The World's Straightest Commando

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john robert bould said:
The reason why "parts" are replaced is down to the owners . Regarding my dampers and proberly less than 1/2 percent of total commandos.
When some [not all] have spent thousands on the available goodies..brakes, heads, carbs ,belt drives ,engine internals etc ..then go out on the road and hear that Fork clonk ..that starts to get annoying ...thats why they fit the damper kit. On the other hand some like the general feel ,mayby the 400 road users and 15 racers are just happy :?:



Jose Refit said:
John,

I totally agree that just about any structure you can think of will flex. But from an engineering/common sense perspective what would be the best starting point for a motorcycle chassis - everything as intended, or wheels, steering head, swinging arm etc all mis-aligned to each other? Permanent distortion is one thing but a frame which momentarily flexes and then returns to it's original (straight) state is another. I find it difficult to believe anybody wallowing and weaving through curves on a motorcycle and so limiting it's performance is not going to care - especially after spending several thousand $'s, £'s or whatever on that motorcycle. This isn't joy, IMHO it is a badly engineered motorcycle and an accident waiting to happen. I'm curious, what would be the point of someone fitting a set of improved fork dampers to a motorcycle with a "distorted" frame?

yours, incredulously, Jose.
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I have your Landsdowne kit in my forks. There is more that can be done to the forks than just the damper kit although there is a point of diminishing return. I know there is extreme disagreement with fitting a fork brace to a Commando, mainly because they are difficult to adjust properly. But I have been able to get the fork tubes to slide smoothly with a brace installed. My bike has not hit the road yet so can't determine if this will work long term, but I am assuming if the forks slide smooth in the shop and everything is tight they should remain so over time. In my opinion this will go a long way towards reducing some of the "flex" and looseness of the Commando forks discussed earlier. I also installed the Turcite fork bushings to reduce stiction. I have no testing to back up my opinion so you all can rip me apart if you chose, but I believe that if we "can" make improvements we should try to.
 
Jose Refit said:
john robert bould said:
The reason why "parts" are replaced is down to the owners . Regarding my dampers and proberly less than 1/2 percent of total commandos.
When some [not all] have spent thousands on the available goodies..brakes, heads, carbs ,belt drives ,engine internals etc ..then go out on the road and hear that Fork clonk ..that starts to get annoying ...thats why they fit the damper kit. On the other hand some like the general feel ,mayby the 400 road users and 15 racers are just happy :?:



Jose Refit said:
John,

I totally agree that just about any structure you can think of will flex. But from an engineering/common sense perspective what would be the best starting point for a motorcycle chassis - everything as intended, or wheels, steering head, swinging arm etc all mis-aligned to each other? Permanent distortion is one thing but a frame which momentarily flexes and then returns to it's original (straight) state is another. I find it difficult to believe anybody wallowing and weaving through curves on a motorcycle and so limiting it's performance is not going to care - especially after spending several thousand $'s, £'s or whatever on that motorcycle. This isn't joy, IMHO it is a badly engineered motorcycle and an accident waiting to happen. I'm curious, what would be the point of someone fitting a set of improved fork dampers to a motorcycle with a "distorted" frame?

yours, incredulously, Jose.
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Click to expand...




Jose , wellcome to 2014 ! if you still believe brazing up and re drilling works, :lol: can you explain how?

Extended top bushes and repositioned hole in the damper tube gets rid of bottoming and topping out problems. Don't see how your kit addresses these design problems unless it includes extended bushes and a replacement damper tube,

Yours, over and out and thanks for all the fish, Jose.
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Alrighty comnoz I thought you wise enough not to press luck in public but you have a good sense of how nicely the rump rod handles everything thrown at frame by wind and tire angle loads. Reflect on the thrilling G load stress of decreasing radius - that's the handling & braking banes of all other cyclers but for me on Ms Peel and parking lot stunt riders, a few I've seen do complete programs never counter steering at all. To tackle decreasing radii requires teeth to butt gritting charging into them on purpose if not already past point of no return into 'bad' surprise blind one. Decreasing radii separates the wimps from the winners and proves trail braking is for dummies on corner cripples. It takes power to corner harshly and more so to tackle decreasers so must use hi accelerating power that lifts forks to full extension and tire out of much or any traction. To tackle decreasers you have to cause cycle to fall over on its own and try to save that. Its a transition state that jerks forks into direct road following out of counter steering away form center and puts a horrific twist force in frame that's suddenly relieved. That's what I mean by Peel's Road Orgasms, build ups and releases you better have full control of or splat into a mess. Once rest of world catches up with the potential of One rear robust rod + 2 helper compliant inked isolastic Commando they will realize fork dampers and super duper fork innards are only needed to compensate for bad design behavior but do not solve the real issue of tail wagging the head nor allows transitioning into straight steering hooked up loads on purpose.

