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Cooling Oil Circuit Thermostat.

That's what I was thinking. The company that made it went defunct years ago, so I'm pretty much on my own trying to sort it out. There's a circlip retaining a recessed cap, which is where it's leaking from. I guess I need to pull that and see what's going on inside.

__Jason
 
Most likely an O-Ring on the Cap/Plug part.
Pop the Circlip and take a look.

O-rings can be ordered by size, you'll just need to measure the Outer Diameter (O/D), and the Cross Section (thickness) of the ring.
Double check by measuring the Bore it's in, and the diameter of it's groove.
 
Hey y’all! I just got the thermostat to get this project going on my Stelvio. Could either of you give some more details on how you mounted it? I’m hoping for upfront like @John Warner, but am open to mounting it on the side like @boscoman.

Thank you in advance for any help!
 
For such a large Bike, there's not actually much 'spare' room on the Stelvio for mounting stuff.
With all the different Hose Fittings available, you could fit it just about anywhere you wanted, within reason.
 
For such a large Bike, there's not actually much 'spare' room on the Stelvio for mounting stuff.
With all the different Hose Fittings available, you could fit it just about anywhere you wanted, within reason.
Yeah, that’s what I’m noticing! :D

Do you have any advice on how to fasten the thermostat? I was thinking of drilling holes in the alternator cover and using small bolts and nuts to attach it there (if there is enough room behind it for the bolt heads).

Boscoman’s location is cool too. Did he just use some sort of epoxy?
 
I do. I thought you were a busy guy. Don’t go down this rabbit hole train wreck. ;)
Uh-oh!

Once I find the best place to mount the thermostat, there is a really great shop here that specializes in oil lines for race cars that will set up all the lines and fittings for only about $100. Should be pretty straight forward? Maybe not?

I am a busy guy, but this bike is my primary hobby right now, so I have some time to devote. :p

Scott - How does your Stelvio handle the Ohio winters? I intend to ride as much as possible in these cold temps.
 
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Please forgive me but this seems like a great deal of complexity and headache for something that isn’t necessary, let alone it creates yet another major point of failure down the road in terms of all of the seals and connections.

If the motorcycle is ridden for a sufficient time where it can reach and sustain an operating temperature for 30 minutes, then it makes this really questionable at best in my mind.

I have to agree with GTM on this one.

My Stelvio runs perfect anytime I use it. It has the GTM Full Fueling modifications setup of the PowerCommander and Autotune dual O2 sensor setup.

However, for most winter activities, I utilize my Ural Gear Up. It’s insanely stable and on demand 2WD is impossible to beat.
 
Thank you both for your thoughts!

From what I've been reading, the 1200 8V motors don't reach the proper operating temperature when it's under 45ºF outside, which is what inspired the various thermostat projects I've seen.

On the point about complexity, there is a high quality oil thermostat available for sale (I am not capable enough to make my own like John :D ). The rest is pretty standard oil lines and fittings.

I have the thermostat in hand, but now I'll have to reconsider. 🙏
 
From what I've been reading, the 1200 8V motors don't reach the proper operating temperature when it's under 45ºF outside
As a counter-point, there are many high-mile all climate 8Vs that have lived hard lives, and they are still all running strong. The factory has four seasons where the bikes are developed.
Case in point is my friend Andrea, who is part of the new Stelvio release. He bought his new, and literally rode it around the world.
I’m not trying to make anyone wrong here, but I personally think it’s a waste of time and $.
 
Any motorcycle engine, run continuously for 30 minutes, reaches a normal operating temperature inside the crankcase regardless of the ambient air temperature. Guaranteed.

I have friends in and around Mandello del Lario and Switzerland. They ride almost year round and quite extensively in the Alps.

To my knowledge, none of them have ever had any issues which would cause them to want to make this major modification to their Stelvios.

I too, don’t want to pee on the parade, but I am grasping at straws here in trying to understand the reasoning for doing this.

With regard to “milkshake” inside the valve covers, it has been my experience that this is caused more by rain, and the sudden rapid cooling of the engine in the presence of moisture saturated air. This becomes especially apparent when people take a hot motorcycle to a self-service car wash, and then blast the engine case with cold high pressure water.

It is my belief that any moisture in the air in the crankcase and valve train, will form water condensation on the walls of the inside of the valve covers and engine case. At the next running of the engine for a sufficient duration, the moisture will heat and convert to a gas and be blown out the crankcase vent system.

YMMV.

I wish you the very best whichever way you decide to go here.
 
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