Hello all,

I have a RX 135 running a ported goetze bore. The porting was done following up on the measurements of the original yamaha bore, perhaps .2mm give or take. This goetze bore is running on number 3[boring] and I have slightly flattened the piston top. [ This was done by my mech and on examination prior installation resembled a polished spot on the top which is slightly flat as compared to the normal piston]

I am also running a 26 mm carb from the stock 22 mm [ tuned where necessary] and 17 at the front sproket, 34 at the rear.

I have a 5 speed gear box

Now the question is I have the old type silencer and not the cat con one, and when I use the full insert the bike seems muted at the higher end while the torque is satisfactory. When i insert a chopped insert[ cut at about 15 cm from the holder ] the top end is good while the torque seems to be lost.

My mech is suggesting that I put in a RD 350 muffler insert, his view is that since one cylinder of the RD was about 175 cc, that my bike with the current set up would be compatible with a single RD 350 insert.

Has anyone done so ? inserting a RD 350 muffler insert into the RX 135 ? and has there been any difference apart from noise?