These two small after-market Viton 75 O rings sit alongside the diaphragm. 

If you are removing the diaphragm cover on your carb to replace the diaphragm or whatever, best to replace these little O rings to save having to later if the cover leaks!

To help get a good seal, make sure all corrosion etc is cleaned off the cover before refitting, I rub the cover on a sheet of fine wet & dry paper on a dead flat surface to give it the best possible chance.

Carburettor diaphragm - fits all TTR models including the Raid

Genuine Yamaha part. 

If you also need the two small O rings that sit alongside the diaphragm then we have some after-market Viton 75 ones in the shop.

To help get a good seal, make sure all corrosion etc is cleaned off the diaphragm cover before refitting. I rub the cover on a sheet of fine wet & dry paper on a dead flat surface to give it the best possible chance.