Quarter Mile ETs, forum members

[Carbonfibre]

If Norton power trains are so flexible, then how come they handle so well in a Seeley MK3 chassis with no down tubes? Like I've said (a couple of times) I know the theory but in practical terms non unit construction beats the rest.

If you have 2 entirely separate assembly's, which are joined together with thin and relatively flexible sheet steel plates, its not difficult to see this arrangement is nowhere near as rigid as a unit construction motor, without the sheet steel engine plates.

 

[Hobot]

Don't be so rigid in your thinking, reflect on the attempts to build in some sideways give in swing arms and forks, because they have begun to get fast enough in turns to notice the tires are going separate ways and feeds back into chassis to then tweeter out the tires, so they try to allow some twist/bend/flex that is out of line with normal hi tech suspensions. Pashaw that's because they still think and depend on front tire as steering bike instead merely a rudder assist for rear ruling the roost. I think they got it right to centralize mass and make the ends stiff but they they are shooting selves in feet not to allow the flex to occur in the middle too instead of at the end of a spring broad. We are only talking a few silly mm's here not the extreme wiggle wobbles an un-tamed C'do gets or the super high reasonace splashes the twangy angry looking insects get hit with.

Everyone one on their super duper life raft tyred digital brained rides depend on front tire traction to UGH, slow up for turns and YIKES! to turn sharper and sharper on less and less traction. When there's power and grip enough to lift front accelerating, guess what happens doing that into and out of apexes when not lain over on an obsolete magic carpet unicycle that essentially can't slide only chirp, skip and pivot ... which are just spike launch points off more traction to get on out of there into new levels of energy handling ballistically.

BTW when show room bikes are just strapped down they cut like seconds off their ET's.

 

[Carbonfibre]

How exactly do you beat Jap and Italian sports bikes in the turns, when you are running bald tyres, and have no cornering clearance? Maybe you need to provide your secrets relating to this to Ducati to help Rossi out a bit?

 

[Hobot]

Now you've put on your thinking cap,cool. Ordinary common rear sets plus 2" lifted in front allowed ~60' clearance. You nailed one of Peel's advantages, ability to lean more than 60's and still have more stick on dual purpose narrow cleated tires than my Suzuki's non DOT almost slick tires, so soft cold pebbles didn't get scrapped off in loud fender noises, till I returned off tarmac then so soft it'd release stones after locking them in place for THE Gravel Traction. These dual purpose tires were a failed lesion to cross THE Gravel on as its identical behavior to Dry Tarmac, that is no way to dig into surface so cleats just subtract surface area to grip but at least they didn't deform on side ways pavement rushes. Even on such hard compound tractor like tires Peel could run circles around my SV and MX bike I rode on THE Gravel. I'd come across the teens on ATV Blasters and out race them too but too scary with no reserves to dodge anything so just short drags a few times plus some wider sweepers, then I'd give up d/t groin fear spikes in the 60 mph leaning zone.

Here's Peel with Drouin mock up mounted.

This lift required a crutch under the side stand, ugh. Next Ms Peel wears 15" shocks to lift rear to match front. Here she is in '04 weighing about 360 with a few gallons in IS tank and luggage rack. Back thing next to RH mirror is dual EGT/CHT meter. Btw each factory exhaust side weights about 9 lb, 3 in pipe and 6 for peashooter not counting the mount plates. This is prior to the rear sets installed for more leanness in mass and angles.

All forks extend/expand as soon as a bike is leaned over, whether under power or not, only stupid trail braking compresses them when leaned. At some point of phase 2 handling, powering into leans with front pointing outward from the turn radius the front would try to pull bike into low side and wash right out, ugh. That's when I'd have to suddenly transition to phase 3 straight steering to stay on power and turn sharper yet. But Peel could easy handle staying just below phase 3 and slide wide and lazy crossed up like flat trackers or the cool hi speed upright drifts famous road racers do like ole Rossie. That don't cut it on narrow wagon trails on plateau faces or THE Gravel, so only do that for relaxed fun when I spin Peel on her CoG axis and hold her mostly sideways crossed up to direction of travel till aligned with new opening then just relax so she pops upright, rear re-grips hooks up sharply to leap ahead on both tires inline again. The uncanny-flabbergasting part is all the other cycles would want to keep falling down as tires slid out, so would have to put a foot out or wipe out so quit that in short order on anything but Ms Peel. So to me on Peel, once a counter steering drift started that was the end of going faster/tighter that way, its the end stage of usefulness of phase 2 counter steering and beginning of phase 3 transition into bicycle circus straight steering hands off stunts. This is also the limited top end orbit moderns can sustain. My shock here was how easy the fatso tires let go at such low G's, totally shocking to have modern bike go skipping out in surprise w/o even reaching Ms Peel's mere get there safe and sound commutes to appointments I make my living from.

