Head steady vibration

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BJM

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Dec 2, 2012
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Is there any general consensus on increased vibration with non standard head steadies. I'm thinking of getting something to replace the standard 74 850 set up but I've heard some of them after market ones result in increased vibration.
Maybe general consensus was the wrong phrase. Any opinions from experience ?
 
Good Q. I have the Dave Taylor type, but haven't installed it for just that reason. The "hinge" in the bike doesn't seam to reduce my cornering ability, so it's not urgent to me. I'll be interested to read the reports.
 
You could get one of Jim's from CNW...
Head steady vibration
 
You could get one of Jim's from CNW...
Click to expand...

I have one of Jim's from CNW, for over a year now

It does not reduce vibration, and neither did my Dave Taylor before the CNW one.

What it does do it prevent the head (motor) from moving side to side while allowing it to move fore and aft and up and down. The advantage is that when the bike is leaned over the motor does not "fall" off to the side, far better held in place than the stock head steady,
and this is a very positive effect on cornering, a more secure feeling, what some say is like being on "rails".

The Jim CNW head steady is far more robustly made than the Dave Taylor, which should then in theory mean far less replacement of the movable linkage parts. It is also twice the cost of the DT, but you can say that you get what you pay for.
 
I bought one of Jim's through CNW. Works exactly as designed and certainly hasn't increased vibration...
 
The extra isolastic type add more rubber mass which can transmit buzz and often do so reason Norton kept cutting iso cushion in half 3x's till decent low rpm isolation. in 2004 I found the rod links did not transmit vibration if decently aligned and adjusted and the rest is history with many good ones out there or brew ya own. It also takes good tires at hi side of normal air pressures to get best sense of what isolastics and various type steadies are capable of. Softer air &or more aged the tires the more annoying presence of an old fashioned engine gets through. When right not even the valve train buzz gets through like it does on every other supposed smooth modern i've sampled so far.
 
Spend the money. My DT is tops for money well spent plus the iso. bits are not side loaded anymore so last much longer. Handling so tighter. No sideways flexings. Vibrations about the same as before ,she's a shaker that smooths out the faster ya go. :)
 
SO...ARE THE TWO SPRINGS REDUNDANT?
i asumed they "held up the weight" to prevent the ios's getting squashed, basicly keeping the rubbers central.?
 
john robert bould said:
SO...ARE THE TWO SPRINGS REDUNDANT?
i asumed they "held up the weight" to prevent the ios's getting squashed, basicly keeping the rubbers central.?
Click to expand...

Hmmm, feedback when I asked this question was inconclusive.

My conclusion was that it may be advantageous to the iso rubbers on a stock electric start engine unit.
Mine is not elec start and with the belt drive and light clutch the engine unit is probably 10lbs light than stock, and much more so compared to a stock electric start unit.
So I went without the springs and it feels great!
The springs don't look good to my eye though, they basically put the engine under constant tension they are trying to pull the engine up by the head after all. That looks to me to put stresses on the barrel base and crank cases.
All IMHO of course.
 
Spring helps lower low rpm isolation of heavier engine by helping uncompress front cushions that take most the engine hopping action and should not stress the engine fasteners but is extra clutter to view so comnoz under support spring is elegant adaption. Isolastic Commando power unit is a unique fascinating Norton invention that uses engine as a stressed support member w/o stressing the engine very much.
 
Gut feeling the springs place very little stress on barrel bolts...when one bolt will lift 1/2 ton? well just had a look in the book,and one 1/4 HT bolt will break at 2 tons, no idea what the head bolt threads strip at, in the alloy. :?:

Fast Eddie said:
john robert bould said:
SO...ARE THE TWO SPRINGS REDUNDANT?
i asumed they "held up the weight" to prevent the ios's getting squashed, basicly keeping the rubbers central.?
Click to expand...

Hmmm, feedback when I asked this question was inconclusive.

