1200 Twin Cam Questions

I bought a PC-5 used with a map spec for aftermarket exhaust like mine. I will eventually get it tweaked on a dyno but plugs are a good colour so I'm in no rush.

It's made a big difference. But for the expense of a new PC-5 with dyno, I'd probably go to Hilltop.
 
180cc ONLY in FD. BMW reduced the amount

They did indeed, but my understanding is that it was to prevent oil mist blowing out of the outer seal if it pressurises when warm. I wonder if it starves the pinion bearing so I still use the original 220ml in mine, if I get a bit of mist so what, I'll clean it off.

I use 85/140 GL5 Rock Oil in all my gearboxes and bevel drives, I think it has improved the gear changes!
 
They did indeed, but my understanding is that it was to prevent oil mist blowing out of the outer seal if it pressurises when warm. I wonder if it starves the pinion bearing so I still use the original 220ml in mine, if I get a bit of mist so what, I'll clean it off.

I use 85/140 GL5 Rock Oil in all my gearboxes and bevel drives, I think it has improved the gear changes!
I doubt it causes a problem with the pinion. The pinion bearing is a pretty rare failure except on the very early bikes which had the full amount of oil but had a smaller bearing. It's mainly the big inside bearing (wheel bearing) which fails and that doesn't use the FD oil. These fail because of the shit FD design and or jet washing with too much enthusiasm.
 
I used 220ml in my FD. The main wheel bearing was showing side play for at least 12 months before the seal eventually started to dribble oil. There was never an oil misting issue from the FD. The rebuilt unit will also be getting 220ml when it returns from Mikeyboy . Mike said all bearings were "ready" and simply replacing the wheel bearing would have been a false economy. The FD had done 50K miles, but has only had 220ml of oil for the last 15K.
 


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