|Tech Tips by Randy Pozzi
|#4 CH 250 Performance Upgrades
Many of the posts for the Group have been talking about getting more power or speed from your Honda Elite Ch 250.
Several manufacturers have upgrade kits specially for the 50cc class which include bigger cylinder heads, full flow mufflers, roller weight modifications, performance belts and variator's.
While the smaller displacement scooters need the added performance upgrades to get them safely with the traffic flow, manufacturers have avoided the CH 250 seeing that its already able to cruise at 70+ miles per hour.
Based upon research and talks with mechanics, there are several upgrades easily made to your Honda Elite CH250 scooter which can provide added performance.
For Stock OEM Applications:
Re-Bore the Stock CV Carburetor: The Kehnin Constant Velocity carburetor is an excellent carburetor and is used on many performance motorcycles including Harley-Davidson.
Enlarge the plenum bore of the stock 26.8mm Kehnin carburetor to the comparable Mikuni 30mm for increased air flow.
Re-jet Carburetion: The stock Kehnin carburetor provides for a #115 main jet and #38 slow jet. Replace them with #118 main and #40 slow jet and enrich the fuel circuit by backing out the pilot screw to 2 and one-half from two turns out.
Exhaust Manifold Modification: File away the weld bead of the exhaust manifold where it bolts to the motor from 23mm to 27mm to allow exhaust gasses to exit unimpeded.
Adjust Roller Weights: Both the Honda Elite and Helix have the same 22.6 gram, 24x18mm roller weights. Decide what type of performance you want--For quick acceleration but reduced top speed, reduce the gram roller weights. For increased top speed at the expense of quick starts, increase the gram roller weights.
For Bolt-On Performance Applications:
Performance Variator's: Any of the Malossi, Polini or Betella Variator's designed for the Honda Foresight 250 reportedly will work as a bolt-on power boost.
Drive Pulley and Clutch Springs: Any of the Polini Drive Pulleys, Polini and Malossi high performance clutch springs for the Honda Foresight have reportedly added increased throttle response during tests.
Performance Belts; The Dayco and Malossi performance belts for the Honda Helix and the Malossi Honda Foresight 250 have proven to help with performance improvements.
Clutch Springs & Driven Pulley Springs: Performance Polini clutch springs and Betella driven pulley springs for the Honda Helix and Honda Foresight 250 will provide smooth acceleration without any hesitation especially in low end throttle acceleration.
Randy Pozzi (Rev. 07/2004)
and maintained by doug Elam