Mikuni carb conversion: where do you run oil tank vent line?

I converted my 73 850 from two worn out Amals to a single Mikuni. And at least for my bike, the difference was amazing. Starts on first kick and settles down to a nice idle. Accelerates nicely.

For those that have done this conversion, what did you do with the vent line that runs from the top of the oil tank down to the bottom of the old air filter plate? Fab up a drip can?

I’d also like to see some pictures of your installations to see how you ran the main and the reserve fuel lines to the T. I wanted filters on both lines so my lines hang down below the carb. Looks OK, but I’m sure someone more ingenious sent me came up with a neater solution. Thanks!

I should have done a little more searching on this forum before posting. I found plenty of threads about where to run the vent line!

I run both fuel lines down just a bit lower than float bowl then “T” up and into carb , once a year (end of season ) I drain lines ,carb and tank , I leave tank (FB) bone dry through off season .... no filters , never had an issue with this method in 20 yrs

Kurt V said:

I should have done a little more searching on this forum before posting. I found plenty of threads about where to run the vent line!

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And what have you decided to do with it? Those of us with aftermarket air filters, even with dual Amals, face the same issue.

Like many of the posters I put a translucent catch bottle in the front of my 73 850s battery tray. There was just enough room to wedge it in front of the battery. I noticed a huge drop in oil accumulation in the catch bottle after installing an inline reed vale from Mike's XS on my crankcase to oil tank line. I also noticed less oil mist using a Mity-mite brake booster check valve. Not quite as effective as the Mike's unit, but pretty darn good for under $5.00 I went with the Mike's valve after years of using the Mity-mite mostly because it looked cooler.