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

Function of carburetor parts
RS125R / RS250R
 
 
Basic functions of each parts
   
 
Jet needle
 
  Application of jet needle depends on which carburetor you are using, So please use appropriate jet needle for your carburetor.
Jet needles in Fig(1) and (2) has different length and tapered angles.
Using in appropriate jet needles will cause trouble.
 
   
     
 
Comparing taper angle α1 α2 α3
(1) 12/34(33)66/2351/1159 124' 239' 115'
(2) R12N(M)-1157D 124' 315' 115'
 
     
 
Comparing length mm A B C D
(1) 12/34(33)66/2351/1159 66 58.9 46.9 30.3
(2) R12N(M)-1157D 65 56.9 46.9 32.8
 
  (1) for carburetor with PWJ
(2) for PJ short carburetor (Unleaded fuel)
 
     
  The difference between 34 (standard) needle and 33 (option) needle for power jet carburetors is that the 33 needle is 0.5mm shorter at the raise of tapers than the 34 needle. That is, the 33 (option) is 0.5 step richer than the 34 (standard) if comparison is made in the same step.
Likewise, in the case of PJ carburetor without power jets, the M (option) is 0.5 step richer than the N (standard)