Hello, just wondering if this is a good replacement for the primary cover O-ring. I have a '22 Road King. Thanks:

https://www.grainger.com/product/GRA...=true&opr=THKS

 

On a 22 I would recuse the factory gasket at time or to before replacing.

rk classic.

 

Do the new bikes use a true o-ring and not the flat style o-ring? This is what my 14 takes:

 

+1 I don't think I've ever changed mine. At 6 years and 60K miles now too.

 

OK, good to know about longevity. I'll just check the condition every fluid change. Thanks all.

 

That's is what my 2019 takes. I wouldnt mess with getting an aftermarket o ring.

 

you mean for derby cover. Like lp, have never changed mine once either.

 

I replace mine at every primary oil change.

 

Here's how it goes:

All Milwaukee 8 and last year Twin Cam baggers use that flat style o-ring. Those bikes are equipped with a 7.75" dia derby cover.

With the exception of the last model year baggers, all Twin Cams came with the 7.25" dia derby cover. Some of those derby covers have the gasket channel and use the flat o-ring (same p/n as the Milwaukee 8 version: 17369-06), while others use a full disk style gasket (HD p/n 25416-99C). If there is a hard and fast way of knowing if a Twin Cam came from the factory with the flat o-ring vs the full disk gasket, I don't know what it is.

Twin Cam outer primaries are compatible with either type gasket, so if you open yours up and find the flat gasket, but want to convert to the flat o-ring (and have a derby cover with the required gasket channel), you can. Or vice versa.

My $0.02 on that: AFAIK, the gasket on my '90 Electra Glide (the gasket channel on Shovels and Evos is in the outer primary) is still the same one that came from the factory, and I've never had a problem with leaks. That said, for the cost of a gasket, changing it is cheap insurance. The packaging from HD on the flat o-ring gasket says it is for "1k / 5k / 10k" service.