Dave Taylor Headsteady

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rbt11548 said:
Hi Dave, how are you,? did you get your headsteady up and running?, you mentioned the isos in your post, obviously the side movement is dispensed with when fitting a DT or similar headsteady, how would you then adjust the isos if you can't lever the engine to the side?, by just adjusting until there was a gap?
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Hi Robert, yes, I fitted my Taylor type head steady last year but I had not fitted the spring device, nor had I renewed the rear isolastic, which has made a big difference to the ride quality. I recently fitted the Mark 3 spring device, but in order to say if it alone has made a difference, I should disconnect it and road test it, and then test it at different tension levels. At the moment, vibration is significantly reduced below 2000 rpm and there is a bit more of a buzz at 3000 rpm upwards, compared with the standard Norton head steady, but it doesn't bother me when cruising at 75 mph (approx. 4000 rpm).

I adjusted the isolastics with the head steady disconnected, the bike sitting vertically, off the centre stand. Once that was done, I re-connected the steady to ensure that there was no lateral preload on the isolastics. Since I had dismantled the rear of the bike to get at the rear isloastic, I had a good opportunity to check if the rear wheel was vertical, with a long straight length of angle clamped the side of the rear wheel rim. This method is good enough for me and I am happy with the handling. (I had previously straightened the swinging arm and rebuilt the wheel to the correct offset).

rbt11548 said:
The wheels are also mentioned, are they really going to be that far out of alignment on the vertical that a standard roadgoing bike would have it's handling drastically affected?
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If the swinging arm is bent, yes, that could throw the rear wheel out to a level that affects handling. Also, if the rear engine bolt is a sloppy fit in the isolastic tube, which could allow the cradle to sag in the frame, or if the iso rubbers have deformed over a long time.

What does your bike feel like to ride? Were you happy with the handling before you read this thread?! Do you have a reference point, such as riding someone else's Commando? If you're happy, then ride on! Scotland has great roads and wonderful scenery. I want to visit again some time this year, but one has to be lucky with the weather! If you plan to be in Dublin at any stage, PM me and you can throw a leg over my bike and see what you think.
 
I concur with Ludwig. I was out for a spin yesterday with four guys on modern sports bikes and I didn't feel out of place. On wide, straight main roads, the Commando runs out of puff, but nadgery roads even things up somewhat.
 
Trying to fit my DT unit right now, perhaps a neophyte question but, should the frame clamp (after tightening) still be loose enough to move on the frame tube? Also, whats the ideal amount of movement on the rose joint? Fore & aft? .5" or so?
 
acadian said:
Trying to fit my DT unit right now, perhaps a neophyte question but, should the frame clamp (after tightening) still be loose enough to move on the frame tube? Also, whats the ideal amount of movement on the rose joint? Fore & aft? .5" or so?
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Uh, no movement. Hence one of the great faults with a clamped configuration.
 
swooshdave said:
acadian said:
Trying to fit my DT unit right now, perhaps a neophyte question but, should the frame clamp (after tightening) still be loose enough to move on the frame tube? Also, whats the ideal amount of movement on the rose joint? Fore & aft? .5" or so?
Click to expand...

Uh, no movement. Hence one of the great faults with a clamped configuration.
Click to expand...

great... what's been used as shim material between the clamp and the tube then? Also, what's your experience on the for & aft movement of the joint? Half an inch or so?
 
acadian said:
swooshdave said:
acadian said:
Trying to fit my DT unit right now, perhaps a neophyte question but, should the frame clamp (after tightening) still be loose enough to move on the frame tube? Also, whats the ideal amount of movement on the rose joint? Fore & aft? .5" or so?
Click to expand...

Uh, no movement. Hence one of the great faults with a clamped configuration.
Click to expand...

great... what's been used as shim material between the clamp and the tube then? Also, what's your experience on the for & aft movement of the joint? Half an inch or so?
Click to expand...

It sounds like you might have one of the 'Italian Frames'. The tubing is metric on these frames, the original frames are 1". 1" being 25.4mm, and the tube in question being 25mm, it's 0.4mm (0.016") undersize to the clamp. You could use aluminum from a can, the ('Persig Shim'), but it might be too soft. I had some stainless 0.010" shim and it took a full wrap just fine. You should probably strip off the paint where the clamp is going in any case, and a dab of Loctite couldn't hurt.
 
