External Breathers and Catch Cans - The Only Reason to Buy

Comments · 253

• PK

  @pk-teia6249 · 3 years ago

  The other day I did a 15k service on my 2018 M8 Road King, and the air cleaner was full of oil. I've been riding since 1978, and back then we had 2 stroke motors. It was allways a debate what amount of oil you should dial in on your oil mixer, and it often was hit and miss. Now adays we have 4 stroke engines in our bikes, and I understand that Harley has to build engines that comply with the epa regulations. But still, our engines are not ment to be burning oil. They never has been, and never will be. Therefore I am going to install a catch can to avoid all that crankcase oil mist being routed into my aircleaner/combustion chamber.

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• TH

  @thejerseyj5479 · 2 years ago

  DK Customs has been putting out a bunch of videos on this subject and they have done a ton of research to confirm that venting the crankcase air helps your bike run cooler and with more power.

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• KR

  @krisf7208 · 1 year ago

  A catch can is a really good idea on newer cars that are direct injected. Helps keep valves cleaner. It's a serious problem, especially with turbo vehicles that are harmed by fuel system cleaning.

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• SY

  @syyenergy7 · 1 year ago

  I just installed an external breather after 36 years of not using one.  The excess oil problem usually likely comes from overfilling the oil.  In Florida, on really hot days, after a few hundred miles it's easy to slightly mis-judge how much oil you should have put in.  The oil will expand more than you think sometimes.

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• CH

  @Charger212 · 2 years ago (edited)

  I’ve been building engines for over 50 years only about a half dozen Harley’s but to me it’s an engine and I do them all. The reason I go with external breathers is your combustion charge is much better without oil and in some cases moisture which  I have seen many times. The only reason Harley doesn’t vent to the atmosphere anymore is because  of the EPA plain and simple. They mandated all gasoline motor vehicles to have a pcv in the late 60’s. Before that engines had a breather on the end of a pipe sticking out of the manifold. The EPA is the reason we have so much trouble with vehicles today, diesels, gasoline cars and Harley’s. Too lean and when you tune them they run better. Well that’s my 3 cents, sorry it was so long. Love your videos. Don’t know if you’ll get it since it’s a year old but what the hell I thought I’d try.

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• RY

  @ryan_riffs · 4 years ago

  Been workin as a bike tech on and off for 20 years and honestly don't see many catch cans in this realm but I did once own a twin turbo BMW and the aftermarket catch cans on that engine did a pretty amazing job at keeping the intake runners and valve stems clean over long periods of time.  That was a twin turbo engine though.

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• PH

  @ph1l-1 · 4 years ago

  I would put a catch can if the engine has direct injection as gas is directly sprayed into the cylinder. This can cause carbon build up on the intake ports and valves.  Port injection cleans the back of the valves each time the gas is sprayed.

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• TH

  @theokomulainen7549 · 3 years ago

  Precision engineering from Hardly

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• US

  @usmcvet0313 · 2 years ago (edited)

  I put one on my stock twin cam, along with the DK customs O2 sensor Vied's. I just wanted to cool the motor down, which it did. Runs great now, not melting my thighs in the summer. Made my own with flexible fuel line, hose clamps, and a pod filter. Routed it under the motor, pretty cheap.

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• PO

  @pogmothoin7164 · 3 years ago

  I made a catch can connected to a vented dipstick and external breather.  No pressure at all to the heads,  and all the moisture from the cold starts goes to catch can.

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• MO

  @Motorcyclemanbh62 · 3 years ago

  On my TC 103 i modified my SE stage 1 with a blowby bypass with a Filter not a catch can....I was getting a strong smell of burnt oil at operating temp when idling at stop lights....So i did that and put a Jagg oil cooler and it fixed the problem....No burnt oil smell and heating issues in the 100plus Cali heat anymore....

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• DI

  @dieseljuice3 · 1 year ago

  Thanks for the video, I'm not a mechanic, but did put a DK Catch Can on my 2012 Heritage. I think it looks cool under the stock air cleaner. I run Lucas Ethanol Treatment, and Lucas Fuel Treatment every fill up, so my top end should be clean anyway. Keep making your videos, thanks for all you do.

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