South Africa's First and Only 2-stroke Forum

After so long this motor are almost done.... Damn this thing gave me a headache and lots of stress...

Thanks Stephen for understanding.... I really could not asked for someone else, all the excuses and the little nature problem also... Glad that's over...

Here is some porting pics, will also put the complete motor pic up, once its assembled....

This thing is going to haul the mail, let me tell you that.....

First of all, a stock CR500 with stock porting and matched exhaust for peak power at 7500rpm is about 135 BMEP.... (google bmep if you don't know what it is)

The newly ported motor should be 168BMEP making peak HP at 8000rpm (depending on the pipe he will use)... Its not going to be worth porting this thing to making more power higher.....

This mean that we should have a power increase off about 20% (again depending the pipe carb etc) The calculations on based on the IDEAL pipe and carb size....

A stock CR500 made 58HP with a ton of torque and a very broad curve.... With the bolt ons, carb, pipe we should see AT LEAST a gain of 11.6HP...

SO we should hit 70HP easily... Some would say is that all.... Remember this will be a very broad curve with heaps of torque everywhere, So you don't need a lot of peak power.... Main thing is, its going into a 100kg bike, squuzing PEAK HP out of this motor should not be to hard, If the raptors can make 86HP, the CR will easily make 100hp, BUT we want a broad curve and keep the motor reliable....

As far as I know these 80hp raptors only run once a year...... ASK ATV Drag Racer...

I am confident that we will make 75HP realisticly with everything we've got and maintain a very broad curve..... High hopes for 80HP with all the extra bolt ons...

Exhausts Port stock, unmatched with exh manifold....




Transfers stock... Should be squared...




Intake Stock....


Intake is massive, so there is not a lot that can be done.....


Transfer updrafts casting flaws cleaned up...






Honda's way of lowering the compression... This port is much higher then stock, so those grooves were longer then in the pic, After about 2 bores they clean up....


Exhaust matched to manifold and in process of polish....


One needs to make all the lines straight with the manifold, or the manifold straight with the exhport lines, but in this case the manifold can't be changed because then the pipe won't fit, and the exhaust port floor can't be lower, same with the roof, or not much, otherwise you cut into the water jacket.... So this is the best you can do....

Those are not grooves, its the polish stone's marks....


Last but not least, NO JOB to big or to small!!!!!!!!!!!!!!! I build them ALL!!!!

Dis nice gedoen B! Natuurlik

THANKS B,

WOW!!!!!!!!!!
THIS IS PROOF THAT ALL GOOD THINGS TAKE TIME!!!
I'M LOST FOR WORDS MAN......I CAN'T WAIT TOO RIDE ME SCOOT

CHEERS

S

net wow

Eks oortuig jy sal haapy wees, net jammer jyt die bike so lank terug gery.... Sodat jy n goeie vergelyking kon doen, maar eks oortuig jy sal dit dadelik agter kom............