I suggest that when many guys go about tuning motorcycle engines, they believe all the theories. My first racing motorcycle was like that. My mate Allan Greening had built it, and it almost killed him at Bathurst in 1958. It was a Triton with a 500cc short stroke motor which was made out of 650 parts with a 63mm stroke billet crank, in a Manx frame. It had a 4 speed close ratio box. When I got it, it had 4 inch megaphone exhausts from the 1954 T100 factory race kit. The first time I raced it, it crashed me at 100 MPH. It had been built with all the theories.
The biggest threat to my life was getting balked in corners. If I was not fast enough and my revs dropped, I had nothing to get me out of the corner. If I slipped the clutch, the bike would go sideways when the revs rose enough to get power again. The bike was like a very nasty dog - you might love it, but it would bite you without much provocation.
When I built my Seeley 850, I probably knew what I was doing. It does not matter much what motor you have you can usually make it work well, without spending a lot of money. Horsepower is not the be all and end all. When you race, there is always a pattern involved and a lot of variables to manage. The main variable is the type of circuit - different bikes suit different circuits. If you think about the variables involved, you find you have options. Changing only one variable often does not really help much. For tight circuits, tyre pressures and gearing might be better if they are lower - but that is not always the case. It depends on how much horsepower you have and at what revs.
In my situation, I have only ever raced my Seeley 850 on two circuits - Winton and Mount Gambier. Both circuits are similar - tight with no big sweeping bends. and not very long straights So for me, racing is easier. Nothing changes much.
If I wanted to race at Phillip Island, I would need to do a major rethink.
The biggest threat to my life was getting balked in corners. If I was not fast enough and my revs dropped, I had nothing to get me out of the corner. If I slipped the clutch, the bike would go sideways when the revs rose enough to get power again. The bike was like a very nasty dog - you might love it, but it would bite you without much provocation.
When I built my Seeley 850, I probably knew what I was doing. It does not matter much what motor you have you can usually make it work well, without spending a lot of money. Horsepower is not the be all and end all. When you race, there is always a pattern involved and a lot of variables to manage. The main variable is the type of circuit - different bikes suit different circuits. If you think about the variables involved, you find you have options. Changing only one variable often does not really help much. For tight circuits, tyre pressures and gearing might be better if they are lower - but that is not always the case. It depends on how much horsepower you have and at what revs.
In my situation, I have only ever raced my Seeley 850 on two circuits - Winton and Mount Gambier. Both circuits are similar - tight with no big sweeping bends. and not very long straights So for me, racing is easier. Nothing changes much.
If I wanted to race at Phillip Island, I would need to do a major rethink.
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