Fan cooling logic?

[BRatigan]

I just did temperature testing on my 08 Uly and found that the temp was 25 degrees F hotter on the rear cylinder than the front at shutdown About 289 F for the rear. By the time the fan shut down (about 4-5 minutes) the temps had evened out at around 200 plus or minus. The fan should come on when engine temps are at 320 degrees F. This is with the 08 fan logic not the upgraded logic. I also run the comfort kit right side scoop, Special OPS fabric barriers and my own underseat and right custom heat shield mod. Heat is not an issue anymore.

BR

 

[brightbuell]

Get the right side scoop it works great. They all work the same if they are the same size but some look like shit others look great, the prices fit the looks. Some are cheap some cost $270 shipped. Mine was $270 but it looks great.

 

[hjohnsonjr]

A lot is being said about the fan. I have the latest software in my 2006. It is close to a hundred F here in Oregon today and the fan is not running. I pulled the seat and put a surface type thermometer on the top of the head and got 250. Troubleshooting does not look easy in the book. Can I use a VOM instead of a "breakout box" to troubleshoot?

 

[stevengeorgia]

Doesn't the "comfort kit" come with a right-side larger air scoop? And does it include the exhaust shield as shown in the pic?

 

[user_deleted]

I have a RH scoop on my baby that pushes air to the rear cylinder and it only runs when I turn the Key off now

that right there. and synthetic oil. RSS available thru any H-D dealer either online or in person. you will need to purchase the outer scoop, inner scoop and 3 specific-sized torx screws. i've posted the 3 H-D part #'s on here numerous occasions. total about $60 for all 5 items.

 

[GregoXB]

So interesting factoid. If you get the EBR Race ECM it uses the 2010 and later fan logic. As far as I was told from EBR it will not run at shutoff anymore or at low speed as often (I think they raised the temp it kicks on at) but it runs more when you are on the road over 45MPH. This is all what I gathered from a phone conversation with them so I don't have any exacts.

I can confirm this. I got an EBR ECM for my '09XB 12Ss before anything else, and it significantly changes the behavior of the fan. The fan turns on while I am on the throttle, cruising, when I can barely hear it. When the bike is at a stop or turned off, the fan is off as well. On the stock ECM, the fan would activate at a stop, while cruising and when the bike was shut off (very annoying).

The modifications that minimized fan operation in order from most important to least important are as follows:

1) EBR ECM
2) Amsoil
3) RSS

I would NOT do any other modifications before you tried those 3 solutions. I am EXTREMELY pleased with the operation of my fan after I did the above steps.

 

[anrkizm95]

So interesting factoid. If you get the EBR Race ECM it uses the 2010 and later fan logic. As far as I was told from EBR it will not run at shutoff anymore or at low speed as often (I think they raised the temp it kicks on at) but it runs more when you are on the road over 45MPH. This is all what I gathered from a phone conversation with them so I don't have any exacts.

the fan will still run when shut off if its hot enough and comes on at speeds over 15 mph not 45.

 

[GregoXB]

^
In my personal experience with the EBR ECM, even riding in 90+ degree weather, when I turn my bike off the fan does not come on.

It WILL come on at speeds +15mph but will shut off when I release the throttle and brake to a stop, like at a stop light.

 

[DualSportDad]

In my personal experience with the EBR ECM, even riding in 90+ degree weather, when I turn my bike off the fan does not come on.

It WILL come on at speeds +15mph but will shut off when I release the throttle and brake to a stop, like at a stop light.

You have a RSS, your temps probably aren't high enough for the fan to come on. In 90 deg temps my fan doesn't come on either with a RSS, without it seems to run very often.

 

[GregoXB]

You have a RSS, your temps probably aren't high enough for the fan to come on. In 90 deg temps my fan doesn't come on either with a RSS, without it seems to run very often.

Negative. The first modification I did to my '09 XB12Ss was an EBR ECM with 2,000 miles on the odometer. Upon this change, the fan behaved as I described. Adding RSS and Amsoil made the bike FEEL noticeably cooler.

 

[GregoXB]

http://www.erikbuellracing.com/store/models/xb12/xb12-preprogrammed-ecm.html

***You may notice different cooling fan operation with the EBR ECM for 2008-2010 model year bikes compared to the operation with your stock ECM. This is normal due to the revised cooling fan strategy that is programmed into these ECM's.***

Straight from the horse's mouth.

 

[axegrinder]

I have D&D exhaust and Buell racing ECM. Unless it below 50 degrees the fan runs constantly when moving. It will shut off at speeds below 10 MPH. On a very warm day, it might come on for a minute or so when turned off. I figure Eric know what he's doing so I've never questioned when the fan wants to run. Even when it does come on when turned off, it doesn't bother me. You're getting 103 HP from a pushrod V twin so you know it's gonna need cooling. If the bike runs well, just let it go.
Cheers.