oil temperature
 

Does anyone know what average oil temperature should be on a R100GS. I've just fitted a 43ltr tank and therefor changed the position of the oil cooler with the aid of the 'Touratech' relocation kit. I've also fitted an oil temperature gauge in place of the dip stick. This gauge reads between 100 and 120 which seems a bit on the high side.
....Bob

I thought of posting this article but it is much too long and it does not specifically answer your question. But it has some good information. It is from the airheads.org
http://www.airheads.org/contrib/oils.html
John

Max oil temperature according to oil companies is around 240 F or 115 C.

However, it's not unusual for an airhead to hit 270 F (132 C) or so without an oil cooler, in hot climates and loaded.

With an oil cooler you should get a max temp of around 235-2450F or 112 C to 118 C.

With an oil cooler I'd be very surprised to get 120 C (248 F) in the UK. Either something is very wrong or your gauge is no good. Is the cooler hot to the touch? Perhaps the system isn't working and passing oil to the cooler.

Note that an oil cooler is worthwhile for ANY airhead on a long trip, especially R100's.

The HPN thermostat is especially worthwhile on an R100GS, as they don't have a thermostat, and take forever to warm up in cold temperatures - also not good! It's set to begin opening at 90C and is fully open at 110C, so that gives an idea of the temperature range they expect for moderate conditions.

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Grant Johnson

Seek, and ye shall find.
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One world, Two wheels.
www.HorizonsUnlimited.com

Thanks for the replies. Grant, the oil cooler is hot so I presume that the oil is reaching the cooler OK. I now think, at least, part of the problem ("OH REALLY") is that the rear of the high front fender sits directly in the way of the airflow to the oil cooler with only a few millimeters clearence between them. I could put more spacers and lower the fender, but this wouldn't increase the gap by much. I know 'Acerbis' make a front fender with "vents" so I could give that a try or cuts slots in mine and put some fine mesh over the slots to protect the cooler. Has anyone experiance of the 'Acerbis/Touratech' fender ?

The other thing is that the tank sits right over the cylinders and reduces the amount of airflow around them. Obviously there isn't alot I can do about that.

I'll seriously consider the thermostat as I'll probably use the bike during the UK winter prior to our RTW next year. There was a thread regarding a second hand one somewhere on the site, I'll have a look.

As far as I can tell the gauge is fairly accurate. I'll try boiling water and stick the gauge in it.

..Bob

[This message has been edited by mcdarbyfeast (edited 21 September 2002).]

I currently have the Acerbis "Baja" fender on mine - with the vents in front of the cooler. Fits well. I currently have the vent closed, but in really hot weather I'd probably open it up - if I thought of it. A wire mesh is probably a good idea.

Let me know how the temp check works on the thermometer.

The tank on top of the cylinders shouldn't be a problem, unless you're sitting around idling a lot (a real no-no, very bad for the engine as it WILL overheat rapidly) and then it's probably only a small difference. As long as you're moving the tank will have NO effect on cooling. Look at my front boxes - no problem and they cover the cylinders more than a plastic tank.

(more to the point is you're really heating up the fuel when you sit and idle! Some people have put silver heat duct reflective tape on the tank to reflect the heat away, but I doubt it matters a lot.)

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Grant Johnson

Seek, and ye shall find.
------------------------

One world, Two wheels.
www.HorizonsUnlimited.com

I checked the gauge by filling an old beer can with boiling water then put the gauge into it. The reading was 97c, so pretty accurate.

I cut a slot into the rear of the front fender, about 2" wide and about 5" long but left the bottom part attached, then bent the flap forward so as any crud thrown up from the road wouldn't hit the oil cooler. It has made a huge difference to the oil temperature. The gauge now reads 100c while being driven on the open road and creeps up to about 110c in heavy traffic.

I've checked the bottom of the tank, above the cylinders, it does get warm to the touch but not hot.

I've decided not paint the tank, as it would make it look to pretty and attract the wrong sort of attention. I marked it off in gallon increments (I stole this idea from a guy I met at the UK 'Horizons' meet ealier this year)

Thanks for all the info....Bob

I think Grant may disagree with me but, I don't think you need an oil cooler.
I was riding with a friend who was on a 91 R100GS. One of the hose fittings
with a piece of the oil cooler broke off of the cooler. I know of two other
people who have had failures in the fittings and core ruptures.
I know of one BMW dealer who advised people to remove the oil coolers
because of these failures.
His reasoning was that you are better off without fittings, hoses, cooler
cores out in harms way. Especially on a bike that may be going off road.
With the cylinders sticking out in the air you get the best possible cooling
on a air-cooled motorcycle.
It is far better to keep the oil in the engine and to change it on a regular
basis.
I remover the oil cooler on my 92 R100R with about 20,000 miles on the bike.
I now have 159,000 miles on it. I have had the rings replaced twice and at
140,000 miles the heads rebuilt but so far I have not had any problems that
could be related to oil and over heating. I live in Nevada and do most of my
riding in the desert and it is not uncommon to be riding in temperatures
over 100 f ( 38 c).
Thanks, I feel much better now.
Grant do you really need an oil cooler?
John Ferris

As with most things, "need" is relative. Is a cooler a "good thing"? Absolutely. It will keep the oil temp lower and that is without doubt a "good thing" - ask any oil company rep what he thinks of oil temps in the 120C + range - it's not good!