I found the rump rod is main feature that allows this unicycle control and also what everyone else is trying to compensate from by fork mods -
Severely decreasing radii also reveal how dangerous it is to depend on front tire to steer. As power increased front lightens up so becomes more sensitive to the tail patch slapping forks so poor logic to hobot - like controlling craft speed by the speedometer needle which should be left free to only be an indicator of what rear is thrusting and not interfere with rear when its not in some traction assisting rear thrust vectoring. One can't live in public long in those states so I mostly savored Peel's bigger heavier smoother battle ship size inertial dampened sense better than the Goldwings I've ridden as passenger.
 
Unclviny said:
Who does this in the U.S.A.?

Vince
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I bet FrameCrafters (http://www.framecrafters.net) in Union Illinois could easily do this type of work. If I ever had my Commando down to a bare frame I'd let them inspect it.
I've had them fix cracks in my Alloy gas tank and cracks in my Ducati 900SS frame.
They have quite an impressive shop and reasonable prices. Good guys.
 
L.A.B. said:
Jose Refit said:
Extended top bushes and repositioned hole in the damper tube gets rid of bottoming and topping out problems. Don't see how your kit addresses these design problems unless it includes extended bushes and a replacement damper tube,
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Whilst those mods do go some way to alleviating the topping and bottoming problem (neither does it particularly successfully, in my opinion and yes, I've tried both) they do not address the problem of lack of proper controlled damping, which the Lansdowne kit does because it is a complete damper system which doesn't rely on the fork bushes acting as the extension stop.
The Lansdowne kit is a considerable improvement over the aforementioned mods in my, and I'm sure may others' opinion who have fitted the kit.

http://www.lansdowne-engineering.com/
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L.A.B,

You're incorrect on a couple of points. I've done the mod and it works so well I now use SAE5 fork oil without bottoming or topping plus gives good response to road inputs. Maybe you mis-read the instructions or your tolerances are too big. The Roadholders do have controlled damping. On extension damping is controlled by oil forced out between the damper rod and damper tube cap. On compression damping is controlled by oil forced between the damper tube and dished valve at the bottom of the damper rod. Crude but effective. But then the Landsdowne's are hardly state of the art - relying on oil forced past tapered needles I believe. Granted, Roadholders are not easily adjustable but different viscosity oil gives different damping characteristics so therefore adjustable within limits. We are talking about a 68 year old design here so don't expect Showa type damping. Modern forks give variable (as well as adjustable) damping which alters depending on the rate of compression or extension.

http://www.cosentinoengineering.com/ind ... age450.htm

Yours, sans jarring, Jose.
 
john robert bould said:
Dead right , not yet in Moto GP bikes ,only 400 road and 15 racers, cheesy you get back to the welder... :lol:
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John,

I disagree, the technology is not new. Shim stacks within the cartridge give the variable damping as the forks compress and extend, fast or slow. The Consentino dampers have them, I believe they're modified Honda CBR 600 units and have been around for maybe 10 years so the GP bikes will have them, even push bikes have them http://www.pinkbike.com/news/To-The-Poi ... -2013.html

Jose.
 
Jose Refit said:
L.A.B,

You're incorrect on a couple of points. I've done the mod and it works so well I now use SAE5 fork oil without bottoming or topping plus gives good response to road inputs.
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I don't accept your view that I'm "incorrect" as I can speak from my own experience and I don't entirely agree with your findings.

