on a 90 to 95 degree day , what is the acceptable oil tempt at normal highway speeds. My bike is an 03 electric glide. The only mods are stage one and mild cams.

 

Riding the 93 Fatboy this past weekend with the temps in the mid 90s down the freeway at 80 with just a mild cam and not fuel injected and no oil cooler saw around 230 to 240, dropping down to 70 saw around 210 to 220. The newer fuel injected engines will see higher temps.

 

You'll get many opinions on this question, but for my taste I would not want temps to exceed 210° while moving at highway speeds and running synthetic oil . Oil will typcally run cooler going 50mph than at 70mph, too, even though airflow is decreased. If you're worried about oil temp, get a cooler. That will lower peak OT 20° or more and will keep it in control except in the worst of stop-and-go traffic, in which case it will slow the ascent but won't stop it. FWIW, with a cooler I run 200° at 50mph or greater and it hasn't exceeded 220° yet this summer even in traffic, although it has hit 230° a few times over a period of three summers in S. LA only in heavy traffic. That's my emotional limit, as when it climbs that high I'm thinking seriously about shutting it down. This is also running lean AFR's for gas mileage, but I can switch to a richer map on the fly which will lower oil temps when needed. I almost never need to do that with this bike.

If you run synthetic oil you can expose it to higher temperatures before oxidation becomes a problem, but fossil oil will oxidize much faster as temps rise. Some will say that you can run synthetic to 300° safely, but this is not good advise IMO and no categorical safety limit like that is accurate since oil oxidizes at a progressive rate as temps increase.

 

thanks guys for the info. I came home after a ride today an, temp was around the 90 degree mark. When I garaged I checked the temp useing my turkey broiler thermator placed in the oil through the filler hole and the temp was 200 deg. There was just a lot of hot air coming off the motor while ridding. Thanks again for the help. Ride safe.