Mac 4-1 with factory oil cooler question

[markb80]

I found a couple threads on this topic, but not a clear yes or no yet.

Looking to put a MAC 4-1 on an 80 xs11 special (and/or a 78 xs11 standard). I have a couple factory oil cooler setups. By factory I mean the system that had metal lines which attach to the adapter plate with O-rings, and mount close to the engine, then have a 1 foot flexible section of hose, and then thread-on fittings to the cooler.

The MAC 4-1 seems to swing out to the right side of bike pretty well and may allow the filter cup and hoses to clear, even with cup sitting an inch lower due to the adapter. Has anyone used this combination? MAC used to say it would not work with the factory oil cooler, but I understand they may have changed the system about 10 years ago so that the collector is off to the side more. I have an old Racer-1 system that kind of works with the factory cooler, but the cup winds up about 1/2-3/4 inches from the collector because it sits lower with the adapter plate installed. The system is in good shape, but has been repaired a couple times.

Just curious if the MAC would work out better for use with factory oil cooler, any info is appreciated, thanks

[Mashermoto]

Mark I got your email from Allxs11s about this question. I'm having trouble visualizing your situation. Can you post some pictures

[markb80]

I can't post pics of the MAC exhaust as I don't have one yet. The Racer 1 has all 4 headpipes going to a collector that is non in the middle underside of engine, but off to the right a bit. That allows access to oil filter. But with the adapter plate on for an oil cooler, the cup sits about an inch lower. The oil filter cup would otherwise be higher than the collector, but with the oil cooler adapter plate it sits next to it. That makes the cup sit about 1/2 to 3/4 inches from the collector. The cooler may cool the oil, but the collector may heat the cup, eliminating the benefit. I haven't even looked at hose/pipe interference in front. So just curious if anyone has tried the MAC 4-1 system with a factory oil cooler (factory type had metal lines that attach to the adapter plate that then go into flexible lines and then to threaded fittings to cooler).

[Mashermoto]

Mark,

According to Oldbikebarn.com, you are out of luck if you want the stock oil cooler

They posted: "High performance 4 into 1 exhaust systems with upswept megaphone features center stand retention, removable all steel baffles, ground clearance, easy access to oil filter and drain plug. Quality Chrome Plating. Does not fit models with factory oil cooler. Some 80 Models may require spacers be used on exhaust studs."

Can you post a picture of your Racer 1? I would like to see what it looks like.