I read all about this last year before I bought the DT headsteady. I also read all about Italian frames.

I bought a DT headsteady.

My bike has an iItalian frame. To quote UK NOC: I can tell you that the Frame No. with the prefix F means that the frame was manufactured by Farina in Italy

The bare-metal frame tube was measured just after I sandblasted the frame and it measured 25.4mm, i.e. a very Imperial 1"

With primer and paint applied (not powdercoat), the headsteady clamp would bear up against itself before it fully clamped onto the frame, and could turn without any real effort.

This isn't very good, and lets down an otherwise very high quality product.

The minimal a gap is evident here at the 4 O'clock position - this is after I re-worked the clamp

Dave Taylor Headsteady


My analysis of the situation is that the headsteady clamp halves are bolted together then bored (accurately, IMHO), but because no temporary shims are fitted in the clamped assembly for the boring process the clamp doesn't act as a clamp - it behaves more like a big-end,....not good!
To remedy the problem I filed off a small amount of material from the face of one of the clamps, which allowed the assembly to clamp the frame correctly.
I'm minded to go back and take more metal off, but it is clamping properly.

Despite this typically British piece of engineering, i.e., nearly perfect ;) I believe the DT headsteady with spring device is the best solution available, provided this fault is understood and dealt with appropriately.
The fact that the clamp can rotate (before being clamped, that is!) does make setting up a lot simpler. I sat on the bike with the headsteady loose, and it was remarkable to note that if the bike was leant over by any amount, the top end of the motor visibly moved.
With the 'fettled' DT clamp in place, the rose-joint could turn easily enough when the bike was totally vertical, yet would stiffen up as soon as any lean was introduced.
It certainly made me appreciate the need for the additional control provided by the linkage. The spring device (as has been posted elsewhere recently) also allows the Isos to operate without undue pre-load.

Dave Taylor Headsteady


I don't believe the beer-can shim is the right answer here - not for my frame, anyway :?
 
B+Bogus said:
Dave Taylor Headsteady


With the 'fettled' DT clamp in place, the rose-joint could turn easily enough when the bike was totally vertical, yet would stiffen up as soon as any lean was introduced.
It certainly made me appreciate the need for the additional control provided by the linkage. The spring device (as has been posted elsewhere recently) also allows the Isos to operate without undue pre-load.

Dave Taylor Headsteady


That's exactly what was happening to mine, easily turning whilst vertical, me sat on the bike, off all stands, and slight stiffening up ,(OOH Matron!), when leant over.
When you mention machining a bit of theface of the headsteady do you me from the flat face?
What length did you set your spring at?
Cheers
Robert
Click to expand...
 
B+Bogus said:
I read all about this last year before I bought the DT headsteady. I also read all about Italian frames.

I bought a DT headsteady.

My bike has an iItalian frame. To quote UK NOC: I can tell you that the Frame No. with the prefix F means that the frame was manufactured by Farina in Italy

The bare-metal frame tube was measured just after I sandblasted the frame and it measured 25.4mm, i.e. a very Imperial 1"

With primer and paint applied (not powdercoat), the headsteady clamp would bear up against itself before it fully clamped onto the frame, and could turn without any real effort.

This isn't very good, and lets down an otherwise very high quality product.

The minimal a gap is evident here at the 4 O'clock position - this is after I re-worked the clamp

Dave Taylor Headsteady


My analysis of the situation is that the headsteady clamp halves are bolted together then bored (accurately, IMHO), but because no temporary shims are fitted in the clamped assembly for the boring process the clamp doesn't act as a clamp - it behaves more like a big-end,....not good!
To remedy the problem I filed off a small amount of material from the face of one of the clamps, which allowed the assembly to clamp the frame correctly.
I'm minded to go back and take more metal off, but it is clamping properly.

Despite this typically British piece of engineering, i.e., nearly perfect ;) I believe the DT headsteady with spring device is the best solution available, provided this fault is understood and dealt with appropriately.
The fact that the clamp can rotate (before being clamped, that is!) does make setting up a lot simpler. I sat on the bike with the headsteady loose, and it was remarkable to note that if the bike was leant over by any amount, the top end of the motor visibly moved.
With the 'fettled' DT clamp in place, the rose-joint could turn easily enough when the bike was totally vertical, yet would stiffen up as soon as any lean was introduced.
It certainly made me appreciate the need for the additional control provided by the linkage. The spring device (as has been posted elsewhere recently) also allows the Isos to operate without undue pre-load.

