WillBrown Internet - Ref:WP10*CT-Main-100902q20_NPhondaCDI -  Updated 2/9/10 © 2005-10.

The Fantic twinshock machines in standard form are perhaps the most competitive twinshock trials bike available, but can be improved to the extent that they become very usable in less difficult modern events, and along with very good spares back up, and reasonable purchase prices (in comparison to various Japanese alternatives!), makes them a very good choice for anyone wanting to take part in twinshock competitions.

 

Chassis:

 

1. Replacing the old style narrow rests and relocating the mounting point, is perhaps the first thing to do on any Fantic which still has the original rests fitted. On the 240 the rests need to be located further back and downwards as they are on the 200, while those on the 300 can be moved rearwards a little. We recommend Raptor Ti footrests, as these are top quality and can be easily transferred to next bike, which in the long term means they are cheaper than replacing shoddy alternatives on a regular basis.

2. Steering head angle is very relaxed on 240 and 300, and results in rather vague steering input, not entirely suitable for the type of conditions encountered in modern twinshock competitions. Steering head angles can be updated, providing more modern geometry, and fractures or damage to headstock gusset plates, can be repaired at the same time.

3. Swinging arm pivots are often badly worn on 240 and 300 machines, and to help with this Classictrial are able to offer replacement spindle complete with grease nipple to lubricate bearings, inclusive of a set of finish machined phosphor bronze bearings, which do not need to be line reamed to final size after fitting like those offered by some spares dealers.

4. Earlier front forks are fitted with dual seal arrangement, and modifying the slider to accept a single seal as the later type forks, will reduce stiction and improve fork action.

5. Steering head bearings are very often badly worn, and when fitting replacements it is a very good idea to drill and tap the headstock and fit a grease nipple, and a pump of grease every time the bike is used, will mean head bearings will last far longer.

6. Original Fantic chain tensioners never work that well, and parts are sometimes difficult to find. A simple threaded sleeve fitted to swinging arm will allow fitment of a Beta Rev 3 tensioner, which works better than OEM, and has easily available parts.

7. Air boxes are very often in poor condition, and it is crucially important that any leaks or cracks are properly repaired, and that connection hoses are in good condition. The 249cc motors will not run properly using a 212cc air box, as these restrict air flow, as intake ducts and carb connection hoses are too small.

8. The 240 benefits from having a 300 type seat fitted, as this reduces the seat height and makes the bike easier to ride in serious competition. The 300 seat is easy to fit but ideally requires mountings welded onto the 240 chassis behind the rearmost side-panel mounting hole.

9. If you can find a 300 front wheel with fully floating brake operating cam, this will provide much improved braking over the standard fixed cam Grimeca hubs fitted to 200 and 240. Alternatively fitting oversized linings, and having them machined to fit hub exactly will also result in much better braking.

 

Motors:

 

1. First thing to remember is that if any Fantic motor is badly worn, its going to need to be properly rebuilt before carrying out any other modifications or changes, and that rebuilding something that’s in very poor condition can be quite costly.

2. On a sound motor in good condition, attention to the exhaust and intake systems will improve the running very noticeably.

3. Exhaust front pipes should be free of dents and excessive carbon build up, and the 300 Professional front pipe benefits from being cut open and properly repacked, as does the rear silencer. Most after market replacement back boxes result in reduced power and torque, but will often work a little better with new packing material.

4. OEM carbs are generally going to be totally worn out, unless bike has had very little use from new, and if wear is evident on hard chrome plated slide then the carb body is going to be badly worn, and replacing various parts will make little or no difference to running. Classictrial OKO carb kits provide a sensible alternative to a new OEM part, and will provide increased top end power, and smoother running at lower rpm.

5. Clutch slip is often a problem on many Fantic’s, and if after replacement of friction/steel plates, clutch springs, and careful inspection of clutch drum, centre, and pressure plate, the clutch still occasionally slips, this can often be cured by simply adding an extra steel plate, which has the effect of increasing clutch spring pre-load.

6. Piston ring on piston port 212 motors must be changed quite often if bike is used on a regular basis in serious competition, as reduced compression caused by a worn ring will limit the power output very noticeably.

7. All Fantic motors will run very happily on 70:1 oil fuel mix, using a good quality fully synthetic 2 stroke oil, and this will reduce carbon build up, and extend the intervals between cleaning out exhaust systems (nonsense propounded on the net about oil/fuel ratios, and synthetic oils, seems to have originated from a test carried out by Gordon Jennings in the 1970s!).

8. Motorcycle specific light gear oil is a good choice for gearbox lubrication, although automatic transmission fluid may sometimes improve clutch action a little (ATF is not a good idea for 240’s with worn kickstart spur gear, though).

9. Finally the cause of detonation on most early model 300 Professionals, is due to lack of exhaust blow down time, which can result in spontaneous combustion of incoming charge, through contact with the poorly scavenged exhaust end gases still present in cylinder. This problem can be rectified by Classictrial, and will result in much improved running.

 

If you are interested in having any of the above modifications carried out then please feel free to contact us, but we are not able to disclose specific information relating to engine, suspension, settings and geometry changes.

Fantic GRP fuel tank

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240 Fantic modified by Classictrial

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Fantic Trials tech

* Finally please remember that all of the above information is provided on the strict proviso that any modifications or changes not carried out specifically by Classictrial, are not guaranteed or warranteed in any way, and are entirely the responsibility of the individual carrying them out, and that Classictrial are not responsible in any circumstances for damage or injury that may occur as a result of poor workmanship *