My sense now is that wide ass tires have more a horizontal egg shape profile to direction of travel, sort of like paddle cleats on hill climber/sand duners, wonderful for bee line sprints, but as bike leans those paddle edges get more and more in line with the sideways turn force and then just slide along long axis of a squat egg shaped profile. Narrow tires seems to present more of a canoe/ski shape profile to the side forces on edges. Total area of patches are very similar on similar weight bike/rider combo's no matter the tire width.

The above tire disadvantage shows up nailing a modern on edge, it can't hook up enough to lift front only spin out,they must wait and wait till past apex before they can nail in front lifting thrust. Also they are still trying to depend on front tire weight to help hold bike in a lean against tire gyro's but at same time this fork leverage is trying to lift rear out of traction into more low side danger. Shoot in a real chicane them moderns even supermotards are on brake to slow up enough to take less lean they can handle. Motards generally don't have power enough or stable enough to take the stress to spin the rear to get the pivot on CoG to 'back into' a tight turns, they generally stomp rear brake, which does 2 things, one slides rear out and two throws in some hi side force to pop em back up before falling right down.

So to sum up Peel in real mean leans, could get so low I had to keep knee sucked to tank and tip toes on pegs, then could resist the outward fling ups of hi side G's and either drift wider relaxed, ho hum, no effort to keep exact same lean angle and radius turn, as she stayed stable in any lean angle unless I gave more input to spin rear to trip out further of let off for the hi side save. But the crux of the matter is Ms Peel didn't need front to steer a turn after phase 2 low orbital left behind. When straight steer thrown in, or actually thrown on to fork by tire following the turn arc, [think sail boat boom in a tack] she hooked so good she'd lift the front in a sideways wheelie powering out of apexes that seemed to pivot on rear axle axis and drop front down way sharper, then automatic hi side back upright aligned into new open on better grip yet to leap on out of there way faster than entered all set up for the next one usually after snicking next gear to protect engine rpms and keep on accelerating harshly.

Ms Peel was a total Neutral handling bike, that is it took same effort to lean over as to get back up and would stay at what ever lean angle was set, essentially hands off, sliding or flying up, all the same to her sedate manners. If I really tried hard I could get her to slide on tarmac at max leans and then I would have to hold forks enough to stabilize/dampen but not for steering effort to stay on aim. All in the R wrist action so no athletic's involved, a huge advantage on heats that lasted 30-45 min of red lining tranny bush burning in lower gears.

This is literally the killer application zone of fork dampers, they allow a tiny tad more speed on conflicting tire load stability of modern cripples but then prevent the fork action to really follow the road texture when the going gets low and rough OR for pilot to snatch a save in time. They are total taboo to me and when I see them on a cycle my heart drops and look else where for a more capable bike to tease into contests. I have Scott's damper I removed off SV650 in case you think I ain't familiar with the good stuff, pashaw. If your beloved Duckies sport dampers then they are freeway cruisers only to me, though very capable missiles above 45' leans so I must up Peel's power like 3x's to keep up or maybe out sprint to who knows what yet.

Only advantage reason for big fat meats is the heat handling spread across more area. But that opens another can of worms into quantum level indeterminacy of all the random splish-splashing that goes on in un-dampered chassis-power pulses of over rigid moderns resonating on balloons with sluggish sonic hysteria. There is a sonic zone of tire adhesion that ain't melting and ain't abrading, just smearing out of the effective traction edges. I call it hum, growl, squeal and chirp. Moderns can't convey that delicate balance to pilot as so confused with all the other vibrations inter acting. pashaw.

 

[Fullauto]

If Norton power trains are so flexible, then how come they handle so well in a Seeley MK3 chassis with no down tubes? Like I've said (a couple of times) I know the theory but in practical terms non unit construction beats the rest.

If you have 2 entirely separate assembly's, which are joined together with thin and relatively flexible sheet steel plates, its not difficult to see this arrangement is nowhere near as rigid as a unit construction motor, without the sheet steel engine plates.

So anything with unit construction handles better than a Commando?

 

[Hobot]

C'do's are plenty capable to flip onto their tail light so scary to go all out on launches.
Here's discussion by those doing it below 11 sec.

http://www.fireblades.org/forums/drag-r ... nters.html

 

[Matt Spencer]

and relatively flexable . sheesh . Mustve left the bolts loose . Like to see you try and bend them with youre teeth .

Also its evidant Suzuki was the only Jap manufacturor who had any ideas about competant chassis design of their own ,
in that era .

Why , the kawasakis were still doing their renouned wobble at the G.P. Last Sunday . :lol: Yamahas Copy , and Honda
swamps inadequate design in development R & D funds .

