Rising Sun Cycles LLC   Racer's Parts in Racer's Time
RISING SUN CYCLES
HOME|CONTACT

Road Racing, OEM & Aftermarket Parts and Accessories

News and Important Announcements Racing Motorcycles
and Motors For Sale
Accessories
and Product Index
Tools Specials & Clearance BLOG

Honda Technical Information

Running in / Warming up / Position adjustment
RS125R / RS250R
 
Warming up of power jet carburetor (pwj) equipped vehicle
 
  The year 1998 and later RS125R and the year 1999 and later RS250R have carburetors equipped with power jets, which are designed to continuously inject fuel at engine speeds of 4000 rpm or less despite throttle opening. If engine speeds of 4000 rpm or less are often used or kept during warming up, fuel mixture will become very rich, causing repeated rich feeling or hesitation. Especially, in winter fuel mixture settings are designed to be rich, causing propensities toward rich feeling or hesitation.  
     
  Warming up  
 
1) After engine start up, engine speeds of 6000 rpm to 7000 rpm will be kept with constant throttle opening until coolant temperatures go up to 40C to 50C.
2) If coolant temperatures reach the specified level above, then the throttle is gradually opened until 10000 rpm is attained. After that, snapping is used to keep warming up and the fuel cock is turned off when coolant temperatures reach 55C. If coolant temperatures reach 60C to 65C or you feel sharp engine revving up, warming up has been completed.
3) To stop the engine, fully close the throttle. Do not turn off the kill switch while throttle is kept open.
 
   

 
Running in
 
  Running in plays an important play in determining your physical conditions or avoiding mechanical failures. New machine or those with some parts replaced with new ones must be run in.  
     
 
1) for running in mileage, see owners' manual.
Coolant temperatures: about 55C
Carburetor setting should not change from the best settings (lean setting must not be acceptable)
2) Running at as higher gears (5th or 6th) as possible using fully open throttles is the best. If engine speeds are going up beyond the set speed, full opening or closing of the throttle is used to control the engine speed.
Engine speed associated with down shifting should not be raised so higher. (engine braking rpm associated with down shifting should be gradually raised as well)
3) To stop the engine, fully close the throttle. Do not turn off the kill switch while throttle is kept open.
 
     
 
The reasons why running in is required

Running in means the work which makes moving parts to move smoothly without resistance. Running in must result in smoothness instead of looseness. Smoothness without looseness means that parts are able to move to intended positions accurately, speedily without any resistance, resulting in, when parts are assembled, the best performance.
Good running in practice will give parts prolonged life, providing constant performance for extended period of time.
For instance, if loads are applied to pistons at a stretch at the initial stage of running in, deformed pistons will result, which will reduce service life of the cylinder as well since already deformed pistons cause severe contacts partially at the extended travel kilometers. Also, the performance will be degraded as well.
Good running in practices will secure constant performance for periodic part replacement periods.
 
 

 
Position
 
  The RS, intended for sale to the public, does not provide the best riding positions to all the riders. So, the RS may not fit some riders with regard to extremities.
The point in determining positions is that riders can control his/her machine with ease. The most important things are machine holding by the lower half of the body and relaxed upper half of the body.
Integrity of lower half of the body becomes important in response to sudden skid during cornering. Also, relaxed upper half of the body is effective in turning or delicate brake control.
Seat height, seating position, or handle position should be changed to fit your body so as to ensure free upper half of the body and machine holding.
To hold the machine by the lower half of the body, ankles should be used to hold the machine, leading to integrity of the machine and the riders. Positions should be found which will give you aggressive machine control.