R1100/R1150 Hot running

[NonComp]

The point is that there is likely not enough cooling of the exhaust stream by the oil cooler to save your plastic from melting. See this thread for more info:

 

http://bmwsporttouring.com/ubbthreads/ubbthreads.php?ubb=showflat&Main=48481&Number=530654#Post530654

[japachap]

Both you chaps are correct, to a certain point. Any increase in heat dissipation from one part of the system will decrease the heat at another part of that system. However, the chance of cooling at the radiator creating any noticeble (or even measureable) difference at the exhaust headers is extremely unlikely. Im actually with GlenTs last post on this one!

 

You will never see an exhaust header glowing hot at tickover- even on fast idle, and its better to view the two problems as completely separate.

 

I used to bask in the glow of hot headers when I used to arrive home late after a nights disco dancing- a bike ridden hard. Yesterday, I had the opportunity during some unseasonably agreeable weather to have a blast around the German backroads. Got home at dusk and could see a distinctive glow. Quite simply- header temperature rises rapidly with rpm and if the cooling due to the bikes forward motion suddenly stops then the radiated/convected heat from the headers has nowhere to go except the panelwork. I reckon thats why I have a little warping- riding too hard and then switching off without a 'cooling down' riding period (ie, low rpm- medium airspeed riding).

 

The only viable way I can see to protect the fairing if such a problem was to occur regularly would be to fit an aluminium or thin stainless heat shield from the four fairing screws around the exhaust- allowing maybe a quarter-inch between the shield and fairing for airflow. Alternatively, extra fans in/ near the cylinder heads- but this I feel is really, really,really unnecessary (and this comming from the guy who began this thread!).

[flars]

"...You will never see an exhaust header glowing hot at tickover- even on fast idle..."

Hey Randy - you want to disabuse him of this false thinking???

To expound on this - Randy's GS had one header glow cherry red at idle during a tech day - and it did so after less than a minute. The BMW shop had to fix it, cuz we weren't smart enough to figure it out.

[NonComp]

I think the point that japachap was trying to make is that if you are riding along the freeway on a hot day, and then suddenly have to come to a full stop because of traffic conditions, an oil cooler is not going to be able to sufficiently reduce the amount of heat coming off the headers as the bike cools to idle temps. In other words, fans on the oil cooler are not going to save your plastic under certain conditions.

 

So, even if you have the RTP fans installed, don't count on them (alone) to prevent your plastic from melting, when (for example) you are doing a TB sync and running your bike stationary at 3000 rpm for extended periods of time. As noted in the other thread, some consider the plastic melting from header heat to be a separate issue.

 

By the way, this should be measurable. If you have an infared thermometer, you could compare header temps (at the same spot and distance from the header) with and without the fans running, under controlled conditions, such as riding for 10 minutes on the freeway, then pulling off and leaving the bike at idle on the center stand and sampling the temperature (on a windless day) every 60 seconds for 5 minutes. You would have to see a peak temperature reduction as well increased rate of temperature fall in order to prove that the fans made a difference in protecting the plastic.

[ratfink]

I would agree that at higher rpms the the fan becomes a moot issue.

 

It is also at the mercy of ambient temp.

 

GlenT: I would welcome you to bring a standard RT down here to Vancouver USA and park it in my driveway. I will bring out my RT-P and we can idle them for 45 minutes or so and record Temperatures at the exhaust headers.

 

I'll supply thermometers and data loggers along with a couple of fire extinguishers just in case your bike cathes on fire.

[NonComp]

Ratfink, I have an unfair advantage -- no plastic. My avatar is my bike. My ST1300, on the other hand, can sit all day idling, with its liquid cooling, big radiator and twin fans.

 

Having said that, I think that the opinions expressed here by several people who have a lot more experience than I have with these bikes, is that there has never been a confirmed case of an oilhead being seriously damaged by extended idling, except in the unfortunate cases where people have left the bike on high idle to warm up and forgotten about them. But that's another issue.

 

And in any case, what would that prove? Two different bikes, if not fresh from the factory, would not be comparable. Different fuel. Different oil. Different state of repair. Different mileages.

 

And aside from police officers, why would anyone let an air-cooled vehicle sit stationary and idling for 45 minutes? Stop and go is stop and go. It is not sitting stationary 45 minutes. Most right-minded owners would shut their bikes off.

 

I think that the test I suggested would be more valid. One bike with and without fans running. Minimize the number of variables. Check the cool-down rate and max temperature. I don't think that anyone needs to intentionally put their bike in harms way to prove this point one way or the other.

[ratfink]

My friends with RT's don't want to submit their bikes for this test either, but they have expressed a willingness to stand fire watch, take video and supply plastex and touch up paint.

