Jeff Henise
Highwayman Bikes

72 TD3 dyno video

 

250gp. two stroke hp chart from many sources and is my best guess and can change without notice.

year model claimed crank est crank hp measured crank measured true rear wheel hp dynojet style hp
      (true x 1.1)   (crank x .9) (true x 1.15)
1959/1960 yds1r,  air cooled ??        
1962 td1,  air cooled ??        
1963 td1a,  air cooled ??        
1965 td1b,  air cooled 35hp (from someone's memory of Yamaha's claim)        
1967 td1c,  air cooled ??        
1969 td2,  air cooled 44hp (from Yamaha)        
1971 td2b,  air cooled 47hp (from Yamaha)        
1972 td3,  air cooled 49hp (from Yamaha)     40 measured with stock expansion chambers 46ish djhp
1973 ta250 (td3 engine, tz250 frame) 49hp (from Yamaha)     40 measured with stock expansion chambers 46ish djhp
1973 tz250a, watercooled 51hp (from Yamaha)     est 43  
1976 tz250c, monoshock 52-53hp (from Yamaha)     est 44-45  
             
1977 tz250d, stock 52-53hp (from Yamaha)     est 44-45  
1977 Morbidelli
rotary valve, parallel twin
rider:
    72 measured @ output shaft by Morbidelli estimated 65 true rear wheel hp 75ish djhp
             
1978 tz250e, stock 53hp (from Yamaha)     estimated 45 true rear wheel hp 52ish djhp
1978 tz250e mod, world class
rider:
    66 measured @ output shaft by Morbidelli estimated 59 true rear wheel hp 68ish djhp
1978 Morbidelli
rotary valve, parallel twin
rider:
    72 measured @ output shaft by Morbidelli estimated 65 true rear wheel hp 75ish djhp
             
1979 tz250f, stock 53hp (from Yamaha)     estimated 45 true rear wheel hp 45ish djhp
1979 Morbidelli
rotary valve, parallel twin
rider: Graziano Rossi
    72 measured @ output shaft by Morbidelli estimated 65 true rear wheel hp 75ish djhp
             
1980 tz250g, stock 55hp (from Yamaha)     estimated 46-47 true rear wheel hp 54ish djhp
             
1981 tz250h, stock 57hp (from Yamaha)     estimated 48-49 true rear wheel hp 56ish djhp
             
1982 tz250j, stock 57hp (from Yamaha)     estimated 48-49 true rear wheel hp 56ish djhp
             
1990 tz250A, 3TC, stock ? ? ? ?  
1990 tz250A, 3TC, many mods   est 75-76   66 measured true rear wheel (many mods) 76ish djhp
             
1991 tz250b, 3YL, monoshock          
1992 tz250, 4DP1, monoshock          
1993 tz250, 4DP2, monoshock          
1994 tz250F, monoshock          
1995 tz250G, monoshock          
1996 tz250H, monoshock          
1997 tz250J, monoshock          
1998 tz250K, monoshock          
1999 tz250L, monoshock          
             
2000 tz250M, 5KE, monoshock          
2001 tz250N, 5KE, monoshock          
2002 tz250O, 5KE, monoshock          
2002-2009 tz250P, monoshock          
             
late v type tz250, stock   est 72-73   66 measured true rear wheel (stock engine) 76ish djhp
late v type tz250, USA mod engine   est 82-83   74-75 measured true rear wheel (modified engine) 86ish djhp
rotary valve twin type 250   est 88-89   80 measured true rear wheel 92ish djhp

 

 

Some claimed hp from information from http://www.tz350.net/tz250page.htm