Note the temp differences Bob got from a blocked cooler to unblocked - pretty significant. And his high temperature of 120 is definitely over oil company max recommendations of 115C - and that's WITH a cooler, just not doing a lot - without the cooler I'm sure it would have been a few degrees hotter still - and that's in the UK, not exactly notorious for it's hot weather. http://www.horizonsunlimited.com/ubb/smile.gif

I have no doubt that John has the mileage he has, and many others will tell you the same story - BUT that doesn't mean that the engine is as healthy as it could be - especially main bearings and crank, and camshaft - all needing cool oil for the best lubrication possible - and perhaps not getting it as often as it would with a cooler.

Where the cooler is critical is in hot hard slogs uphill in first gear, or through desert sand, or two-up fully loaded in the mud, or in Cairo traffic jams.

Can you get away without a cooler? Sure. But BMW didn't put it on the 1000cc engine for no reason - THEY thought it was important enough to put it in a stupid location.

You pays your money you takes your chances.

John, I'd be interested to see what temps you are getting down there?

As for the cooler location, use the HPN kit to get the cooler off the crashbar - one of the all-time stupid decisions any manufacturer has ever made - kudos to BMW for it's entry in the "Stupefyingly Stupid Ideas Hall of Infamy"

As for cooler failure, HPN makes a bypass kit for just that purpose. Carry one.

------------------
Grant Johnson

Seek, and ye shall find.
------------------------

One world, Two wheels.
www.HorizonsUnlimited.com

Hi Guys, thanks for all your help.

I'll keep the cooler and fit a thermostat before the winter. I've already ordered a bypass kit to take with us next year.

...Bob

Help !

I thought I'd cured the overheating oil with the modifications made the front fender, but the problem has returned. The gauge now reads 115c to 120c most of the time, ambient temperature is around 21c in the UK at the moment. Having tested the gauge I'm fairly confident its working OK. I'm also happy that the mixture is right IE: not running to weak, as the plugs are a good color (lightish grey, not white) I've changed the oil and filter, adjusted the valve clearences (I noticed that there was a little blueing on the rockers, I don't know if thats normal) and balanced the carbs. The engine runs pulls strongly and cleanly. Ocassionally when 'cruising' at around 30mph (three to three and a half thousand revs) the engine doesn't run quiet as smoothly and feels like its holding back, but its hardly noticable most of the time and doesn't happen and any other speed or RPM. Fuel consumption is around 40-45mpg (I live in a semi-rural area and the roads are a mixture of slow country lanes and 'B' roads) The cooling fins are clean. There is a small 'spoiler' fitted to the front of the bike, just infront of the sump guard. This does cover the front of the cylinders slightly, but I wouldn't have thought would make that much difference.

Am I being paranoid or is there a problem..!!

Sounds like somethings not quite right, BUT it could be ok - it's kind of on the border line.

I suspect the gauge, not the bike. This type of gauge isn't notorious for it's accuracy.

Can you try the gauge on another BMW?

Contact the seller of the gauge - what sort of numbers does he get with it?



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Grant Johnson

Seek, and ye shall find.
------------------------

One world, Two wheels.
www.HorizonsUnlimited.com

Hi all.
Sorry for being slightly off topic, but I've always wondered what will happen when I drive my R1150R to India and get stuck in traffic in Bangalore. The ambient temperature should reach far above normal summer weather temps here in (c)old Norway, and with a lot of standstill, short go's and then stop's and standstill again, I've always suspected that the oil temperatur should rocket sky high. Probably well above recommended oil temperature. Then again I wonder: Would BMW actually build an engine with a cooling system that couldn't take this? In Germany bikers aren't allowed to split lanes in case of traffic jams, so they must follow the queue - which means standstills, stops and go's. Any idea, Grant?

Best regards
Indu

Haven't had any reports of overheating problems with the R1150, but it certainly COULD overheat. I wouldn't worry about it, just be aware, and be prepared to turn it off if you're stuck in really bad conditions for a long time. Generally as long as you're moving a little, you should be ok.

Would they build a bike that CAN overheat - of course! ONLY watercooling has a hope of never overheating - and even then only if they have a fan to cool the radiator. All of which adds weight and complexity and cost.

It's always a tradeoff for the manufacturer - we complain about the weight and complexity and cost, so they build it simpler, then we complain about overheating, lack of power, weak brakes, no heated seat, weak electrics...

------------------
Grant Johnson

Seek, and ye shall find.
------------------------

One world, Two wheels.
www.HorizonsUnlimited.com

hi
thought i'd add my grain of salt to the discussion: i did 140.000km on my '89 r100gs (with acerbis fender and 43 litre tank and a lot of luggage, with modified oil cooler).

the oil temp was regularly around 120 or 130 degrees. i monitored the temperature... anything above 140 degrees necessitated a stop to let the engine cool down. this only happened very very very occasionally, usually going up very big hills/mountains with a tail wind (working hard and no cooling influence). in the rain the engine ran much cooler, of course, but i enjoyed it less http://www.horizonsunlimited.com/ubb/frown.gif

i met a swiss fellow (also a bmw mechanic?) in cape town who had small electrically powered fans on each crashbar so that there more air across the engine.

i'm not convinced how well the oil cooler works when relocated. mine was always covered in dirt.

i can't say i did an empirical research, but i found that after an oil change the bike ran cooler for a while... so be nice to your engine... change the oil quite frequently. it is easy and oil is cheap.

the engine on my bike was the only thing that behaved itself. pretty much everything else attached to it failed.

good luck,
cb

Hi,

Just a final word from me.

I asked the same question on the GS UK coms board site. I had several replies from guys who were using the same gauge, made by 'RR' Everyone who replied stated they regularly get readings anywhere from 100c to 120c even in the UK.

I'm now stress free and will worry no more!(at least about my oil temp')

...Bob

[This message has been edited by mcdarbyfeast (edited 05 October 2002).]