My conclusion was that it may be advantageous to the iso rubbers on a stock electric start engine unit.
Mine is not elec start and with the belt drive and light clutch the engine unit is probably 10lbs light than stock, and much more so compared to a stock electric start unit.
So I went without the springs and it feels great!
The springs don't look good to my eye though, they basically put the engine under constant tension they are trying to pull the engine up by the head after all. That looks to me to put stresses on the barrel base and crank cases.
All IMHO of course.
Click to expand...
 
I did not opt for the spring to be added for my Jim CNW head steady.

In theory it seems harmless and maybe a good idea...
 
john robert bould said:
Gut feeling the springs place very little stress on barrel bolts...when one bolt will lift 1/2 ton? well just had a look in the book,and one 1/4 HT bolt will break at 2 tons, no idea what the head bolt threads strip at, in the alloy. :?:

Fast Eddie said:
john robert bould said:
SO...ARE THE TWO SPRINGS REDUNDANT?
i asumed they "held up the weight" to prevent the ios's getting squashed, basicly keeping the rubbers central.?
Click to expand...

Hmmm, feedback when I asked this question was inconclusive.

My conclusion was that it may be advantageous to the iso rubbers on a stock electric start engine unit.
Mine is not elec start and with the belt drive and light clutch the engine unit is probably 10lbs light than stock, and much more so compared to a stock electric start unit.
So I went without the springs and it feels great!
The springs don't look good to my eye though, they basically put the engine under constant tension they are trying to pull the engine up by the head after all. That looks to me to put stresses on the barrel base and crank cases.
All IMHO of course.
Click to expand...
Click to expand...

I couldn't agree more John, studs would be the last thing to break, same in most engines I guess.

But it does put stress into 'the system' which, someone who has already had a pre through bolt barrel or crankcase break, may wish to avoid.

I'm sure the spring could not cause a failure all by itself, but if I were Alotment for example, who had AN cases break, I'd be looking at all methods of reducing such stress.

When racing Triumph and Nourish engined Dresda's and featherbed framed Bikes, Degans taught me to make very strong head steadies that bolted hard to lugs brazed onto the frame. The head steady would be fabricated with washers between it and the frame, then when it was assembled proper, we'd leave the washers out.
This put the engine under (a fairly mild) constant state of compression. Many racers break Triumph and even Nourish cases. But we never did.
So whilst my spring aversion 'may' be a little OTT, perhaps you can at least see where I'm coming from.
 
Eddie.
Hope you arn suggesting those piddly springs will pull the barrel off is flange? Manx head support acts against the frame bending ,now thats stress :!:
I used to think the frame supported the manx engine...not the other way around
 
I have the Comstock head steady on a 1970 750 "S". Corners like it is on rails and smooth as glass at highway speed. Well worth the money. The stock unit I took off was cracked junk.
 
IMHO the head radius rod besides resisting power unit side leaning, which definitely reduces hing onset, it can also subtract an uncanny sense of annoyance level of road texture through grip vibes and good bit of the wind buffing that also plays though the forks. Still must adjust isolastics pretty close to factory or may buzz on some loads. The more links added away from the isolastic mounts the more flabbergasting fabulous it gets. Play with tire pressure for another level of fine tuning of disappearing deliciousness. i feel Commando can be made smoother with more massive inertial steady sense of nothingness than a Goldwing.
 
B.T,W, you can always remove the spring assembly if you start to worry about it. I like the idea of getting pressures off the forward iso's but obviously it was best developed /applied to the weight of the MK 111 engine.
 
Some find the cushions tend to take a set though not sure ya can detection this expect with radius rod seen mis aligned after a time d/t the sag factor. Peel engine also has Drouin mass to support so hunting up a small air bladder to stuff under and puff up till nicest sense , if I can even tell. I bought spring just in case but threads like this one put me off it extra trouble and view cluttering.
 
BJM said:
but I've heard some of them after market ones result in increased vibration.
Click to expand...

I have installed DT head steadies on a 750 and 850. Does not increase the vibes but moves at what RPM the vibes cut in / out. Still smooth at cruise rpm.
 
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