars when they finish them too. Must be a reason...

[legalspeed]

Hi Stoink',
I remember that 250 scenario coming up, lovecat's machine I think, good call.

#2, I ride a Suzuki.

I didn't know that Kevin has a column, nor did I know that Kwaks and beemers run em in. I'll have to look into that.

Was that Mototuneusa I was disrespecting? All I remember is some dopey lookin' character holding a couple of pistons saying "See, my friend followed man. recommended break in. Shame on him for destroying his engine."

thanks for your reply, I think you have a world of knowledge and I like the way you present it.

[stoinkythepig]

It was indeed MototuneUSA and that photo of the guy with two pistons bothered me too. The good piston had no carbon at all on the sides, even above the top ring. Sorry, but you cannot run an engine for any length of time and have no visible combustion residue. Total BS picture but some of his ideas make sense to me, just wish he'd lay off the bogus photos and weird philosophy and just stick to the facts.

I especially like his ideas on making intake ports smaller in diameter for a flatter, more useable torque curve on 600cc race engines with HP limits. Makes perfect sense to me. I'm wondering how long it will take for variable length intake runners (like BMW has on some of their car engines) to make it to Honda bikes (I just know it'll be Honda, if anyone does it). I suspect the torque boost from that would make a 600 feel like a 750 or bigger.

Kevin Cameron's articlas can be seen at cycle world's web site.

[Polonius]

Thanks People


I appreciate your input. With your input, I believe that I now have a better understand about the dynamics of steering. Your personal experiences have confirmed some of my understandings and suspicions.

For an extremely slow steer, the front wheel has to be pointed in the direction of the steer. This is not a counter steer situation.


Under 30 or so miles, a lean into a corner by pushing down on the side of the bar into the direction of the steer will work. Upon discovery of a tighter curve, a more agressive push down on the bar is required. This is still not really a counter steer. This I suppose could be described as a direct pressure steer. There may, however, be some small unperceptive amount of counter steer. The head should remain verticle to keep the horizon horizontal and able to view as far as possible into the curve to the exit.

At over 30 or so, a counter steer, a light push forward right to go right and left to go left, because of gyroscopic and gravitational forces, will force the bike to lay into the curve. More agression can be applied by sliding the butt over the seat to the curve side and if necessary to tighten the curve, a direct push down can be applied.

Rozumisz?

I believe this is what you were all driving toward.

Any further comments would be welcome.

[stoinkythepig]

What's this have to do with pistons?

[Kham]

Originally posted by stoinkythepig
What's this have to do with pistons?

exactly! chemistry vs. physics.

[Polonius]

The question is???


WTF are pistons doing in my steering post???

[Half Squid]

Pistons do belong here but in this order...ton O' pis

If there is a ton of piss in a corner that your countersteering through you'll end up on the ground!