Dave Taylor Headsteady


I don't believe the beer-can shim is the right answer here - not for my frame, anyway :?
Click to expand...
Exactly what I needed.... Thanks!!!
:mrgreen:
 
"I bought a DT headsteady.

"Despite this typically British piece of engineering, i.e., nearly perfect ;) I believe the DT headsteady with spring device is the best solution available, provided this fault is understood and dealt with appropriately."


Good that you sorted the clamp. May I suggest that the nut you've located between the rose and clamp face be relocated to the opposing side of the clamp? It's function is as a jamb nut on the post (screw to clamp).

Your earlier query re fore & aft play at that joint went unanswered. The rose should butt up firmly against the clamp. (There is no need for a "movement space" here between the joint and clamp. Your picture shows how you can then align the rod link to parallel alignment across the planes of the base - fore, aft, up, down. (At the moment the rod is far from parallel.) You would then position (slide fore/aft and rotate cw/ccw) the clamp via that new parallel link position, then clamp down. This is how the clamping, rotating arm is designed to permit optimal alignment of the rod across the plane of the motor mounting surface. You may now observe that the rod length must be lengthened or shortened in order to permit the clamp arm to arrive at its necessary position. Before committing the clamp to the position you establish, place the gas tank and check for clearance between the clamp arm and the tank. If they interfere, then readjust as needed.

cheers
 
As mentioned in the first post on this thread, I had to use additional spacers between the joint eye and the clamp in order to effectively push the clamp forwards. If this is not done then the mounting pillar affixed to the head will contact the clamp on the tube above with the link set horizontal and at 90° to the frame axis.

The top tube clamp was a perfect fit on my Andover replacement frame. It is a pity that alternative clamps are not available to take account of the frame differences.
 
"As mentioned in the first post on this thread, I had to use additional spacers between the joint eye and the clamp in order to effectively push the clamp forwards. If this is not done then the mounting pillar affixed to the head will contact the clamp on the tube above with the link set horizontal and at 90° to the frame axis.

The top tube clamp was a perfect fit on my Andover replacement frame. It is a pity that alternative clamps are not available to take account of the frame differences."

July 08 Classic Bike piece on the genius of Henry Maudslay, 1771 - 1831, (one of the key creators of the modern machine/ screw-cutting lathe) was praised by a contemporary thus - "It was a pleasure to see him handle a tool of any kind, but he was quite splendid with an 18-inch file"

The solution to that alignment issue is simply to file and reshape the top surface of the clamp at an angle equal to the angle of the frame backbone tube it comes in conflict with. If you don't align the link, then you can't expect it to perform properly. The "fix" is a simple and satisfying process to make a kit part fit your particular situation properly.

cheers
 
B+Bogus said:
My bike has an iItalian frame. To quote UK NOC: I can tell you that the Frame No. with the prefix F means that the frame was manufactured by Farina in Italy
Click to expand...

I've never heard any mention of the name 'Farina' before in connection with the Italian-made Commando frames, only Verlicchi?: http://www.verlicchi.it/eng/
 
RedRider1971 said:
July 08 Classic Bike piece on the genius of Henry Maudslay, 1771 - 1831, (one of the key creators of the modern machine/ screw-cutting lathe) was praised by a contemporary thus - "It was a pleasure to see him handle a tool of any kind, but he was quite splendid with an 18-inch file"

The solution to that alignment issue is simply to file and reshape the top surface of the clamp at an angle equal to the angle of the frame backbone tube it comes in conflict with. If you don't align the link, then you can't expect it to perform properly. The "fix" is a simple and satisfying process to make a kit part fit your particular situation properly.

cheers
Click to expand...

Thanks for the advice. I'm actually quite adept at handling big bastards (little f**kers as well, but that's another story). :)

The clearance problem is not between the clamp and the frame backbone but between the clamp and the socket screw protruding above the vertical pillar mounted to the head and which holds the horizontal eye. If you look at B+'s second photo, you'll see how close these items are to each other, even with the spacer nut fitted and as a consequence of the engine movement, there has to be more than just a few thou clearance at a static position.

