isolastic vs solid chassis behavior??

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I've a firmed opinion now but still wondering what others experience in maxing out on various type turns an isolastic vs a rigid chassis? I only know I almost crash on moderns trying to approach the secure G's I get on a tamed clam Commando.
Here's the lit kindling. Hard to compare power character but I'd suspect flywheel weight might delay the snap if otherwise similar. My first reflex learned on my past Combat accident combo, was grip hard and plant butt before throttle snaps or it'd run out from under till 3rd reached. I can feel Cdo frame twist but unwinds in one damped motion no rebound. I sense this twist helps compensate for tire traction and direction conflicts, A Lot. Its tackling the tightest chicanes that fascinate and please me the most. Herb who please, hobot

Doug MacRae
A solid mount frame like a Seeley has little or no advantage over my isolastic Norton because of some of the handling mods Herb has done. The vibration from the solid mounts can put your hands to sleep too. I have been considering doing a post showing all the mods with pictures, I will get to it one of these days.
If you are going ultra modern, mono-shock with mags, modern forks and brakes etc., that is a whole other ball of wax


Chris
Hi Doug
I too would be interested. I ride a Seeley but because of a gearbox problem ended up riding a Norvil proddie racer. Long story I purchased it because the engine is the same spec as mine & it has a Quaife 4 Speed box etc. I am building a Norvil for a friend so two birds one stone so to speak. He gets a roadbike I get quality spares.
Anyway the engine felt flat compared to mine, however it was fast. Is this lack of urgency just the isolastics doing their job? I noticed coming out of Barn at Cadwell (an off camber down hill right hander) that the bike moved out as if it was going to drift wide & as the power was put on it came back on line. Again just the isolastics? On fast corners with a steady throttle it went where I wanted it to go but did not feel as precise as the Seeley. Weight? Not unsettling just more effort required & more movement.The main reason I didn't enjoy the ride is a combination of the 4 speed & the silly chicanes that have been put into a few circuits here in England. 2nd gear would not pick up & pull quick enough exiting the corner but 1st was too low & I had the back end wiggling under braking. ( standard rear hub, Maney belt drive. I don't know what the front pulley Clutch basket & sprocket are yet) At that speed the front end just dropped into the corner! I found myself jumping the kerb. Not really concerned as the road bike wont be used like that but I would like your thoughts.
all the best Chris
 
A tamed clam Commando?!?

Hobot, what the heck you ridin' man? (I almost said "smokin'....")
 
ugh, a calmed Commando, not a smelly ole clam. But tame as a sticky ole slug!
Past late great Ms Peel with spiced up Combat engine but with rear 'rump' rod and its two helpers, for out of this world neutral handling and uncanny disappearing sense to pilot of a ponderous huge inertial mass that flicks no effort "Ricochet Rabbits". R-R's are my nick name for phase 4 turns, two phases funner than my meger skill allows me on regular Commandos or jazzed up modern sports handlers.

I seek to learn how others experience various bike limits that annoy pilots to press onward. I'm still chewing on Chris's description to digest between hard and soft.
Also Doug's racing proof isolastics don't delay him any. May tie into martial arts, like Karate vs Aikido. Or sword vs stick. Newton vs Einstein. Digital vs Analog. CD vs Vinyl. Man vs Robot. Oh yes, its that good for me. Maybe new physics revealed.
 
Not sure on this one, but would the fact that the isolastic system fitted to Commando's not make accurate alignment between the front and rear wheels while the bike is being ridden very difficult? When I used to work on Norton back in the day when they were current I was never able to figure this out completely, or why stiction in the rear shocks never seemed to present any major problems?
 
Alrighty Carbonfilament! Touchy subject on how cockeyed Norton sold em or people bent them and how much it matters. Here's what little i know so far. The hand full of 750's I've checked all had rear rim built off centered to the Rh ~3/8". So is the power unit about 3/8", I'm told to get some tire/chain clearance. I've fixed flats on rear away from home a few times, just getting it eye ball/finger space aligned and could not detect any effect hands off or attacking stuff.

The most impressive test of the innate stability, about no matter how misaligned and/or out of line tires are, was shock to see my buddy whiz past me over 100 mph after dragging his ass for 1200 miles hanging back over a mile or out of sight routinely, to point me over excited as hell, breaking my spell of standing on pegs in July heat, finger tips only on bars to keep throttle to push steady 90 mph over very broken up and humped tar seams in concrete slab straight highway, because he saw lots of smoke coming from Peel so I turned back to see dense cloud of white smoke a mile long obscuring cars, because the rough stuff finally fractured dummy axle and relieved clamp force holding R axle on adjuster and tire was tipped sideways full R so fender slicing a groove Plus also twisted in swingarm to rub a shiny spot thru the powder coat. I did not feel a thing and it was a windy day with semi's blasts going by. I was going 25 mph faster than traffic so didn't look in mirror very often then.

A hose clamp helped hold tire off fender and rode another 40 miles like nothing wrong at all EXCEPT that on first take off till 12ish mph it bucked like a flat tire flopping, then settled out undetectable in sane get to a motel and truck rental riding. Also there was a bit of a flip/flop just before foot down stopped.

So to stay on point how would a cockeyed rear wheel behave in a un-tamed Commando, a Seeley solid or an elite rigid modern?? Maybe someone can tell us as I only know what they do on blow outs not wheel misaligned badly. You don't feel a thing until slowing way up or leaning to turn, then wooowwee!

Axles break too often, worth fitting a safety tie on bikes w/o eye bolt adjusters.
 
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