Rod Linkage Head Steadies and Vibration

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1up3down

1up3down

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because the stock head steady's rubberiness allows more side to side movement of the motor(head) than the aftermarket rod linkage type does it not follow that there IS more vibration transmitted to the frame with the rod linkage set up?

with both my previous Dave Taylor and now my CNW head steadies transmitting more vibration than the stocker

anyone have a different perception?

......putting aside the better handling rod advantage I feel as irrelevant to this vibration issue......
 
My experience is that the 73 on boxed stock headsteady was superior to the rod link units. If you want the best of both worlds, minimal vibration and superior handling, I found the PR iso headsteady from Norvil to be awesome. Very smooth, yet a nice tight feel. And yes, it is like sex.

http://www.norvilmotorcycle.co.uk/061484SS.htm
 
I didn't notice any difference in my home made rod linkage setup than the old 69 setup. The additional spring did cut out the idle vibrations though.

Dave
69S
 
A really good design when the head steady affects the handling ? - UNBELIEVABLE ! ! !
 
1up3down said:
because the stock head steady's rubberiness allows more side to side movement of the motor(head) than the aftermarket rod linkage type does it not follow that there IS more vibration transmitted to the frame with the rod linkage set up?

with both my previous Dave Taylor and now my CNW head steadies transmitting more vibration than the stocker

anyone have a different perception?

......putting aside the better handling rod advantage I feel as irrelevant to this vibration issue......
Click to expand...

Engine doesn't shake side to side, it goes up and down.

The side load is from the rear wheel although probably mostly taken by the main isolastics.
 
Swoosh, if the motor does not move side to side then what is the purpose of stopping it from doing so with the rod linkage type head stead which clearly is designed to do exactly that while allowing for up and down movement?
 
1up3down said:
Swoosh, if the motor does not move side to side then what is the purpose of stopping it from doing so with the rod linkage type head stead which clearly is designed to do exactly that while allowing for up and down movement?
Click to expand...

As I said, to keep the rear wheel from moving from side to side.
 
1up3down said:
because the stock head steady's rubberiness allows more side to side movement of the motor(head) than the aftermarket rod linkage type does it not follow that there IS more vibration transmitted to the frame with the rod linkage set up?

with both my previous Dave Taylor and now my CNW head steadies transmitting more vibration than the stocker

anyone have a different perception?

......putting aside the better handling rod advantage I feel as irrelevant to this vibration issue......
Click to expand...

You are the first one to tell me my head steady causes more vibration with 4 hundred some sold. Road feel [roughness] does increase. Are you sure the vibration is not coming from another source- like new isolastic mounts.

Do you have an original headsteady to compare the vibs? Jim
 
comnoz said:
1up3down said:
because the stock head steady's rubberiness allows more side to side movement of the motor(head) than the aftermarket rod linkage type does it not follow that there IS more vibration transmitted to the frame with the rod linkage set up?

with both my previous Dave Taylor and now my CNW head steadies transmitting more vibration than the stocker

anyone have a different perception?

......putting aside the better handling rod advantage I feel as irrelevant to this vibration issue......
Click to expand...

You are the first one to tell me my head steady causes more vibration with 4 hundred some sold. Road feel [roughness] does increase. Are you sure the vibration is not coming from another source- like new isolastic mounts.

Do you have an original headsteady to compare the vibs? Jim
Click to expand...

I would like to hear if anyone else has noticed this.
 
If there is any increase, it is negligible. I don't notice any objectionable vibration.

In theory, perhaps when a side load is applied during cornering, some of the engine's vertical shake might get transmitted horizontally . . . .
 
I know my bike vibrates all the time. It has every since I made it larger. First as a 920 and then after I got tired of trying to keep that together I installed heavy Venolia 880 pistons.

My wifes stock mark 3 on the other hand is extremely smooth. I have done trips on it with and without the rod end steady and I can't feel any difference in vibration.

I would not expect there to be any difference in vibration between my head steady and the Dave Taylor headsteady. I would suspect that if installing a rod end headsteady increases the vibration then there must be something else going on.

If the engine shakes side to side because of a "rocking couple" then I would expect my headsteady would transmit more vibration to the frame. A rocking couple can be created by a crank with dynamic balance problems, compression differences, valve or ignition timing differences or things as simple as carburetor balance. Some things to check first would be compression and then compare spark plug colors. If one cylinder is pulling harder than the other then the engine will rock from side to side. Jim
 
Top knot rod links should not transmit vibration but eliminate some of it, if.
a. the length of the radius is enough its small arc don't bind the eyes
b. adjuster length is set to stay at neutral most slack loose swivel state
c. link is not touching anything but its attachment points
 
There is an article in last month's? Roadholder in which a member wrote a very detailed account of how to properly set the isolastics. Due to the small clearances normally used in setting iso gap, any twisting of either isolastic mount will transmit more vibration.

By carefully measuring and setting up the engine mounts, one can have a low-vibration Commando with excellent handling. The guy who wrote the article took time to even shim the isos so the drivetrain tracks true with the frame, and runs about half the clearance with very little vibration.

If nothing else, try just following this procedure:

Bike should be propped up on stands -not the center stand. you want only the weight of the engine in the cradle

Loosen all mounts

Tighten rear isolastic to zero clearance
Tighten front isolastic to zero clearance
Set head steady
Back off front iso to standard clearance
Back off rear iso to standard clearance

If you have excessive vibration up to 3000 RPM, the rear is tight
If you have vibration from 3000-5000 RPM, the front is tight
If you have vibration throughout the range, both are tight
 
any twisting of either isolastic mount will transmit more vibration.
Click to expand...

Boy Howdy if ya ever get slammed to feel them twist up then spring back. When able to, stick a screw driver in there, don't have to be a very HD one either and lever on a tab. I get at least a mm deflection that seems to be the long tubes themselves twisting. The tabs themselves seem to be robust enough not to deflect to matter. A down tube cross brace reduced this deflection in Peel. It was worth a bit less spring back reaction, in states every stilly little mm too much or not enough in need of time => bad juju.

There is about a decade of variety of top helm joint radius links with a majority reporting no increase in or even a decrease in vibration. By now I'd expect the word to have gotten out on type or version to be shy and died out already. Implies something different in the Cdo's concerned & or the way installed and adjusted. I know for sure my Trixie's under tube is bent to LH ~1/4". Factory cylinder tops are all .003 out of even to base, towards the rear IIRC, but that shouldn't matter. Then the head top hole bosses may be out of square to anything else but that shouldn't matter at least by its lomesome.
 
rpatton said:
Bill, who wrote the article?
Click to expand...

Now that I need it, I can't find the issue. It must be in the January 'Roadholder', as that's the one issue I can't find. I looked at the NOC website, but they don't post Roadholder issues online, only reference pics of what each issue looks like and the main articles, and it's about 6 months delayed.
 
Bill, Thanks for looking. In a way it sounds like 'The World's Straightest Commando'. It's like saying 'The World's Straightest Piece of Linguini'. It's meaningless to have a discussion in terms of 0.001" about a frame that flexes as much as a Commando. It explains why some things work and others don't. I've gone to great lengths and in the end, a good headsteady is the best bang for the buck. All the rest could be a definition of 'diminishing returns'.

http://vintagenet.us/phantom/wsc.html
 
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