If I were to take my big bastard and start removing metal, this would either have to be from the rear face of the frame clamp or from the top of the pillar but as the former would necessitate thinning this to about half the original dimension, I would prefer not to do so, not least because the clamping screws pass through this area.

The second possibility, of lowering the pillar, would result in the clamp having to be turned clockwise to restore horizontal alignment and this would bring the mounting centres closer to each other resulting in an impossibly short tie rod.

It may be possible to get round this by completely re-drawing the frame clamp but that would bring a further round of experimentation and all just to avoid spacing the rod end slightly from the clamp.
 
L.A.B. said:
B+Bogus said:
My bike has an iItalian frame. To quote UK NOC: I can tell you that the Frame No. with the prefix F means that the frame was manufactured by Farina in Italy
Click to expand...

I've never heard any mention of the name 'Farina' before in connection with the Italian-made Commando frames, only Verlicchi?: http://www.verlicchi.it/eng/
Click to expand...

Maybe not LAB, but they did make a good job of styling the Austin Cambridge ! :)

I've never been able to pin down a definite link between F prefixes and metric tubes. There are 750 frames with no 'F' that are clearly metric and 850 'F' frames which appear to be imperial.
 
"The clearance problem is not between the clamp and the frame backbone but between the clamp and the socket screw protruding above the vertical pillar mounted to the head and which holds the horizontal eye. If you look at B+'s second photo, you'll see how close these items are to each other, even with the spacer nut fitted and as a consequence of the engine movement, there has to be more than just a few thou clearance at a static position."

Okay. If you look at that picture, imagine removing the nut from between the clamp and the joint face. Without moving the clamp from its position on the frame tube, you can see how the rod would be able to rotate anti-c/w about the "pillar". You can see that there is sufficient space between the clamp's current position and the back side of the spring ass'y if further space between the pillar and the clamp is needed. As the clamp remains in its current rotated position it will not abutt the pillar/joint/screw ass'y.
 
Tintin said:
Third and final point: Isos vs. Rods in general. The isos are planar sliding guides, rods are spherical. Rubbers support the weight, rod's don't (well, not at that angle). From an engineering POV I'd prefer three isos with detail improvements on the guides over these mixed designs. Or as I said before a setup with three rubbers and four (!) parallel rod-ends of equal length. However when I last mentioned this somebody answered that this is nice in theory but the Commando frame flexes quite a bit - and I have to admit that I agree..... :wink:

That's it for me regarding this so if this thread RIP - fine by me.... :roll:


T
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I've made some of the detail improvements you mention on the iso's to the n'th degree. I made endcaps for the front and rear out of 1/4" 4130 with wider and thicker abutments because the originals cave in over time. I got rid of the doughy PTFE washers and replaced them with acetal/teflon, which is much harder. I put in Hemmings adjusters front and rear on both sides. Turned down a set of 5 rubber bushes to fit in the rear, I read somewhere that Mick did that on a race bike once. For the headsteady I replaced the sideplates with thicker stainless and made a stud that didn't take the shearing force on the threads and shimmed the thing in every dimension to get it right. After all that fun, and it really was a lot of fun, I've come to my personal conclusion the the basic concept of using endcaps alone to control or register the cradle is bankrupt. The reason is that they don't line up in any one plane, let alone the centerline. Only the opposite iso's are loaded at any one time so the load path goes from one side to the other.

Mixing iso's and rods doesn't seem to be a problem to me in itself. In fact, one rod linkage at the centerline makes the job that the iso's are trying to do much easier. I'm using a linkage under the swingarm and one at the headsteady, along with the front and rear iso's. The DT headsteady is an engineering abomination in a lot of ways and I'll probably make one next winter, but for now it seems to be sufficient. After Dreer installed an iso under the trans he was running with no headsteady at all and it seemed to be sufficient. After years of having fun tinkering, sufficent has become my new byword. Although, nothing exceeds like excess 8)

P.S. By the opposite iso's being loaded at one time I meant that the rear right will be stressed while the front left is, and visa versa. The worst culprit is the rear iso. It's like having ball joints basically spread out from the centerline.
 
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