Got stuck in traffic on the way home from work yesterday. Temp was about 86F and humidity was high. I was afraid my Ultra was going to overheat so I crossed the median and took a longer way home. My question is, how much idling and stop and go can one of these engines take (96 ci) without getting too hot. My last touring bike was liquid cooled so that was something I never thought about. I don't get stuck in traffic often but when I do, I don't want to risk burning my engine up. Thanks,

SugsPa

 

If you're really worried about it and you live in an area that gets really hot you could add an oil cooler to your bike. Your bike also has a heat management system where when the engine gets to a certain temp it shuts off the rear cylinder to help out. When you roll the throttle on the rear cylinder comes back online. Also running synthetic oil will help with the heat.

 

same thing happened to me, after about an hour of interstate riding came upon a construction zone and traffic crawled along for almost an hour, bike's heat management system worked fine but the bike still almost died a couple of times due to the heat, I know HD lovers really like the air-cooled aspect of the bikes but I think liquid cooling on these big tourers is long overdue.

 

Was just talking to HD dealership about this yesterday. I live in Hot central Fla and the conversation got around to the heat management system-make sure its on. Then they said I should run 60 weight oil for summer. Not 20W-60...straight 60 weight. Does that sound right??? it does get hot here- setting another record in central FL today about 96..around 68 at night already- Going to be a long hot summer.

Postman
2011 FLHTK
Leesburg, FL

 

You should be fine...with the heat management system and using synthetic oils. Yes they run hot during the summer. I would recommend taking off lowers (but that's up to you). I have soft lowers i can just snap on and off. Some people run with their lowers on all year long. These bikes are made for this and usually my biggest complaint is my leg starting to get hot!!!!! I installed a set of fairing vents that help push more air flow while moving and keeping the bike cooler.

 

My 2011 RGU 103 runs hot so I installed the Lenale cooling fan where the horn mounts. It does a good job of cooling the motor in parade/traffic jam conditions.

 

Yeah, same here, but that's par for the course I guess. I have been riding Harley's for years so I have dealt with this for a long time. I just got a 2011 Ultra Limited this year though and still have the stock exhaust on it. It was 97 degrees when I left work yesterday riding in and stop and go rush hour traffic got a little warm. Might be putting on a new exhaust sooner than later...

 

As stated above, you have the heat management system on your bike, an oil cooler won't hurt, and there are a few products on the market to help keep the heat off your inner thighs. I just bought an ultracool oil cooler, I figure if I'm sitting, a regular cooler isn't going to help a whole lot, and I'm also looking into an engine fan. As for liquid cooling, my second bike is a VTX it is cooler, but if I wanted a liquid cooled HD I'd buy a V Rod.....

 

SugsPa, I think the real question is what is too hot. I've been trying to find a qualified answer about this myself without any success thus far. These temp threads always get out of control. The determining conditions are the combination of material thermal chacteristics of the cylinders, heads, valves, pistons, and rings, which are all components the combustion chamber. I mention them all because they are all involved but I would say the material specification for the heads is the most influential factor determining maximum operating temperature. This is only an assumpion, but I don't think, under normal operation, your bike will get hot enough to cause catostrophic failure. It will get very hot and very uncomfortable to the rider, but hot enough to cause mechanical failure, I don't believe so. It's not entirely impossible, but not likely either. When reading forum posts about temperature, I have not yet run across any posts claiming or proving actual evidence of engine failure caused by heat. Cooling or controling heat is not necessary to directly prevent engine damage. However, cooling is not entirely unnsecessary either; cooling to prevent thermal breakdown of your oil, enhance performance, or to improve rider comfort are the most common reasons. I think the reason these temperature threads break down quickly, is because the die hard anti-cooling guys are very adamant that cooling is not necessary to prevent damage, and I think they might be right, but they use that argument to try to discredit all other reasons for cooling. I recently started running an accurate dual CHT gauge, my typical normalized CHT, under normal highway cruising conditions is 270-280F, after comming to a stop, within 2-4 minutes those temps jump up to and a little beyond 340F, my gauge scale only reads to 340. I'm running a fan assisted oil cooler and my oil temps are 205-215F at the same time the CHTs are in the 340F zone. I use this example to show that there is not necessarily a predictable relationship between oil and head temp. Unfortunately I haven't documented any CHTs without the cooler, and I don't have any plans to disable the cooler to do it. I have in the past run my bike without the cooler and when I saw oil temp of 280F+, I pulled over to cool down. My 06 doesn't have the EITMS, so it has the potential to get much hotter than the newer bikes which do have it. Bottom line, I do not have a exact temperature value that defines too hot, and I don't know how long your engine will tolerate low speed or Idle operation before engine failure occurs. You will likely pull over to cool down for your own comfort long before the engine overheats to the point of failure. So, cool it, don't cool it, synthetic, non-sythetic, whatever you do, get out and ride it and enjoy it.

 

Make sure your heat management system is engaged! Do you know how to activate it? If not, look in your owners manual, very simple to do!!