30HP is attainable out of a Honda CRF150R single motocross WATER COOLED engine. They're a multivalve thing. A bloke was running one of these in the Motolite class with the PCRA. Nobody could catch him. Interestingly, in that class, they put 150cc water cooled 4 strokes against 185cc air cooled 4 strokes, 100cc air cooled two strokes and 85cc water cooled two strokes. At first the 4 stroke boys still complained at how they couldn't possible match the two strokes. They wanted double the capacity of the smokers. Then within a couple of years the smokers couldn't catch the 4 strokes anymore.hawkwind wrote:DaveTop speed mag for a 2012 CBR 250R not RR my point was to show that even a 4 stroke with almost double the capacity is still behind the eight ball compaired to a 150 2 stroke. or even if we add in the RR it still proves that the 150cc 2 stroke is not very far behind the performance curve of the top dog 250 4 stroke ....its that model of 2 stroke that holds the world record in the 175 class at over 130 mphDont know where ya getting ya specs from. 26 HP LOL ya kidding me?
Chris..... please point me to any 150cc 4 stroke that was/is a production model and can still be purchased (new or second hand) that has exceptionally more performance than these 4 strokes? Again the point is to expose the vast power difference between 2 production models that represent the top of the performance ladder, its chalk and cheese.
Guys I admire that you want to race these small capacity 2 strokes it really does make racing afffordable and bang for buck you cannot beat a 2 stroke, I hope you all exceed in your dreams of a record Alas if I were to campain a 4 against a 2 in this class my hopes of a record would be just that ...a dream
cheers
gary
Even with that capacity advantage, the air cooled bikes have no chance of being anywhere near the front. This isn't speculation. This is years of actual race results with these engines against each other.