Here's for all including some notes.
Hello DogT ,
sorry for the somewhat late reply , but I guess there is no hurry .
First of all , I would like to say that , even if it is a fairly simple piece of work , it should be made with care , and attention to detail .
Do not underestimate the forces involved .
That is why I would recommend 4 – 5 mm steel for material .
If you use plain iron ,make it 6 mm thick .
The 2 holes for the bolts in the cylinder head should precision drilled , not sloppy , or oval , so that it will always be installed in exactly the same position .
When cutting the parts , alow some excess material in all directions , which can be removed when finished .
Best to make cardboard templates to try out for first , .
You see that I made a triangular cut out in the base plate for weight saving , but this is time consuming and not really nessecary .
A big round hole ( or no hole) is fine .
The 35° bend (ply) in the base plate must be square with the frame , not parallel with the holes .
If steel , you’ll need to get it red hot to bend .
I used a trough bolt , but if you want to keep the threads in the small cross tube , use a stud ( not a bolt! ) threaded deep and loctited .
Spacer (1) is 8 to 10 mm long , diameter 14-15 mm , and makes the Hsteady stand off the frame , and allow space for cables , etc ..
Spacer (2) is about 12 mm dia. and the length depends on the thickness of the vertical HS plate + PTFE sliders .
The length of spacer 2 dertermines the clearance .
Both spacers should be a close fit and cut straight to ensure parallellism .
The 2 washers should also be machined smooth and straight , not generic stamped washers ..
Mine are out of 4 mm stainless.
The 2 PTFE washers slide over spacer 2 .
Actually , I don’t think mine are PTFE , but Ertacetal or Delron , or something similar .
I cut them out of a large 1mm sheet I have , and replace them every 10000 kms or so .
the big hole in the HS is 24 mm and spacer 2 is 12mm , so there is a clearance of 6 mm all around , but I’m shure you could get away with less .
the engine doesn’t move all that much .
Welding :
Install all the parts on the bike , but without spacer 2 , so that the vertical plate is clamped solid between the washers .
This wil make shure that everything is in line .
Make shure that the 24 mm hole is concentric with the stud .
The bike should be standing vertical and on its wheels ! .
On the centre stand ( engine cradle type) the engine will move up in the frame = not good .
On the side stand the engine will move left = even worse .
The idea is to mimic riding geometry .
A pit stand is best .
Tack weld the 2 parts .
Remove the HS from the bike and finish the welds , remove excess material , polish , etc ...
The welding must be high quality ! .
If you are unshure about your welding , get a professional to do it .
You will see that I also have a polyurethane ring inside the big hole .
It is not really needed ;I only has a witness function to see how much , and in wich direction the engine moves .
Now , does it vibrate ?
Yes , but I set all my clearances ( isos + HS) at 0.10 mm , half the factory value .
It gives a very mild vibration over the entire rev range , but it does not bother me , and isn’t tiresome , even after a 500 mile day .
I gladly accept a little vibration for better steering and feedback .
If you prefer less vibration , it is easy to make longer spacers (nr 2) .
The 3rd hole in the cyl. head can be used for a spring .
If you have any more questions I’ll be happy to answer .
Best regards , and good luck .
Jan
(Ludwig)
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I must admit I have no idea how big the side load can be , so I made it pretty strong : the vertical piece is 5 mm (3/16") thick steel , the base plate 4 mm .SS end washers are 4 mm . the hole part is fully 3 dimensional .
I mesured the amplitude of the vibration at the head : about 2 mm , so a clearance of 3-4 mm between spacer and eye is enough .
To ensure perfect alignement , the 2 parts are tack welded in situ .
Lateral movement is controlled by the length of the spacer . I set it at 0.10 mm (.004") . I only use 2 bolts on the head . On bolt 3 is a spring preset at 20 kg (44lbs?) to take the weight off the front iso
http://www.britbike.com/forums/ubbthreads.php?ubb=showflat&Number=73352&page=1
