The primary is vented so there shouldnt be pressure in the primary.

 

I'll admit I'm not familiar with 2012 models.

 

All twincams vent through the transmission.

 

If that's how it's supposed to work, it doesn't work well. I've had to seal primary hole plugs in 2008 and 2009 models (modified to have forward controls ... so I assume that the plugs were part of the forward control kits) that were weeping fluid around the plugs.

 

Make sure your tranny vent tube isn't kinked.

 

I can vouch for one bike but not the other. I didn't do the forward control installs on either bike ... just trying to help friends out by fixing existing problems. But I did have the 2008 Dyna completely apart, so I'm fairly confident the vent line was good to go. Would the type of fluid used in the primary make a difference because of viscosity?

 

I'd say ATF would be the most likely to weep but my guess would be not using silicon sealent even though its not required. To many variables to speak to a specific situation without seeing first hand.

 

ATF is exactly what both were using. Good lesson learned. Thanks

 

Hope this helps

 

Oh that damn primary mid controls hole. I swapped out my cover and had the same issue.

If you bought the cover from the dealer have them change it for the right one without the hole. There is a cap that comes with forward controls to cover it but it is only cosmetic.

I had a friend of mine who is a machinist plugged it up from the back. He tapped the whole and closed it permanently. Then I popped in the cap. My advise would be find a mechanic or machine shop and have them close it permanently.

My switchback is very modded so if out have any questions don"t be shy to ask. It is currently all torn down for my large winter project.

Here are some picks of the blacked out engine, you can see the plug in my primary cover.