Pantah Chassis

Front suspension can be very harsh. Experimenting with different grade oils and spring rates is time consuming and expensive. Forks can be lowered by approx. 25mm through yokes to give better steering response. Yokes from the bevel twin range have been fitted, with packing shims, to speed up steering response. Complete 38mm front ends from bevel series have also been fitted. Fork legs and yokes can be difficult to polish up without exposing blow holes. Standard Marzocchi Strada rear shocks are over sprung and under damped. Alterations to give reasonable results are not easily done as the units have to be dismantled and the internal damping washers arrangement altered. Popular substitute for standard shocks are Koni Dial-a-Rides. Fontana’s have also been used. Spas mono shock conversion done on one machine with very good results. Rear swinging arm bearings in engine are notorious for wearing out. Regular checks are advised plus rotation of the pin. Lubrication nipple and needle roller conversions have been done, one in the swinging arm ends resulting in less work when changing bearings. Rear wheel adjuster blocks can corrode inside swinging arm. Greasing of blocks recommended. Outer clamps can break if over tightened. These are two different sizes with a thinner one being positioned next to the brake calliper mounting plate. Centre stand clearance affected with this modification. Rear, and front, spindle thread size is 16mm fine rate. Crash damage to frames in small accidents usually limited to steering stop plate lugs. Centre stand side lug can foul ground if bent. Stand can be altered by welding plates to feet to increase clearance. Stand springs can rust and break. Stainless springs available via Club, also rear brake pedal return spring, cable clutch arm return spring. Chrome on clip ons, gear lever, rear brake lever assembly is pathetic. Rechroming and stainless/rose joint conversion done on one machine.
Frame is strong in horizontal plane but tends to flex in vertical. Frame rigidity can be improved by welding gussets to all the engine mounting points and cross bracing behind the rear cylinder. Rigidity is further improved by welding triangular plates at the bottom cross tubes at the front of the frame to reinforce the steering head. Front end and rear wheel of a RGV 250 have been fitted by adapting the sprocket and making up spacers and fitting axles giving better tyre choice. Rear wheel from an F1 or Alazurra can be fitted. Poggipogiani air-valve top nuts have been fitted with double lip oil seals. Guzzi S3 handle bars can be fitted to raise riding position. Dymag wheels have been fitted. Fork dust covers were found to provide a lot of stiction to the forks. Solution is to remove them and use suitable fork gaiters (Norton Commando, MZ) for a substantial improvement.
Suspension Original Marzocchis very harsh on bumpy roads and started to leak after 35,000 kms. Replaced with Bitubo shocks with fully adjustable preload (threaded collar) and damping. More compliant but probably not worth the high cost. Front forks filled with 225cc of 10wt fork oil rather than 185cc as per handbook. Much improved damping. Works Performance gas shocks have been fitted with good results. They also list shocks for a number of old Ducatis on their website.