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Unfortunately I had had a delay with my performance up grades due to major trauma motorcycle accident in Austria however have my heads near completed ported and engine stripped.

I am extremely interested with the head porting information and beliefs and I from the experts who have shared and printed books who have performance prof records I must admit I more trust them than others who hide and some who have disappeared with many peoples funds after shutting shop .....and one of the operators I was told it’s the second time so.... trust is also something I see as very important as well as sharing the mathematics and evidence.

I am looking at engine performance improvements with torque and acceleration as a major focus as I ride on windy mountain roads and even two up not on 4 mile salt flats so maximum CFM is less than ideal based on the expert head porting and performance books and posts I have read.

From what I have read the area with the lowest CFM in your engine is around the valve seat curtain area so if that is the lowest CFM why do most seem to believe the ports need enlarging is more important? I have made a choice after researching information in books and mathematics to go down David Vizards PolyQuad head design and increase 1 x inlet and exhaust valve in each cylinder and modify the port sizes to enhance flow through the larger inlet valves while matching in size and flow size 77% inlet valve sizing in which the standard ports show up as around 30% too large.....

Now the interesting thing I have found is the 44mm throttle bodies off a Street Triple and standard street triple manifolds outlet which are tapered for increased velocity design are slightly higher than the near recommended 77% inlet valve port sizing and more like 83% so I made adapter plates in which taper and match the street triple manifolds to the new reshaped Bonneville head ports and have a consistent taper from the 65mm opening velocity stacks on the inlet all the way to just before the valves in which the ports open to increase the port area slow down the air fuel mixture speed to pass the most restricted CFM area of the motor which is the valve seat curtain area.

This increases the velocity and forces the inlet fuel air mixture into the combustion chamber in a swirl high atomised high velocity ratio yet allowing time for the fuel are mixture to travel around the valve stem and valve seats increasing the amount of highly atomised fuel air ratio into the combustion chamber.

I look forward to going the next steps forward when I am back on my feet hopefully in early 2020 however I would recommend all to research the available information and David Vizard has many records and books with valuable information on the head porting and engine performance areas as well as another fellow last name Bell on the topic.
PS: Engine UpGrade Specs to implement with above head works

Aria 11:1 pistons
44mm TB Street Triple with velocity stacks and manifolds
70mm Pod air filters
2 into 1 TEC exhaust with larger 50mm customer reverse cone muffler
Power Commander with AutoTune / O2 sensor
Webcams 813c cam grind
 

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Hi Greg, sorry to hear about your bad luck being involved in a serious accident. but glad to hear you are on the mend (y)

good luck with the motor build, i'm looking forward to seeing the results.
 

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Hi Mike,

Thank you for the reply and wishes in which yes getting better every day and hope to be walking without crutches in early 2020. I visited two of my two friends who were also involved in accident and still in hospital yesterday which was great as 3 bikes with 5 people were injured which a tractor towing a sealed roof trailer carrying 6 cows crossed our side of road, jack knifed and rolled across the complete road so we had no escape.

As soo as I get myself back on my feet I will push ahead with the performance mods and inform you of my findings however due to injuries suspect may take a while.

Mime wishing you and your family a very Merry Christmas and a fantastic New Year and all the best in 2020!
 

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Glad to hear you still have a positive attitude mate. And hoping your friends make a full recovery also..... Sounds like a pretty horrendous accident

Thanks Greg, wishing you and your family a merry Christmas and a very happy New year also. Take it steady and don't over do it mate
 
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