Currently reworking a '74 Yamaha TY250A and I'm going to need to replace the stock shocks. Traditional or nitrogen? Who makes good ones these days? Will an extra length change the handling much? Stock shocks measure 12-1/2" but I suspect that the springs have sagged. How about fork springs, firm or soft? I haven't ridden trials since Sammy had hair so I'm on a steep learning curve here but it sure is fun getting it sorted out.