Yamaha 701/760 Freestyle/Freeride porting templates

yamanube

This Is The Way
Staff member
Location
Mandalor
Sorry guys, I have been busy with work and am currently out of stock on these. I am doing what I can to be ready to ship after the new year.
 
Location
Spain
Hola

Sé que este post estuvo en espera por mucho tiempo, pero lo encontré y es súper interesante.

He descargado el YAMANUBEYAMAHAPORTINGTEMPLATE y al comprobar las medidas el ancho del puerto de escape me da 62,1 mm.

Si el diámetro del cilindro es de 81 mm, el ancho máximo sería del 70%, que es de 56,7 mm.

¿Qué ancho tiene el puerto de escape en la plantilla?

Gracias
 
Location
Spain
Hola

Sé que este post estuvo en espera por mucho tiempo, pero lo encontré y es súper interesante.

He descargado el YAMANUBEYAMAHAPORTINGTEMPLATE y al comprobar las medidas el ancho del puerto de escape me da 62,1 mm.

Si el diámetro del cilindro es de 81 mm, el ancho máximo sería del 70%, que es de 56,7 mm.

¿Qué ancho tiene el puerto de escape en la plantilla?

gracias
Hello

I know this post has been on hold for a long time, but I found it and it's super interesting.

I have downloaded the YAMANUBEYAMAHAPORTINGTEMPLATE and when checking the measurements the width of the exhaust port gives me 62.1mm

If the diameter of the cylinder is 81mm, the maximum width would be 70%, which is 56.7 mm.

How wide is the exhaust port in the template?

Thank you
 
Location
dfw
No customer ever asked how long it will last with the port so wide. Since you are a thinking man, cut the port under 70% wide and raise it a little. This will make the same power with much longer piston/ring life. Throttle response may be a little slower.
 

yamanube

This Is The Way
Staff member
Location
Mandalor
Hello

I know this post has been on hold for a long time, but I found it and it's super interesting.

I have downloaded the YAMANUBEYAMAHAPORTINGTEMPLATE and when checking the measurements the width of the exhaust port gives me 62.1mm

If the diameter of the cylinder is 81mm, the maximum width would be 70%, which is 56.7 mm.

How wide is the exhaust port in the template?

Thank you
It depends a bit on what your bore size is but the port width is measured across the chord. These are CAD drafted and designed, I'd have to look back at my drawings but I think I am about 68% bore width at 81mm bore.
 
Location
Spain
It depends a bit on what your bore size is but the port width is measured across the chord. These are CAD drafted and designed, I'd have to look back at my drawings but I think I am about 68% bore width at 81mm bore.
Hello

I put an image of your template and taking the measurements in design program gives me 62.1mm.

If the diameter of the cylinder is 81 mm and the maximum width would be 70%, it gives me 56.7mm.

My doubt is that there is much difference between the two measures.

Thank you and best regards
 

Attachments

  • Template_measures.JPG
    Template_measures.JPG
    67.3 KB · Views: 35
Location
Spain
Hello

A picture is worth a thousand words

I was misunderstanding, I thought the 56.7, had to be the perimeter of the exhaust port, not the straight distance.

Thank you and best regards ;)
 
Pro Tip, or really amateur hack tip....I've used the same template for a variety of different bore sizes and stroke/port timing combos, just mark a line where I want the top edge and two sides to be and slide the template up down and side to side to mark that part of the port.

A Pro would probably do a more specific shape, the template is pretty conservative with big round corners and even more so if using it on a smaller bore.

But....we're not pros. So this works pretty well.
 
Top Bottom