You are right Mike, cost does have to be considered so I have set my budget at 400-500 quid tops.
For 450 quid I can get a set of ready made billet yokes from ebay. With no adjustability, hopefully replicating the std bike's geometry but who knows? Made primarily for the shiny chrome streetfighter crowd. This guy is just replicating his original design so perhaps we can say 100 quid for materials and 350 quid for his time and profit.
Would they be strong enough, who knows? They are probably fine for those folk that ride 50 mph upright between bike shows, bulldog bash, mayday run etc. How they would cope if you are wanging it around a corner, find a tractor in your path and have to make a quick direction change on a potholed Uk road, not so sure.
But is it really cheaper to use various Yamaha bits off ebay? Not from what I have seem: Gen 2 top yoke with risers 100 quid, lower yoke about the same, steering stem 50 quid for a stock one you have to get machined or 100 quid for a custom one. Plus getting it all fitted together. I reckon you are still in for 450 quid ish.
Also you still dont know if what you have created is strong enough. All of those bits designed for other bikes were not designed to work together so again, do we really know if they would cope in an emergency. I accept that most of us are just doing this mod for our own use and will take our own chances but I wouldnt recommend lending a modified bike to a mate or selling it without putting it back to stock.
The only way I can get adjustable yokes designed and built withing budget is to find someone that does that type of work as a hobby / sideline. Those sort of people are involved in racing and particularly in Supermono where there are few restrictions on engineering. I have a few contacts in racing and they are all pointing me to the same people. If I can get them interested enough to take the project on I reckon I can keep it within budget....I hope
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