 

I did invite you to aquire a standard RT for the test. Your naked boxer or ST wouldn't do, so I agree on that.

 

I'm just confident that my RT-P will idle for long long periods of time without sustaining damage. Nobody in their right mind would intentionally do this with a standard RT. Some that have inadvertently done so, have paint or plastic damage to show for it.

 

I will sign off this thread by saying "I like my fan" I like the OP's fan too.

[NonComp]

Nobody in their right mind would intentionally do this with a standard RT. Some that have inadvertently done so, have paint or plastic damage to show for it.

That doesn't prove that an RTP fan would help, or that it is needed to prevent plastic damage during prolonged idle. As twisty said, it wasn't a concern until BMW put a temp guage on the oil.

 

I will return your challenge:

 

Put in a temporary switch or jumper to bypass your thermostat so that you can run your fans anytime. Then perform the test that I suggested. You appear to have access to the equipment needed. Note that you will not have to wait for the bike to get hot enough to trigger the fan and/or cause damage. It is the temperature differential that we are interested in. If the fan made a difference, it would result in measurably lower header temperatures and measurably faster cool-down of the headers.

 

So prove it.

[ratfink]

GlenT:

 

Really my first post on this thread was intended to compliment the OP on his his design and construction of his fan and for his excellent video production. Further, I wanted to offer my opinion on what will be fruits of his labour, based on my personal expeience.

 

My testing challenge was made tongue-in-cheek as an illustration and I was hoping you would see the humour in it. Pardon me if it was lame.

 

I still invite you to come on down, our time would be best spent out riding and agreeing to disagree. A ride up to Mt. St. Helens is one of my favourite for out of town visitors on holiday.

 

You might want to bring your roadster, we sometimes engage in spirited riding even with fully laden panniers.

[NonComp]

No problem, Ratfink. I'm always up for a debate and I do find this subject interesting. Alas, the roadster is off the road waiting for an ignition wiring harness from Motobins and the ST1300 was officially put up for the winter this past weekend. I'm now riding the bus to work (**shudder**). Maybe see you next April.

[ratfink]

Yes, debate can be like a hard played football match. Maybe the ref showed a few yellow cards and the score was null for both teams.

 

Some of the blokes on the other team are your mates. At the end you shake hands and retire to the Pub and commiserate over how unfair the ref was.

 

The wiring harness? Is that at the HES, or something else. Sorry if that is OT. I'm just curious and didn't want to start another thread.

[NonComp]

No, this is another known issue. The bundle of wires that run around the steering head were often cynched too tight by wire ties. As a result, the ignition wire(s) sometimes break in the bundle running down from the ignition key/switch. In my case, two wires were worn through at the connector on the base of the key/switch. I am going to have to order a replacement as there is not enough wire left to solder to and the wires are corroded. I also found a third wire broken in the bundle that runs to the headlight and instrument panel. Symptoms were engine cut-out when the handlebars are turned off-center.

[Steve Parry]

Japachap, any update? Did it work well in the summer for you?

[japachap]

Japachap, any update? Did it work well in the summer for you?

 

Greetings Steve,

 

Lucky I have this topic on a watch list otherwise I wouldnt have seen your post (I dont come here much anymore- too busy with life and I keep it local now- BMRider.com and BMWRTForum.nl )

 

The fans have been on the bike four years now and have only been removed once for a quick blact of brake cleaner and a smidge of WD40. They are driven by brushless induction motors and Ive been very surprised at how durable they have been!

 

Have they had much use? Not really!

 

I tend to flick them on in the plus-30degC days, but havent had a single occasion when the bike has overheated since- even on the plus 35degC days this Dutch summer...

 

Why is this so? No idea.

I have become more adept at servicing the bike the past 5 years, so maybe a good tune-up helps. I also started running NGK Iridium sparkplugs and fitted a 1000ohm resisitor in series with the air temperature sensor to richen the mixture a little. It could be that the bike was running too lean...

Other factors? Been trying different oils. Stopped with the dealer-supplied Castrol and went to Motul Boxer- then this year to Castrol FST 5w60 car oil for the BMW M-series engines. As the bike has no wet clutch it doesnt matter that it doesnt have a 'bike' oil in it. The FST standards are superior to those recommended in the owners manual and I bought it at half price for 5L in a local promotion- which worked out cheaper than the regular 4L of bike oil! The bike runs nice with this new oil in.

I also feel that the bike only really got run-in 3-4 years ago- around the 36000 mile service. Its on 60,000 now and Im still very happy with it.

 

 

I still think the time and effort spent in making the cooler fans was worth it- just for the peace of mind.

 

If you want to find my posts on either of th eother two forums, look for the usermane 'japachap'.

 

Reagards,

 

James