 

[Carbonfibre]

If Norton power trains are so flexible, then how come they handle so well in a Seeley MK3 chassis with no down tubes? Like I've said (a couple of times) I know the theory but in practical terms non unit construction beats the rest.

If you have 2 entirely separate assembly's, which are joined together with thin and relatively flexible sheet steel plates, its not difficult to see this arrangement is nowhere near as rigid as a unit construction motor, without the sheet steel engine plates.

So anything with unit construction handles better than a Commando?

Any bike where the power unit contributes little or nothing to the rigidity of the chassis, and which is further compromised by having the rear end of the bike rubber mounted, and able to move independently of the front is never likely to handle that great.

 

[Carbonfibre]

and relatively flexable . sheesh . Mustve left the bolts loose . Like to see you try and bend them with youre teeth .

Also its evidant Suzuki was the only Jap manufacturor who had any ideas about competant chassis design of their own ,
in that era .

Why , the kawasakis were still doing their renouned wobble at the G.P. Last Sunday . :lol: Yamahas Copy , and Honda
swamps inadequate design in development R & D funds .

Reading some of the crap posted here, makes you wonder whether or not any of those posting it have ever ridden a motorcycle at high speed?

 

[Matt Spencer]

They were GREEN & wobbling . They HAD to be Kawasakis ! ? .
The T.V. comentator came across as a raving ignoramis , to me . Throwing in a few tecnical tit bits , hypeing it up
but distracting you from the actual race .treating it like a Horse Race , even .Better with the Sound OFF .
You can figure out whats going on, its obvious half the time he hasnt got a clue .

Not to mention it wasnt mentioned theyd cracked 200 mph once . :? They may well need that much rubber to get the power down , but a few drops of rain and half of them drop it , The worlds best riders , or the worlds best payed ? ?

Have a think , if you were to redesign the Commando , useing a engineers eye , without altering any of the concepts .
Obsolete is drivle in relationship to the layout , or Why are H.D. still selling there large tourers , even if it is to ratbags .

http://www.kitplanes.com/magazine/fixed ... 75-1.phtml
Theres actually a word describeing the existance of character in machines .Cant think of it right now.
But I think it pertains more to , or at least that character is stronger , in ' man ' built rather than automated process built
machineary .
As for the Grand Prix , when the new Honda or whatever it was came out , at one of the European races , around a year ago
Rossi & Stoner were rideing as rough as guts , in 2nd & 3rd . While the bloke on the new contraption was tucked in and rideing clean and smooth . without leaping all over the place , with the bike emulateing it , like the other two .
Each lack of continuity in motion looseing them speed , and there waverings increaseing the distance and adding bends to the track .

It probably the chassis balance , on a Commando where like a Velo or pre War car , the dynamics of the Chassis actually
do a great deal of the work for you , and assist the road holding . IF its set up right , BALANCED , smooth & Gracefull .

Obviously something with twice the grip has an advantage , and if overtyred a Commando , like anything else , would tie
itself up in knots . Its what the early Japanese roadburners were renouned for doing to themselves .

They had to be ridden by an accomplised gung ho wind it on hook it over and steer it with the power merchant , Raceing .

A Ducati Twin , Motoguzzi , or 71 on Triumph twin . :lol: could be said to be the first of the MODERN production Chassis .

 

[johntickle]

I think it's better to look at the facts than to religiously stick to a certain theory and in the mean time "have a go" at our fellow forum members.
In 1973 Peter Williams rode the John Player Norton monocoque to victory in the F750 race on the Isle of Man. He set the second fastest IoM lap time ever during this race (107.27 mph) and shortly after beat the lap record at Silverstone(99.4 mph). He was leading the race from the first lap but ran out of fuel 2 laps before the end of the race.
The 1973 JPN bike used the old pre unit engine/gearbox with the swingarm mounted to the gearbox cradle just like the Commando.

 

[highdesert]

delete

 

[Hobot]

Any bike where the power unit contributes little or nothing to the rigidity of the chassis, and which is further compromised by having the rear end of the bike rubber mounted, and able to move independently of the front is never likely to handle that great.

Not so if ya link the overlapping rubberized frame and power unit together so each tire can aim independently from the other and twist-conform like an articulated road grader but not rebound on its balloon tires. As Matt pointed out every hesitation in full thrust lowers the fast=fun factor But smooth only works well up to phase 2 cornering speeds, then the digital nature of matter and energy appear, just like atom smashers had to add more energy to reach deeper levels of matter and energy. So the best road racers have ease on lean ease on power ease on brakes and now depend on digital brains to interface with pilots which eventually will be replaced by pure robotics, which already know how to reach into phase 4 handling, which non of you even know what I'm talking about, because ya ain't had a cycle that can take drag race harsh power and thrust to change directions like controlled crashing in comfort.

