68 series 1.5 with dual strombergs. The car has had small oval aftermarket air cleaners on it for as long as i can remember. This car has been in the family for 33 years-trying to get things right on it...the oil breather is routed to a long hose going under the car to the outside air. Im guessing it should be rerouted to one of the oval air filters somehow, just like it did when it had the original air cleaner box setup? Can someone explain what the oil breather does? Is it for emissions only? Does it matter which carb i hook it up to?

 

Originally the breather line went to a single fitting on the air filter snorkel vertical face plate..... feeding breather fumes to both Carburetors. This was P.C. to get fumes out of atmosphere. By having breather fumes being sent through engine combustion process then out the exhaust, the the final product was less harmful. The oil fumes going thru the carburetors gummed them up and force more frequent removal for cleaning and new seal kits... another good thing, right?? The 68 ZS needles and jets were fixed and could not be adjusted for wear. Poor idle and difficult to get thru Smog check... fortunately too old to smog now..

If you want to hook up carbs to breather, put a nylon "Y" fitting in the Breather Line, and run new smaller lines to both air filters (I found a reducing Y fitting on E-bay...5/8 to 3/8"), (Could have been Metric equivalents).

For tuning these carbs, although not cheap you can convert to adjustable needle or adjustable jet. Triumph forum has a DIY procedure for adjustable needle that is relatively inexpensive, if you have a lot of time on your hands and above average amount of shop tools. Simplest is the adjustable Jet from joecurto.com., approximately $105 each from memory.

Rgds
David