My first rig: I have now fitted a modified Cozy sidecar to my Royal Enfield Interceptor and now thinking about improving the steering. The bike has a 24 degree frame neck and 106mm of trail, and as one might expect steering effort is high and very tiring on our mountain roads.
I am in Thailand, so by the time I import parts the cost doubles. Lack of yoke/leading links availability aside, I have little choice but to build this myself, and have the ability to do so. While not an expert by any means, I have been reading about reduced trail yokes vs leading link front ends and leaning towards the leading link solution. My mind is not closed to the yoke mod however, as I would also make the yokes wider to fit a 4 pot calliper on the wire wheel.
Any suggestions regarding design parameters? -
trail?? I see the 2" (50mm) number quoted and that is a lot less that RE at 106mm.
Shock rate on the leading link?? Bike is 210 Kg wet, sidecar 90 kg empty, and I am 76kg naked although I rarely ride that way.
Robert,
There is considerable variation in all the parameters you mentioned. If you can't find a person that has successfully done the modification, you will be in experimental mode. You might look at the leading links designed by Unit [I'm not sure they are still building] as they appear to have a bit of adjustability. In your own design you should consider adding opportunities for adjustment where ever you can and might be making a development unit before you make the final item.
These days world wide telephone conversations are possible and even cheap or free through some applications like WhatsApp. If you can arrange a call with Claude Stanley at Freedom Sidecars in Pennsylvania. The last phone number I have for him is [country code] 570-837-5120. He had a lot of experience with custom fabrication of leading links and he's very generous with his time.
Good Luck and please keep us in the loop here and please include pictures.
Al Olme
Quote from Al Olme on October 13, 2021, 8:58 amRobert,
There is considerable variation in all the parameters you mentioned. If you can't find a person that has successfully done the modification, you will be in experimental mode. You might look at the leading links designed by Unit [I'm not sure they are still building] as they appear to have a bit of adjustability. In your own design you should consider adding opportunities for adjustment where ever you can and might be making a development unit before you make the final item.
Al Olme
Unfortunately I am on my own here as far as building something that is proper.
A quick Google search did not turn up any basic design rules other than 2 inches of trail, and that had variances of up to +/- 1/2". From a fabrication point it seems straightforward enough, but as of yet, I know nothing about the engineering.
I am comfortable with motorcycle front end design and the effects of changing trail on performance street and race bikes. I know little to nothing about an optimal geometry for a rig. I am prepared to go through a couple of reiterations, but surely there are known design parameters?
Not sure that someone who is in the business of building leading link front ends would be willing to tell me how...............
Go to the watsonian sidecar sit, and look at the sidecar for sale. I know it’s on the left side but look at the lead on the sidecar compared to the front edge of the seat. A lot of lead( factory set up). And watch their video with no steering mod..Rudy
