Yeh, I know its not VMX, but they use the same engines. Here's some pics, with comments from Lyall on some of his engine wizardry:
![](http://api.ning.com/files/-KUL-sawsRWtUtIJgY5MWCs6u1jLALxElysbxie1IkTs*DPU3n-f9D8IJDatVWJ*YhGrJyjIoOBBpDVAZJizV648ibOAj3i2/LyallObrienMontyroadracers1st250Classic.jpg?width=640&height=411)
"First 250 Classic r/r built. 36bhp @ 8000rpm on alcohol. Built 4 of these in all"
![](http://api.ning.com/files/1HNjh45gvkl6KhdZpY3V7bg-1tVY7XhWXiyCMSjptVyMEEmK7Co7nF-HRS96NwsycLdd060iob-ftnuytcz9kkWKapRuvXQ-/LyallObrienMontyroadracersEarly350.jpg?width=640&height=425)
"Early development of 350 r/r. (De) stroked motor by 1mm, 347cc. Riders Craig Morris & Terry Morris. Won 3 Vic titles & 2- 2nd in national titles. Motor stock put out 38bhp @7000rpm at crank. Final development with pipe photo enclosed & six port cylinder & head work 52bhp @ 8200rpm at rear wheel on alcohol. 38mm Amal. Internal rotor electrics late model Montesa. All genuine montesa parts only used"
![](http://api.ning.com/files/Vz3BouZ6EYJXNfT6Qe*koDALEukWkLO4mbYjAk7NTcmgF*fFAImGRbUkVDuPFe0CLmba-T5Csq85axjNQweuLPnUgcdCpVtZ/LyallObrienMontyroadracersFinal250.jpg?width=640&height=425)
"Final development of 250 r/r. (Originally 250 Impala road bike) 26bhp @ 8000rpm at crank (std). Last of 4 built. 38bhp @ 8500rpm at rear wheel on alcohol. 36mm Amal. Approx 12 Vic state titles. 2 national titles. All std Montesa parts used. Bored flywheels to take 20mm crankpin from later model to take INA big end bearing. Since 1991 never had a blow up as the revs were never over 9000rpm"
Interesting info from a Monty tuning wizard!