Hemmings iso adjusters

I have Hemming's iso screw type adjusters. Does anybody know the size and thread of the tiny
allen set screws. Are they metric perhaps?

Onder, I don't know the thread size.

I have the Hemmings adjustors on my 850 and immediately after installing them I noticed that my ISOS would tighten up, they would rotate clockwise no matter how much I tightened the little set screws. In fact I tightened so much that I broke off the nylon tips.

This was about 10 years or so ago. I mentioned this to Heinz Kegler and he stated his opinion that the set screws were too small and not up to the job.

He then drilled out the threaded holes to make them larger and then tapped them with new threads for larger set screws(actually they are bolts).

He also felt that the screws were very likely to bear down directly on the course threads that the adjustor turns on to set the clearance and that this was the reason the nylon tips tore off and the little set screws did not have enough surface area to bite into to stay put.

And so on his lathe he milled off, making a flat area, just enough of that course thread for his new larger set bolts to bear down on. Problem solved.

Perfect, when they are set for clearance they stay set now. Just a thought and I have no idea if this problem has been worked over and made better with the newer Hemmings as mine are from the early days.

The story behind the adjustors is interesting. Brian Tyree of Albuquerque, New Mexico, was riding his Commando home from the Norton National in Torrey, Utah years ago when he conceived the idea of making and marketing threaded ISO adjustors for pre Mark3 Commandos.
When he got home he made up a set, applied for and received patent approval, and then visited England to discuss having Hemmings sell them. I was one of the very first customers because I knew Brian from him living here in Albuquerque with both Heinz Kegler and myself.

Brian Tyree did not foresee the Commando vibration acting as a tightening force on his adjustors, he felt that only a small set screw would hold them in place just fine. When I received my set from Hemmings I ran into the problem and Heinz took care of it for me.
I assumed, apparently wrongly, that Hemmings was aware of this and was selling them with larger set screws. I guess not. Maybe I was the only one who had that problem?

I am pretty sure of Brian's involvement as the original creator, yet it is just speculation on my part that Brain may not have been aware that the original set screw screw set up was too wimpy for the job. I am surprised to see them continuing to be sold without the beefing up of that area that Heinz fashioned for me.

Is the Hemmings and RGM adjustable isolastic two different products, the RGM sourced ones have a smallish grub screw also.

When I was diddling with them this afternoon I recalled your old post about modification on the lathe but
didnt remember opening up to a larger thread.
Both have lost the nylon tip. Well, not lost, just parted company from the screw. Mine are about 2 years
old got them straight from Mick. I see now that Andover offers them.
Mine tightened up. If the collar had a hex outer, you could easily loosen. If the little holes were bigger
it might take care of that problem.
Angela reads this list and so does Joe so maybe we will hear from them.
I want some extra screws as I thought maybe if I had three per collar they would be more secure.

Onder said:

I have Hemming's iso screw type adjusters. Does anybody know the size and thread of the tiny
allen set screws. Are they metric perhaps?

Click to expand...

Not sure what breed my ISO Adjusters are but the grub screw is definately METRIC in mine..

The set screw is 4mm in diameter with a 0.70mm pitch and 5mm long. It's a special soft tipped set screw. If you have trouble finding them McMaster-Carr sells them in a package of 5 p/n 93285A211
http://www.mcmaster.com/#93285a211/=shobqt

I hope this helps.

Thanks for that, McMasters is it then.

Thank you also.