Jose Refit said:
The Roadholders do have controlled damping. On extension damping is controlled by oil forced out between the damper rod and damper tube cap. On compression damping is controlled by oil forced between the damper tube and dished valve at the bottom of the damper rod. Crude but effective. On compression damping is controlled by oil forced between the damper tube and dished valve at the bottom of the damper rod.
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Crude? Yes. Effective, reasonably effective but can be vastly improved upon in my opinion.


Jose Refit said:
But then the Landsdowne's are hardly state of the art - relying on oil forced past tapered needles I believe.
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Maybe not, but the Lansdowne dampers are far better than the original system, with or without 'mods'.


Jose Refit said:
We are talking about a 68 year old design here so don't expect Showa type damping.
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I can only suggest you try a set of Roadholders fitted Lansdowne dampers then.
 
Peel is experimental in a number of ways and eventually want to try Landowne wonder forks to see if helps spank sports bikes and get to pavement better than curd modified factory guts. Will praise em a lot if they do.

Back to frame issues once iso tubes, axles and stem perfect, what about frame re-enforcements to keep them in controlled relations on frame testing cornering? Ken Canaga review implies all vintage frames raced to win get distorted or cracked in a few seasons, how can we lessen that or can we?
 
L.A.B. said:
Jose Refit said:
Jose Refit said:
We are talking about a 68 year old design here so don't expect Showa type damping.
Click to expand...

I can only suggest you try a set of Roadholders fitted Lansdowne dampers then.
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L.A.B,

Showa cartridges (and other modern units) feature shim stacks so the Lansdowne units cannot provide variable, Showa type, damping. The only improvement I can see over standard Roadholders is the Lansdownes are easily adjustable,

Yours, fixedly damped, Jose.
 
Jose Refit said:
the only improvement I can see over standard Roadholders is the Lansdownes are easily adjustable,
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Then I'd have to say you were "incorrect".
 
L.A.B. said:
Jose Refit said:
the only improvement I can see over standard Roadholders is the Lansdownes are easily adjustable,
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Then I'd have to say you were "incorrect".
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L.A.B

inaccurate maybe but not wrong, they have fixed damping in use - same as Roadholders, what ever the web site claims,

over and out, Jose.
 
Jose Refit said:
inaccurate maybe but not wrong, they have fixed damping in use - same as Roadholders, what ever the web site claims,
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The website claims are certinly more accurate than your speculation from which it's apparent you've had no direct experience of the Lansdowne kit.
 
I hope no one drains off the recommended 20 weight [Stock Norton] and refills with sae 5 weight as cheesy recommends. But as cheesy is right what have you to lose? Must email and tell Duncan , some how i carnt see him rushing into the workshop and swapping the dampers back to stock...and filling up with 5's oil? plus why would Rob Mckeever ,one of the most respected Racers in the US ,tell me what ever oil grade he had tried could not tame his Manxs ..with 4 bikes and 60 years experiance ..i guess he should know, any way whats this "crude" remark, Duncan reported the dampers where simple..but effective...and he should know, now completed five seasons . and Peter Crew winning his class ... Which made me proud...because i had replaced his HONDA SHIM system ...repeat replaced his Honda shim damper..and he got second. with his RS 125 .completing only 1/2 of the races :!: .


L.A.B. said:
Jose Refit said:
the only improvement I can see over standard Roadholders is the Lansdownes are easily adjustable,
Click to expand...

Then I'd have to say you were "incorrect".
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john robert bould said:
...because i had replaced his HONDA SHIM system ...repeat replaced his Honda shim damper..and he got second. with his RS 125...
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Is that the Honda shim damper which is....

john robert bould said:
....not yet in Moto GP bikes......
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A bit of consistency wouldn't go amiss,

Yours, wondering what is the point, Jose.
 
this constant posting reminds me of Phil Yates...any connection?



Jose Refit said:
john robert bould said:
...because i had replaced his HONDA SHIM system ...repeat replaced his Honda shim damper..and he got second. with his RS 125...
Click to expand...

Is that the Honda shim damper which is....

john robert bould said:
....not yet in Moto GP bikes......
Click to expand...

A bit of consistency wouldn't go amiss,

Yours, wondering what is the point, Jose.
Click to expand...
 
I only had to read the first few pages of this topic and I was exhausted. Its getting a bit out of line, so locking it down.
Please remain civil and try to stay on subject with useful information.
 
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