Links only at front and in middle of Commando rubber baby buggies just don't cut it for Peel. Most stable geometry is a triangle for gosh sakes.

Power politics beyond local factory level knocked the British out of the arena back when, not lack of capable engineering.

Here's an SR1000 showing off its handling capacity with best traction tires on low traction surface.pashaw.
[video]http://www.youtube.com/watch?v=QHPOw-Xmm4o&feature=related[/video]

Here's Green brand showing off it phase 3 handling slap down fly up w/o pilot helping. Note it whips back rather sharper than rest of the pack but w/o pilot on throttle is didn't carry through. I'm not crazy when I say a real motorcycle should enjoy controlled crashing dragster turns.
[video]http://www.youtube.com/watch?v=vkYKFZEeEE4&feature=related[/video]

Here's what drag racing turns looks like when the tire grip and chassis can handle it.
[video]http://www.youtube.com/watch?v=ePgDP7hKlWg&feature=related[/video]

 

[Seeley920]

Well, lookee here y'all, the BMW was able to do a burn out on ice......without the front wheel sliding along

And the ice racers don't have trixie rod rump phase 3 phase 2 combat etc etc

 

[cjandme]

My Pops , Used to race speedway back in '47-'48. But said that he wouldn't race on ice, can't say that I blame him, those studded tired look wicked. He said that most tracks that raced at were 1/4 mi. Harringay,Norwich,Yarmouth & Wembly, he said that Westham was 1/2mi. His ride was a J.A.P. 500 with a clutch and a countershaft. I only ever did street racing ('77 Yamaha XS750 triple & '78 CB750F-punched out to 828,balanced & blueprinted, mikuni smoothbore carbs with K&N air filters & a Kerker header) looking back it's a wonder that I didn't kill myself. Cj

 

[Bernhard]

Well, lookee here y'all, the BMW was able to do a burn out on ice......without the front wheel sliding along

And the ice racers don't have trixie rod rump phase 3 phase 2 combat etc etc

errr......are those spikes sticking out of the tyres?

 

[Seeley920]

Well, lookee here y'all, the BMW was able to do a burn out on ice......without the front wheel sliding along

And the ice racers don't have trixie rod rump phase 3 phase 2 combat etc etc

errr......are those spikes sticking out of the tyres?

yep....both sets!!!

 

[Hobot]

Point well taken, current hi tech elite SR1000 all dressed to kill and all they can think or dare do with it is just zippie doodah straight as they could.

Maybe some risk taking riders miss the significance of seeing the green bike instantly self recover from a low side all by itself, even with pilot slung off on the wrong side. Might even think-feel that is a state to avoid as uncontrollable by pilot speed and strength against all the clashing forces.

Wonder how it would feel to actually crave and cultivate ways of getting into that crazy state even funner and more unstable just for the kix of what happens next all by itself - if the cycle can do it predictably time after time, each whiplashing adding invigorating boost to the thrust.

 

[Fullauto]

My Pops , Used to race speedway back in '47-'48. But said that he wouldn't race on ice, can't say that I blame him, those studded tired look wicked. He said that most tracks that raced at were 1/4 mi. Harringay,Norwich,Yarmouth & Wembly, he said that Westham was 1/2mi. His ride was a J.A.P. 500 with a clutch and a countershaft. I only ever did street racing ('77 Yamaha XS750 triple & '78 CB750F-punched out to 828,balanced & blueprinted, mikuni smoothbore carbs with K&N air filters & a Kerker header) looking back it's a wonder that I didn't kill myself. Cj

Yep those two would have had AWESOME handling compared to the rubbery old Commando.

THEY have unit construction.

Anyway, it's 4:45 on saturday morning and I'm just going out to load my rubbery old Norton up and do the equivalent of a John O'Groats to Lands end run for the weekend. Sure hope I don't fall off because of the crappy handling.

 

[Hobot]

Further insights on super rigid vs too flexy. Wonder if there's a Goldilocks compromise?

Frames have not been constructed of carbon fibre previously because it doesn't flex enough, and the dynamics of motorcycles have made good use of the frame flex offered by metallic frame construction. As the metal frames have been stiffened, motorcycle race constructors have found that the natural harmonics of the frame material can influence many factors, often introducing wheel chatter and other destabilising vibrations. The harmonics of the frame is responsible for a lot of the problems race engineers encounter while setting up a bike to perform at its optimum.

As John Keogh, the most knowledgeable journalist on the subject of carbon fibre usage in racing motorcycles wrote, Mamola and Haslam found “the suspension set-up and feedback from the carbon frame so fundamentally different that their normal bike adjustments and suspension settings no longer worked and that the bike raised more questions than it answered.”

Lots more in here.
http://www.gizmag.com/ducati-desmosedic ... ion/11456/