BRIDGESTONE GTR PISTONS

[reed]

Bridgestone GTR pistons.
When i pulled the cylinder's off on this engine the crown of the pistons were different!
This is the first engine i have seen with type of piston as you will see in the picture.
Thanks.
Steve.

[reed]

This piston is for Coxy i had a Triumph 650 come in this not running.
If you look at the piston you will see why!!
Thanks.
Steve.

[william anderson]

hi steve on this piston it looks as if someone has fly cut it to change the port timming , or get more from the ports , we use to do this in some of our motors that we raced , jet ski , an drag bikes , some times on the m x bikes , we also did this on the  early kawasaki kd , an kx 125 when we installed the skunk kits

[bsracer]

I had a set of SR175 pistons that were cut in a similar way. Old school way instead of porting the cylinder.

paul

[coxy]

ha. i was like that after Christmas. pistnbroke ! i will break it down for you Steve (ztnoo) slang again.
pissed here means drunk .
broke means out of money . so pistnbroke
but seriously i am glad that triumph piston  aint mine there not cheap .did it drop a valve?

[disc_valve]

The piston was cut away to change the exhaust port timing - the same effect as raising the top edge of the exhaust port, but without naving to cut the cylinder. With a chromed bore, there was always the risk that the chrome would start to peel if you cut into it. I believe that was a standard way of changing port timing on 175s, 200s and 350s.

If the piston had been "played with", it might be an idea to check teh disc valves, in case they had also been "trimmed" to change intake timing.

Graham

 

[reed]

Graham,
I have replaced the rotary valves just in case!
Thanks.
Steve.