Originally Posted by motolab
The previous poster was encouraging you to replace the jet needle as well as the emulsion tube (needle jet). To that I would add the slide guide and the slide, or else the emulsion tube won't last very long at all.
Well, it seems that my slide guide is indeed worn out:
Now my question is, it seems that for some reason Suzuki does not offer the slide guide as a replacement part - at least I could not find it in the carb diagrams - so I presume it is not sold separately - am I right? In this case, I would order the slide guide from KTM if anybody can confirm that the slide guide used on the 640LC4 (2001-2003) that has a BST40 carb as well, fits on the Suzuki DR650 stock carburetor. I know that the slides are slightly different (the KTM one has two vent holes, while the Suzuki has a single vent hole), but are the slide guides identical?
Also, for some reason my cover has a small area where the sealing surface is not flat:
I guess the gap - not visible in this photo - is around 0.3 millimeters. Otherwise the cap does not seem warped. My question is, is there any issue to be expected if i flatten out the whole sealing surface? This means the total height of the cover will be reduced by up to 0.5mm in order to achieve a flat sealing surface. Should I try this, or is a brand new cap strictly required in my case?