Dave Taylor Head steady & spring

Hi

I have just installed and adjusted a Dave Taylor head steady on my 72 Roadster 750. Nice.
But I also bought and installed the spring mechanism that is optionally sold with it.
Adjusting tension is easy but what are we adjusting for here?
What is this meant to achieve when adjusted properly?
Instructions regarding the spring mechanism were scant (!!) so any info would help.
Thanks in advance.
Aris

The spring should be tightened up to a specified length. It's in the MK3 manual, I forget the dimension, but it's not a whole lot. That said, I tightened mine up as far as it would go, watching the front isolastic stud collar with reference to the tube end cap with the bike on it's tires, not on the side or center stand. Without the spring, my collar droops down below the center of the end cap by about 1/4" and with the spring fully tightened it droops less than 1/8". What I'm getting at here is it pulls the engine up so the isolastics start off in a more centered situation than compressed to the bottom. I notice it did reduce the low rpm vibrations a whole lot. Can't say it did anything to road speeds vibrations. This is just my opinion and what I found. Others may have their ideas.

Dave
69S

The MKIII manual says 1.47 to 1.53" for the overall installed coil length. But of course that engine/transmission system would have some differences from yours. I suggest that as a starting point, then try adding/subtracting a tenth and see what happens.

Thanks, this makes sense.
But what should I be adjusting for?

Compared to the original head steady (in tatters) which the DT + spring replaced:

1. I now have more vibrations at low RPM, which is not a problem. I would almost dare say, adds character
2. Slightly higher vibes than before throughout the entire RPM range.
3. Almost as smooth as my 6 cylinder Honda CBX at 3,500 RPM

So what more, if anything, should I be doing with the spring adjusted?

P.S. Before you say, the DT head steady and isolastics, are all properly adjusted

Thanks again!
Aris

If you've got 1.5" of coils it's job done!

As Dog T says, it unloads the main isos (especially the front) so they can operate closer to their neutral point, rather than 1/4" below.

The main benefit is better lateral control of the motor (as if you needed reminding ). Changes to the vibration characteristics of the engine are more of a side-effect than a function of the design, if you see what I mean.

I put one on my 850 as I rebuilt it, and I can't compare it to the factory effort, but I'm more than happy with it. Some folks have reported that the rod ends wear after a few thousand miles, so regular oiling is a good idea

Some people say that a few turns tighter or looser will make a big difference. It's such a pain to do this, I just left mine where I set it and it did help with the low rpm vibration, but couldn't tell any difference from the original head steady at road rpms. Everyone's seems to vary. It probably has to do with what your iso clearances are and probably even the type of rubber donuts in them. My bike doesn't even seem different with different iso/frame clearances and I've tried from .01 to .025 where I have it now. There's probably too many variations to come to any conclusions.

Dave
69S

Thanks Dave and all.

Your original explanation and suggestions can at least get me started.
Although, to be honest, I think my current "by chance" spring setting is already 'good enough'; at least for the kind of riding I like to do.

So much fun riding this gem of a bike

Cheers, Aris