Another solution to the commando wiggle

Ok lynxnsu thanks for being direct with me on this vibe and handling character. Blowing off sports bikes of all nationalities is my main joy in life, but secondary to my craving of the silky smooth disappearing act my Peel delivered. I have spinal injury from birth and many more since so am overly sensitively to vibration, such as the valve train buzz solid mounts transmit even with prefect balance shaft compensation of main engine oscillations. Norton found adding any more rubber area to isolastics made isolation range go up or never quite isolate. This buzz does messes with one's sense of feel and control when pressing limits. It interferes with my sense of patch behavior to tell when its going to let go or stay in grip. My jaw dropped and eyes widened on viewing the triangulated rear linkage and still over my head to quite understand how it works so well for you.

i'm not very brave it seems as only this week have discovered on tarmac with Trixie's Combat un-tammed isolastics, one can induce THE Hinge on let offs rather than just creeping up from below on it. I know very very well about inducing THE Hinge by let offs on THE Gravel. On Peel on dual purpose cleated like tires I could not get her tires to let go just going as fast and furious as moderns on balloon tires, I had to on purpose induce crash like antics by over leaning on spiked throttle to get the rear to slide around to sharpen radius, then discovered the advantages of tripping out faster than human reaction to get the hi side save back up into desired new aim of thrust. Peel forks ride 2" higher so could lean rather more than race bikes and then discovered the ground effects of lift/drop and wind eddies on fork oscillation and predicting tire grip and bike response to pilot. You can not go that fast and low while counter steering or just low sides front right out. Find ya nice forest fire lane road and watch how your Cdo will automatically enter straight steering when traction is not complete, but in best grip of 10-ish percentage slip-age. If you go harsh enough on tarmac so its loose as THE Gravel then it automatically happens but have to let go of bars somewhat to allow them to flip directions in time, but this is also what onset tank slappers in all other cycles I know of but maybe MacRae's swash plate or your bridge work stabilized Cdo. Do lower tire pressure some if pressing things off road. I have yet to find any way to upset Ms Peel and boy howdy have i tried.
Its uncanny flabbergasting fabulous not to feel the motorcycle under you, just the smooth thrusts and G's of turns.

hobot
you are going 100% the other way than me regarding chassis geometrie
i have shortened forks (marzochi) and run on the skiniest tyres possible on my 18 inch wheels , but i removed all that can scrape when leaning over . and yes i am off the old school so no knees hanging out
even on my Dukes i use 750 rear rims (narrower) than std
people using the point and squirt techique for going round (and getting out of) corners are losing a lot of momentum dong so . Disconect your rear brake and go out scratching and you will see what i mean.(you will be scared but once used to it ...)
one gear , no brake works with a std comando 200%

regarding tyre pressure i always need fully inflated tyres for fast raod work , only on track days do i experiment on the Duke , never on the commando . i think the tyres are simply not big enough (strenght of the carcas in relation to fysical size)

meten is weten is an old saying here , meaning only what you measure can be believed , take the bike out on a track day and experiment with it , while checking times , you might be surprised

Why where have I seen this before , .Sorry. But to make a point (GEOMETRY ) NOT who dunnit first ( The JPN F750s ! )



The one I was shown at Pukekohe some years ago , a brief glance , but it was ' up & under ' forward of this lower rear mount .
Front of the tube about obscureing the breather there Id guess . Bolt across the top off the base tubes If I reccall correctly .

The Point Being . Like front suspension geometry , as in ' A ' arms , the locateing points define the load paths . Anti Dive , Anti Squat ,
and suchlike . So , A load Vector diagrame through the three primary connections ( ISOs ) tells us where , Er . . . The Forces are being
transmitted / directed .

Obviously the rear frame area ( around the oil tank ) has a bit of ' triangulation ' / ridgidity / dimensional stability under load .
So if certain cretains had utilised a similar configuration inherantly essential in / to be a COMMANDO , somebody would have been at least partly impressed .

Blather Blather .The Chrysler Chassis manual for A , D , & e bodies explains how to set up the rear angles to hook up under brakeing and acceleration . A SIMILAR
approach wouuld see enhanced traction in a ' rubber band ' chassis . :lol: 8) . ( dont tell the Japs . )Std Mopar ( and other 0 set ups are to provide mediocre
drivers with sufficent feedback to realise theyll spill the groceries , and arnt applicable to 200 mph at talladegga , or chaps of our renowned ilk & refined intrests . :wink:

:? :lol: . SO , some little computer nerd could do all sorts of dynamic represetations , so a more down to earth type could define the best option , which he'd likely manage with a bit of paper and pencil anyway . :lol:

lynxnsu said:

Click to expand...

I like it, but it still needs rod-linked limiting structure; rubber is rubber and allows torsional and lateral movement that we don't really want in a swingarm's rotational foundation.

Not quite so Paul, the extra rubber mount definitely ties the over lapping chassis parts more solidly but then the whole chassis can still twist up and rebound to horrify, on top of the buzz added. The main upset loads seems to come from the rear patch pivoting through rear iso to slap the front iso mounts stilly. If ya take a screw driver and stick in a front frame tab and lever a bit you may be surprised how much how easy the long down tubes twist like torsion springs. A welded cross brace between down tubes helps tame that spring back source. Several schools of thought on the rod link placement and robustness. Some think in line and close to the iso's is way to go, others like me think it better to place links as far away from iso's as practical for better leverage points on frame to resist the twists. Some think it better to have very rigid links that don't allow any give in the rod link itself, while me thinks it better to only make the rear low link robust and the other two on spindly stalks that give with the frame twist but only a very little and prevent any rebound just instant return to neutral state, no cyclic bothers at all, yet acts like another suspension for side ways loads. A big part of my hobby is finding bike limits then behaving within that. Ain't found the end of Peels handling yet nor any way to upset her. If she transmitted vibes then would only be good as track day bike not daily commutes or long range trace inducer. Part of THE Hinge onset is the tire conflicts, front aimed one way with resistance while rear aimed another while trusting. The Commando has the potential to conform it self to tire conflict loads, which has potential of making it maybe the best handling cycle yet produced, with some simple mods. Not much is mentioned about traction pulses but I find the isolastics act like a traction damper, which makes for more grip on hi power leans.

grandpaul said:

lynxnsu said:

Click to expand...

I like it, but it still needs rod-linked limiting structure; rubber is rubber and allows torsional and lateral movement that we don't really want in a swingarm's rotational foundation.

Click to expand...

lateral movement is elliminated by the design of the iso's (std) , i thought everyone knows about this so no more needs to be said.......

the reason mine are so far backward is this; the swingingarm/rearwheel are feeding all these forces into the engine/cradle /gearbox/rearwheel
the front iso and the rear one are above the swingingarm-level ,any movement is then likely to happen underneith so the 3rd iso is right under the rear std one and triangulates it , the front is taking a lot more punishment now as there is a longer leverage (rear wheel to front iso) so has to be checked more often
this is simple logic , no nerds needed