SP125 Limited  
  22 Walker Wood,  Baildon,  Shipley,  West Yorkshire,  BD17 5BE,  England  
  Telephone 01274 583231      steve@sp125racing.com      Mobile 07738 626165  
       
  www.sp125racing.com  
       
  Ignition Curve Changer  
     
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  Ignition Curve Changer  
     
     
  This is a great little add on for the RS125 & RS250 Honda, plus the TZ125 & TZ250 Yamaha.  
           
  The problem with the ‘safe’ standard ECU CDI ignition, is that if you advance the static timing to improve the mid-range,  
  then the engine 'brick walls' at maximum rpm due to being over advanced.  
           
  So the Ignition Curve Changer, which is simple & easy to fit, gets around the problems of the 'safe standard ECU CDI.  
           
  Basics        
           
  The Curve Changer unit is designed to work in conjunction with the existing standard CDI.  
  The unit forces a programmed delay into the pick-up timing.   
  As the RPM increases the delay has a greater effect on the ignition retard  
     
  In plain English, what this does is, it allows you to advance the static timing of your ignition and the Curve Changer  
  then retards the ignition at maximum rpm.  This gives you vastly increased mid-range power, without then sacrificing  
  any maximum power and over-rev.  It actually also improves over rev!  
     
  Without doubt, this is one of the cheapest and best performance add-ons you can fit to your machine.  
           
  In Stock now        
           
  RS125 Honda & TZ125 Yamaha  :  £225.00 + VAT  
           
  RS250 Honda & TZ250 Yamaha  :  £225.00 + VAT  
     
  Exports of all parts supplied to outside EC Countries are exempt from UK VAT  
  Exports to EC Countries are exempt from VAT if a valid VAT registration number is supplied  
           
 
 
   
         
             
  Installation Procedure - RS125 Honda        
           
  Remove the Static Timing Cover - On the right hand side of the engine  
  Advance the Static Timing to Maximum Advance & replace the Timing Cover  
  Locate the 16 way connector on the wiring harness, that is plugged into the CDI and disconnect.  
  Ease the outer sleeving back as far as possible (75mm), you may need to carefully cut the sleeving to access the wires.  
         
  With the 16 way connector facing away from you and the black wire to the left hand side :  
  To fit correctly you must find the 2 wires that connect to the Pulse Generator Assy 30300-NX4-003  
  Locate the White wire with Blue Stripe  -  next to the Black wire  
  Locate the White wire with Yellow Stripe  -  opposite end to the black wire  
         
  Gently remove enough insulation from those two wires, 40mm back from the 16 way connector.  
  Solder the Curve Changer Blue wire to the White wire with Blue Stripe in the wire harness.  
  Solder the Curve Changer Yellow wire to the White wire with Yellow Stripe in the wire harness.  
         
  Tape the joints with Insulation tape, ease back the outer sleeving on the wire harness and plug in the Curve Changer.  
         
  Remember to allow for carburettor jetting changes due to the extra power now available  
     
  125cc Handy Tip      
  To gain extra power from the BPS Curve Changer, you can obtain more static advance by extending the timing  
  adjuster slot & grinding off part of the Base Holder of the Pulse Generator      
  You will need to remove the main clutch cover to do this, bit it is a simple job.      
             
     
             
  Installation Procedure - RS250 Honda        
           
  Remove the Static Timing Cover  
  Advance the Static Timing to 8 degrees Advance & replace the Timing Cover  
  Locate the 16 way connector on the wiring harness, that is plugged into the CDI and disconnect.  
  Ease the outer sleeving back as far as possible (75mm), you may need to carefully cut the sleeving to access the wires.  
         
  Locate the White / Yellow stripe wire  
  Locate the White / Blue stripe wire  
  Locate the Green / Blue stripe wire  
         
  Gently remove enough insulation from those two wires, 40mm back from the 16 way connector.  
  Solder the Curve Changer Yellow1 wire to the White / Yellow stripe wire in the wire harness.  
  Solder the Curve Changer Yellow2 wire to the White / Blue stripe wire in the wire harness.  
  Solder the Curve Changer Blue wire to the Green / Blue stripe wire in the wire harness.  
         
  Tape the joints with Insulation tape, ease back the outer sleeving on the wire harness and plug in the Curve Changer.  
         
  Remember to allow for carburettor jetting changes due to the extra power now available  
     
  250cc Handy Tip      
  Best results found for AvGas Leaded Fuel:  
  8 degrees Ignition Advance  
  10.8cc Cylinder Head Volume with 0.7mm Squish.      
             
     
           
  Go to:    RS125 - 16 settings Ignition Curve Changer   
           
  Go to:    RS250 - 16 settings Ignition Curve Changer   
           
           
  CALL STEVE PATRICKSON  
  01274 583231  or  07738 626165  
  OR SEND YOUR E-MAIL TO  
  steve@sp125racing.com  
       
           
  Return To sp125racing.com Homepage  
           
           
 
 
 
           
     
  SP125 Limited Disclaimer  
           
  Honda, HRC and all other parts supplied by the SP125 Limited are not guaranteed when used in competition events.  
  As such, it is a condition of our making all parts available that it is solely the decision of each individual, rider, team member or   
  team whether they choose to use any part supplied and in doing so, absolve the manufacturer and SP125 Limited of any or all   
  such claims, including damage to equipment and/or injury to personnel irrespective of how caused.  
           
  All parts remain property of SP125 Limited until paid for in full.  
           
  All 'special order' parts, that are ordered specially under the instruction of the customer, are non returnable and non refundable.