Oil cooler help.
Ultimate HDF Member
Joined: Aug 2007
Posts: 9,486
Likes: 4
From: Hico, TX (once home to Billy the Kid)
Not for cooling lines.
Cruiser
Joined: Aug 2007
Posts: 102
Likes: 0
From: Tucson, AZ
Oil Filter
I have questioned the plugs myself and was told they can't be used. Still not clear what they are.
Regarding the filter, you're correct. The Harley adaptor is not a quality piece. The tests show that it may even restrict oil flow. On most models the gasket is of incorrect design for the adaptor. You can put a Jagg 10 row cooler and adaptor on it. If it's an 09 or 10, the Jagg low mount is not what is shown on the site and is not a good looking cooler; the lines are a mess. Jagg (IMO) did not come up with the right design for the new frame change. Also, and I'm not sure of this, Jagg's 10 row might ride a little low to the ground making it a little more liable to road debris as far as I can tell from they're pics. You can use they're vertical but most of use prefer the low mount.
Here's what I did on my 09 Road King. I used the HD cooler, bracket and lines and I bought the Jagg adaptor. Best $100.00 I spent. It blows away the HD and its design is such that it doesn't restrict oil flow by routing the oil through the filter first. I bought the one without the thermostat. Jagg will tell you a thermostat is absolutely not necessary, but that's your choice - either works. This is the key. You can use the HD pre-molded hoses with the Jagg adaptor. While the inlets and outlet are under the oil filter on the Jagg adaptor versus above the filter on the HD, you can flex them downward and they work perfectly. My system is running 20 degrees cooler with this set-up and Mobil 1 Syn. This did not occur on my Dyna where I did the same except used the HD adaptor.
Regarding the filter, you're correct. The Harley adaptor is not a quality piece. The tests show that it may even restrict oil flow. On most models the gasket is of incorrect design for the adaptor. You can put a Jagg 10 row cooler and adaptor on it. If it's an 09 or 10, the Jagg low mount is not what is shown on the site and is not a good looking cooler; the lines are a mess. Jagg (IMO) did not come up with the right design for the new frame change. Also, and I'm not sure of this, Jagg's 10 row might ride a little low to the ground making it a little more liable to road debris as far as I can tell from they're pics. You can use they're vertical but most of use prefer the low mount.
Here's what I did on my 09 Road King. I used the HD cooler, bracket and lines and I bought the Jagg adaptor. Best $100.00 I spent. It blows away the HD and its design is such that it doesn't restrict oil flow by routing the oil through the filter first. I bought the one without the thermostat. Jagg will tell you a thermostat is absolutely not necessary, but that's your choice - either works. This is the key. You can use the HD pre-molded hoses with the Jagg adaptor. While the inlets and outlet are under the oil filter on the Jagg adaptor versus above the filter on the HD, you can flex them downward and they work perfectly. My system is running 20 degrees cooler with this set-up and Mobil 1 Syn. This did not occur on my Dyna where I did the same except used the HD adaptor.
Road Captain
Joined: Jan 2009
Posts: 739
Likes: 2
From: St. Louis
Your reasoning is somewhat skewed. HD routes the oil through the filter first for a reason. You want the oil filtered before going through the oil cooler. The hot oil flows much better than cool oil does. If you cooled the oil first, it would become more viscous and not flow as well. There is actually less of a restriction doing it this way. Just trying to shed some light on their reasoning.
Grand HDF Member
Joined: Dec 2007
Posts: 4,999
Likes: 55
From: Bay Area
I just remembered also by using those relief plugs for oil flow your oil will forever bypass the filter because of the path of least resistance. Which means your oil wil never be filtered.
HD Forum Stories
The Best of Harley-Davidson for Lifelong Riders
7 Surprising Harley-Davidson Products that Are Not Motorcycles
Verdad Gallardo
8 Best Harley-Davidson Motorcycles Ever
Pouria Savadkouei
10 Worst Harley-Davidson Motorcycles Ever
Pouria Savadkouei
Killer Custom's Jail Break Is The Breakout That Refused to Blend In
Verdad Gallardo
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Verdad Gallardo
Harley-Davidson Reveals Super Cool Cafe Racer Concept
Verdad Gallardo
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Verdad Gallardo
10 Motorcycles You Should Never Buy
Joe Kucinski
10 Things Harley-Davidson Needs to Fix in 2026
Verdad Gallardo
Road Master
Joined: Jun 2008
Posts: 986
Likes: 3
From: Texas
It could be deposited on the tubing wall or even blocking flow completely.
Thread
Thread Starter
Forum
Replies
Last Post
