The 110a is what I got. It touches the clip there the fairing screws into the metal causing a slight bow in the plastic. This cause the lower fairing not to fit properly.Mobil 1-110A
Purolator PL14610
Bosch 3323
many others
You may have an earlier bike with the oil cooler which would decrease clearance.The 110a is what I got. It touches the clip there the fairing screws into the metal causing a slight bow in the plastic. This cause the lower fairing not to fit properly.
Apologies. It is a 1994. Yes it does have 28 amp alternator.You may have an earlier bike with the oil cooler which would decrease clearance.
I would be a good idea to put the year of your bike in your bike description so it shows in your signature.
I've been using the HF-303 filters on my 1991 with no clearance issues. Might be a good idea to avoid filters with the wrenching nut on the 'bottom' of the filter for early ST's.I wouldn't use the Supertech's any more, ever since Walmart changed suppliers (used to be Champion), they are very cheaply made now. There's better!
You could also try HiFlo Filtro, some of the best filters you can get. Short HF-204 (65mm), Medium HF-303 (73mm), Long HF-148) 85mm.
LIsting for the ST1100 is medium.
WIX makes the Napa, and these are also good filters. Bosch and Purolator the same (Bosch owns Purolator).
I bought one. Looks like a good fitMobil 1 M108 should fit.