syn oil
Tourer
Joined: Aug 2010
Posts: 340
Likes: 4
From: Peach Bottom Pa.
synthetic oil is about the best thing you can do to any engine,,,it will not cause a leak,,,engine will run a little cooler,,,,and there is less ware on parts,,,maybe thats why your breakin period is 1000 miles with dino oil,,and 3000 miles with synthetic oil,,,
Novice
Joined: Apr 2008
Posts: 15
Likes: 0
I bought a 1996 FLHTCUI in 2007 with 22,000 miles, per the seller dino oil was used, have run Amsoil ever since and have not "found" any leaks. Runs good, won't go back
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Road Warrior
Joined: Sep 2006
Posts: 1,570
Likes: 45
i dont know! my bike seemed to drink the syn oil a bit. i switched to castroll and it doesnt use any now. also my primary started leaking, switched to non syn in the primary and it has stopped leaking also.
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Road Captain
Joined: Mar 2009
Posts: 734
Likes: 0
From: Southern Missouri ( ozarks)
Mobile I and Amsoil did win out as far as a vote is concerned but that was all types of bikes people had on here.
I'm goin back to dino in the motor mid summer when I change. I have the slightest weep at the rear cylinder that wasn't there when I bought the bike. The previous owner didn't use syn.I used Amsoil the 1st year and Mobil I last year and thats when I saw the weep. wasn't going to this spring but I got in a hurry and the local parts store had Mobile on sale for $7.99 and the local indy wanted $9 for reg. HD dino.
I did use Revtech gear oil in the tranny and HD syn3 in the primary and it shifts better and neutral is easier to find.