Auxiliary oil tank

[N. Ohomo]

Hello everyone. I'm starting to put together a R100GS from basket case, 5 years on the shelf. Was running fine when pulled apart save for seized fr. brake caliper.
I'm looking at various oil cooler options, spin on filter kits, sump spacers etc. when it came to mind why not auxiliary oil tank?
Google search reveals nothing (for good reason?) I'm thinking mounted in front on a plate using the four oil pan skid plate bolts. Run the oil cooler lines to it. Dumb?

 

[Kenny]

Well, it may be a first ! No need for an oil cooler anyway. Sump spacer ( if you must have more oil in there ) may be the way to go.

 

[N. Ohomo]

I desire to eliminate the cheesy oil cooler on the crash bar hence my searching various solutions including heat sinks. At this point I think I'm convinced the bike needs a cooler. You don't think so? The aux oil tank in front would act as a quasi cooler as well. I know switching out the rotomolded plastic oil bag on my Buell to aluminum reduced oil temps.

 

[AberdeenAngus]

What summer temperatures do you get over there?

 

[solidstate100]

when it came to mind why not auxiliary oil tank?

I think you might be searching for a complicated fix for a problem you dont have. You can easily dispense with the oil cooler (many many have and reported no ill effects) if it offends you. The beauty of these bikes is their simplicity, why make it more complicated than it needs to be?

If you wish to retain the cooler, it can be relocated to the just under the headstock, there are kits available to do it, that way you retain the cooling, and remove the "cheesy" cooler from the crashbar and which works perfectly - no need for spacer rings (which compared to a cooler have only a marginal effect).

Putting an oil tank below the already existing sump, right in harms way especially with the much reduced ground clearance this would seem to entail seems like madness to me

 

[Rob Farmer]

There are kits to relocate the cooler to a position under the headstock. This is ok if you have the low mudguard fitted.

I think your looking for a problem that doesn't exist. Your bike has run perfectly well as it is for the past 25 years. The highest mileage bikes are generally the ones that nobody has f@cked about with.

 

[electric_monk]

I've taken the oil cooler of my bike about 6 years and 6500 miles ago to no ill effect..

Then there is this one http://www.cynthia.boxerman.co.uk/ no oil cooler and all over the world

 

[solidstate100]

There are kits to relocate the cooler to a position under the headstock. This is ok if you have the low mudguard fitted.

Actually you can fit one under the headstock if you have the high mudguard as well - I have, and there is enough clearance, and I know one or two others that have done it as well.

 

[N. Ohomo]

What summer temperatures do you get over there?

I think you might be searching for a complicated fix for a problem you dont have. You can easily dispense with the oil cooler (many many have and reported no ill effects) if it offends you. The beauty of these bikes is their simplicity, why make it more complicated than it needs to be?

If you wish to retain the cooler, it can be relocated to the just under the headstock, there are kits available to do it, that way you retain the cooling, and remove the "cheesy" cooler from the crashbar and which works perfectly - no need for spacer rings (which compared to a cooler have only a marginal effect).

Putting an oil tank below the already existing sump, right in harms way especially with the much reduced ground clearance this would seem to entail seems like madness to me

Rarely above 85F in the summer and at that prefer not to ride anyway. It's a hobby not a commuting tool.

Maybe I AM looking for a solution to a problem I don't have? Hmm. Intuition tells me more oil capacity is better than stock oil capacity. Maybe the complexity isn't worth the perceived benefit? Could this be politicized? Hate to offend anybody running OEM oil capacity, that is not my intent. I also have a heavily, and unconventionally, braced and de-raked frame. When I mention this to other airheads I get a lot of push back.

Anyway.

I think I'll investigate a horse shoe shaped oil tank/cooler of 1 1/2 tubing that traces the frame down tubes. I have a Triumph Scrambler and for it a company makes frame sections that double as oil cooler. Now, I'm not going to run oil thru my BMW frame but why not mimick that? Did I mention that this is a hobby?

