J
Jack Klarich
Guest
You could use a set up like this with a filter or a catch can
Crankcase Breathers
- Thread starter RJMFXDC
- Start date
You could use a set up like this with a filter or a catch can
dolt
Well-Known Member
Venting to the atmosphere will minimize carbon build up as has been pointed out. You didn't mention if you are still running the OEM air filter and backing plate. If you are, you have some work to do.
If you have not upgraded to the SE Stage I A/C, you will need one of the SE kits depending on the T/B size; IIRC, the Dynas are equipped with a 50mm T/B but not sure. There are two kits, PN 29515-08 for the 58mm T/B and PN 29260-08 for the 50mm T/B. You will need to drill and tap the backing plate for barbed fittings for hoses to route the crank case ventilation away from the T/B to an external exit. You will also need to block off the internal breather passages in the backing plate.
As others have pointed out, there are a variety of ways to route the hoses to an external exit but most use a "T" fitting to connect the two breather hosed behind the air cleaner housing and route a single hose to a catch can or an external exit.
On one bike, I made a catch can from PVC pipe and filled it with the same mesh that is used in the cylinder head breathers. The crank case mist is vented to this can and the "wet" stuff collects on the mesh allowing the crankcase pressure to vent out of the can to a single hose that is routed between the cylinders and out to the same location as the transmission vent. A small in line fuel filter for lawn mowers is plugged into the end of the vent hose at the exit. I have never seen a drip from that system and have never drained any fluid from the catch can.
On another bike I simply routed the vent hoses to a Doherty in line filter also filled with the same mesh with no exiting hose. If ring seal on a motor is not good, there can be some fumes exiting from the filter and, in some cases, there will be some dripping. I have never had that problem but, like I said, that will depend on the condition of the motor and ring seal.
Dolt, Thanks for the pics, they help. I am running stock A/C, what concerned me was pics I saw of the top of a set of piston that were nasty after 9000 miles. I am not sure if that owner was running stock gear or Stage 1 A/C. That is why I was asking if the stock system was inadequate or is rerouting SOP for the late model twin cam motors. Thanks for all the info.
Thanks for the pic's Don, I had it visualized in my head (which is a scary thought) but it's always nice to see pictures.
dolt
Well-Known Member
Sorry about the poor quality of the first picture with the home made PVC catch can; so dark you can't really see anything. However same basic connections to the can as the second picture but what you can't see is a 90* fitting coming out of the top of the PVC can that connects to the smaller 5/16" vent line that drops down between the motor case and the primary where the trans vent is located.
The picture you posted is way OTT for a guy like me; function before form is more my style but it is a very good looking and tidy setup.
The picture you posted is way OTT for a guy like me; function before form is more my style but it is a very good looking and tidy setup.
J
Jack Klarich
Guest
Down and under the frame
Thanks Jack. The kits I found on ebay did not have the extended line. They terminated at the filter.
I have the Big Sucker and did exactly like the one in Dolt's first picture. used the same bolts and plugged the small holes in the front of the backing plate that would normally allow the blow by into the intake with JB Weld. Tee'd the hoses and routed down between the primary toward the back. No catch can or filter. IMO a filter is useless and requires maintenance and may as well dump it to the ground. Catch cans are expensive. Just be sure when tie wrapping your hose to not do it to tightly......Ask me how I know? That dipstick sure flies a long way. High too!