It looks the same as the original and yes the holes in the piston are ports for gas exchange which I also have in my bike. I also have the manual somewhere which is for the twinshock and early monos but still is very handy as the engines changed so little.
Steve
Hi Marcus I too have a DT175 which has lost compression. So I went on ebay and found RD Parts Shop and on this page http://search.stores.ebay.co.uk/THE-RD-PAR...1167487QQsofpZ0
Steve.