 

[Rob Farmer]

Actually you can fit one under the headstock if you have the high mudguard as well - I have, and there is enough clearance, and I know one or two others that have done it as well.

I know you can but what about the airflow? A few years back the usual thing was to fit the slotted acerbis mudguard.

 

[N. Ohomo]

So high mount oil cooler has airflow issues, others are using no cooler without issue.
Oil cooler under head stock shouldn't be a clearance problem. The generic sumo fender I have could easily be trimmed to clear. That bit of fender aft doesn't seem to provide any useful function anyway.

 

[Beemerboff]

The bikes with the oil cooler have the smallest sump ever fitted to an Airhead, so prudence would suggest that if you remove the oil cooler you fit a more appropriate sump.
But as previous posters have confirmed , these bikes are pretty foolproof and it takes lot of determination and ingenuity to bugger them.
I have both an oil temperature and pressure gauge on my GS, and I actually use it off road. I have a centrally mounted oil cooler, and have replaced the stock sump and its ridiculous little guard with the largest stock airhead sump.
Even with this set up it doesn't take much slow speed off road work to get the oil temperature into the red zone and the oil pressure dropping, and a sump spacer would probably be beneficial - everybody who tunes and /or races an airhead fits one, for good reason. I have a water cooled bike I use for the serious hot weather off road stuff.
Ignore the braying of the jackasses , your bike needs more oil if you intend using it as it was intended.
Ground clearance just isnt an issue, so either a decent sized sump from someone like Niche Supply, a spacer from anyone who sells aftermarket parts or a secondhand late model deep sump is the way to go.
With a spacer or deep sump some of the additional depth can be used to lower the oil level and keep it away from the spinning crankshaft, and this is good too.
The problem with auxiliary oil tanks is they dont actually add much to the oil in circulation as the hot thin oil just goes straight to the outlet in a concentrated stream and the cold oil remains stuck to the side of the tank. That is why your GS sump has the fins on the inside, not the outside - BMW were late to the party!
If you only use the bike for gentle road use in temperate climates and use a decent Ester Synth the stock system is only just adequate, to remove the cooler without any other changes would be just plain dumb.

 

[(RIP) Arkwright]

 

[Rob Farmer]

If you want some evidence that the oil cooler works quite well. I messed around with a thermal imaging camera a few years ago when I was trying to decide if it was worth taking the cooler off my PD or not. The coolers work well.

As beemerboff mentions above if you take the cooler off fit a bigger sump.

i took the cooler off my other airhead gs and fitted a sump from an 81-84 to increase the oil capacity.

 

[Voyager]

I messed around with a thermal imaging camera a few years ago.

Your front brake has been getting a bit of use, Rob .

Bob.

 

[N. Ohomo]

Interesting. I recognize the above "Off The Road" cooler from lurking Advrider (Beam(st)er). That and a Siebenrock sump spacer could be a satisfying install. Somebody else on Adv. (Prutser) posted a heat sink install, maybe something will develop there as well. Scratch any homebrew aux. oil tank nonsense.
Rob Farmer, that picture is worth a thousand words. Thank you.

 

[Rob Farmer]

Your front brake has been getting a bit of use, Rob .

Bob.

The ti camera highlighted the warping problem when the cast disk got hot. You can see the heat on the warped edge behind the fork leg. Really useful piece of kit.

 

[N. Ohomo]

MAC deep pan

Looks like I'm all over the road here, please bear with me. I just came across the big MAC deep pan @ Niche Cycle Supply. Calls for fitment 1970-1989. Does anybody know why it wouldn't fit 1991 R100GS? Should I start a new thread?

 

[Rob Farmer]

That should fit your gs. You'll need an extension for the oil scavenger. Some of the sump extension manufacturers sell them as a pair - siebenrock link here showing the extension http://shop.siebenrock.com/Engine/Oil-pan:::1_11.html

 

[Beemerboff]

Boxxerparts are giving 10% off until the 27 th, and their kit includes the gaskets. Discount code is KEC360BX
https://www.boxxerparts.de/index.php?cat=c12_Engine.html&page=2