Summer is coming The K is getting hot!!

[Gingerchunkyboy]

The problem with having a shop do your maintenance that involves removing the radiator is that they do not clean it as well (or at all) as you would. It takes at least an hour to pick out the rocks and bugs from each individual fin hole, me a couple of hours. You need to air blow it while doing this. Generally you get 30 or 40 grams of crap. Now spray some brake cleaner solvent in to get the road tar stuff out. Now wash with soap and water and rinse. You will be amazed how this helps. Shops don't want to do this because of the two hours time. How do they ask you for the money for this. Many Dealers just say it is done and sell you a new radiator. Yikes. Yes, your first complaint indicated your "mechanic" did a poor job. No vacuum bleed. Don't go back.

I would agree when i clean my K1300s radiator on a 70K bike i always soak in a parts cleaner, then jet wash with a power waher then, one cycle in the dish washer (when the wife goes out)
takes most off the day . I do this every time i change the plugs at 12000 miles.

[DuncanH]

Well, I have done around 200 miles since the service and a mixture of dual carriageways and very slow town riding. All is fine- 3 and 4 bars and the fan has not come on yet I understand the point of the stone guard but I am using an extra long fender extender and, to be honest, it would have to be a fairly large stone to penetrate the plastic grille. I have had an XR 1000 and an S1000r and they did not have stone guards. The K radiator is mounted low- its a risk without the guard but it stays a lot cooler without the 4" plastic slab blocking the radiator. I had an early K1600 with overheating problems- removed the stone guard on that bike and it improved the cooling.

It's a sign that the cooling system is not working to peak efficiency and will before long need some attention.

Agree.  Either the rad is clogged (which they're very prone to) or it wasn't vacuum filled properly.  Lowish level in the overflow tank shouldn't cause the overheating per se but could be a sign that it wasn't properly vac filled. I'd have the rad off, check it, clean it, get a good second hand replacement if needed, vac fill it and put the guard back on (it stops a lot of muck so leaving it off can only be temporary and a good, well bled rad works perfectly with it on). Personally I wouldn't trust the mechanic but that might be unfair here.  I've got a good vacuum device if you need it and are anywhere near London.

[commando 848]

The service was carried out at a place in Chessington which specialise in BMW motorcycles MSR- Motorrad service and repair. They have good reviews and reasonable labour charges. But the fact remains that you dont know what goes on behind the doors!. I like to carry out my own servicing and know thats its been done properly. I am beginning to suffer paranoia- check the weather forecast for rain- dont want road debris blocking the radiator , Avoid speed humps to give the ball joints an easy life , cover the switchgear up on a sunny day!!
But, at the end of the day, I have never ridden a bike that is so right. I think that most owners would agree. Thank you Duncan for your kind offer- I my take you up on that. I know Barnes well- my in laws live in Ham.       

[armstrongracer]

I'm probably doing it all wrong but I jet wash my rad every week using the lance in a garage forecourt. Bike used in all weathers and kept outside, sees rain at least 3 times/week. 23K miles and I rarely get more than 3 bars and fan only ever comes on if I'm stationary in traffic for a long time. Theory that I'm sticking to is that it's so wet here that the crud never gets a chance to set into a concrete skin  . Always kept the stone guard on.

[Phmode]

I'm not riding in the Emerald Isle but 'my' theory would be that you are driving the crud (if it is there) deeper into the radiator fins.

I always wash from the back of the rad with fan removed and using the very nifty Karcher right-angled head attachment on a low setting.

[Sutty]

I tend not to ride mine in the wet but when I do I wash it as soon as I can. I use a snow foam on the Karcher, it penetrates really well, then hose it out, you can see by the colour of the rinse water it’s moving the shit.
I’ve removed the crud catcher and find it cools better. When I serviced it I noticed the my compressor didn’t drive enough vacuum in the system to reach the BMW recommended level even though it was showing green on the gauge.
I made up a vacuum pump from a garden sprayer that generated more than enough vacuum, it filled in no time.
I also altered the valve set up  from the fill tank to stop any air getting sucked in when filling.
Regards.  Mick