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</o:shapelayout></xml><![endif]--></head><body lang=EN-GB link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal>I’ll be removing my carbs soon in order to achieve clearance for raising (the front of) the engine. (Harmonic balancer installation).<o:p></o:p></p><p class=MsoNormal>So, it struck me that I may give my 3 HD6s another go. Swap them with the current setup.<o:p></o:p></p><p class=MsoNormal>Thinking it through and looking at the big box of bits, I recalled what a pain it is to get the nuts and two washers onto the bolts that hold on the air filters. I have French manufactured K&N lookalikes. The bolt starts inside the filter, goes through the carb and gets two washers and a nut. Very awkward to deal with those nuts and washers. PITA.<o:p></o:p></p><p class=MsoNormal>I thought that I might put in helicoils then I thought “Why not tap the holes?”<o:p></o:p></p><p class=MsoNormal>The holes on my HD6s are 11/32” or 8.8mm.<o:p></o:p></p><p class=MsoNormal>I am no engineer but it seems to me, from looking at tables on Google, that I could use a 25/64” drill bit and tap them out to 7/16”. I have both the drill and the tap but would like some expertise applied to the issue before I start drilling.<o:p></o:p></p><p class=MsoNormal>Any input would be much appreciated.<o:p></o:p></p><p class=MsoNormal>Thanks,<o:p></o:p></p><p class=MsoNormal>Simon<o:p></o:p></p></div></body></html>