Ducati Multistretta 1098S

[Taipan]

A lot of ECU remaps lower the temp that the fan kicks in fan at, and on my 690ktm i replaced the fan sensor with one that brought in the fan earlier. So if the software, or different fan sensor, can adjust the fan kick in temps, could you not do that and fit the oem rad? Would that help with a higher running temp and the safety net of the fan kicking in sooner?

[Mr. Dazzle]

Do "they" not make different temp thermostats anyway? I'd have guessed a bike with as many racing versions as the 1098 has multiple thermostat options?

[millemille]

A lot of ECU remaps lower the temp that the fan kicks in fan at, and on my 690ktm i replaced the fan sensor with one that brought in the fan earlier. So if the software, or different fan sensor, can adjust the fan kick in temps, could you not do that and fit the oem rad? Would that help with a higher running temp and the safety net of the fan kicking in sooner?

I had given the idea of an OEM radiator some thought but there's a couple of problems with that. One, the bodywork is designed and modified to work with the Aprilia radiator. So to fir the Ducati OEM rad requires a second set of bodywork. Two, when it's really hot the OEM radiator isn't up to the job. The internet abounds with stories of 1098 owners sitting in traffic in California with the fans running flat out and coolant pissing out of the overflow and the dash flashing warnings of impending mechanical doom if the engine isn't turned off.

[millemille]

Do "they" not make different temp thermostats anyway? I'd have guessed a bike with as many racing versions as the 1098 has multiple thermostat options?

Nope, all the road bikes - including the cooking versions raced in superstock - have the same thermostat part number. Your full monty race bikes don't run a thermostat.

[mangocrazy]

Is the OEM 1098 thermostat effectively a sealed unit, or is it a housing with a stat that drops in? If it's the latter you might be able to drop in a hot climate stat from a different bike. Have you checked part numbers on bikes for different geographies, such as northern Australia?

[millemille]

Is the OEM 1098 thermostat effectively a sealed unit, or is it a housing with a stat that drops in? If it's the latter you might be able to drop in a hot climate stat from a different bike. Have you checked part numbers on bikes for different geographies, such as northern Australia?

Sealed unit

[millemille]

If it's the latter you might be able to drop in a hot climate stat from a different bike. Have you checked part numbers on bikes for different geographies, such as northern Australia?

I'm struggling a bit with this one, why would the thermostat be different in operating temperature range for different geographic markets?

There's only one part number for the 1098 thermostat worldwide as far as I can see, but irrespective of that, why would you want a different stat if you lived somewhere warmer and why would that help my issue?

[mangocrazy]

In the car world you can obtain hot climate, temperate climate (us) and cold climate thermostats, all of which open and close at different temps. The hot climate stat I run on my Beta Spider opens at 74 degrees C, whereas the standard temperate stat opens at 82 deg C if I remember correctly. It means that the cooling circuit is operational 8 degrees lower than on a standard one and cools more effectively, at a lower start temperature and for longer, which is what you want n'est ce pas?

You can also obtain radiator fan switches that switch the fan on at a lower temp than standard. It's all about not giving the heat a chance to build up and overwhelm the cooling system.

[Taipan]

Years ago (early 90s) when I was towing a caravan to Spain a lot of caravanners used to advise changing the thermostat for a colder opening one. Pretty common practice back then..

[millemille]

It means that the cooling circuit is operational 8 degrees lower than on a standard one and cools more effectively, at a lower start temperature and for longer, which is what you want n'est ce pas?

No, I want the opposite. It is cooling too well currently, the thermostat is fully open before the coolant temp trim table has backed off. I want a thermostat that isn't fully open until after the coolant temp trim table has backed off, which is what the KTM 390 one is supposed to do (opening fully by 90 degrees)....

[mangocrazy]

Ah, OK. In that case you want a cold climate stat. They don't open until around 90 degrees C. Sounds like the KTM 390 one is what you need. Is there a problem with getting hold of one?

But if the opening of the thermostat is controlled via a map/trim table, isn't it possible to do it that way?

Apologies if this is going over ground already covered. I just replied based on the last few posts.

[millemille]

Ah, OK. In that case you want a cold climate stat. They don't open until around 90 degrees C. Sounds like the KTM 390 one is what you need. Is there a problem with getting hold of one?

I've already ordered one as they're only £30, need to take a look at the hose fitting sizes when it arrives as they may be different to the Ducati one, but that's based on looking at photographs online and the KTM parts fiche (KTM parts fiche shows the hose clamps on all three hose fittings on the KTM thermostat body as being the same part number, so presumably the same size, but the Ducati thermostat has two the same size and one, the return back to the radiator, a larger size).

But if the opening of the thermostat is controlled via a map/trim table, isn't it possible to do it that way?

Apologies if this is going over ground already covered. I just replied based on the last few posts.

The thermostat opening is controlled in the old fashioned, purely mechanical, way. No interface with the ECU whatsoever.

[millemille]

Quick update. KTM thermostat arrived and, as suspected, it's similar but not identical to the Ducati one.

The two inlets are the same diameter as the Ducati one, but about 10mm further apart, which made fitting it an absolute monster of a job.

The outlet is 22mm diameter, as opposed to the Ducati's 28mm. I've ordered the only 28mm to 22mm silicon hose reducer I can find, but I don't think it'll fit*. I just want to mackle something up that allows me to test the new thermostat and any improvement in the running temperature, so maybe even cutting a ring of 22mm silicon hose and using it over the outlet to clamp the 28mm hose on to might be good enough.

If the KTM 'stat does the job then I'll look at getting a one off hose made.

*What I think will work is a 45 degree 28 to 22mm black silicon hose reducer, one of these..

https://www.autosiliconehoses.com/silic ... e-red.html

..but 28 to 22, which I can't find anyone making?

[millemille]

An update after a day of lows and highs...

Multiple trips to Austria and Germany for work, a week in Spain on holiday and a dose of the COVID meant little has been done on the Ducati since the last post until this last week.

As suspected, the KTM thermostat had a smaller outlet than the OEM Ducati one. This necessitated mackling up a bit of an abortion of hose adaptors and joining pieces and loads of Oetiker clamps to get it plumbed in and fitting...



...as I didn't want to make any permanent modification to the existing cooling pipework in case the KTM 'stat didn't do the job.

And then when I filled the cooling system the fitting on the rear cylinder head (the back plastic 90° elbow in the photo)..



...started weeping, because the KTM stat was different enough to the Ducati one to be trying to lift the fitting away from the head.

On the off chance, more than anything else, I stripped it all down and removed the elbow and checked the condition of the square section o-ring that seals the elbow to the head. Luckily I had a spare brand new one, so when the old one measured up 1.5mm thinner than the new one I chucked the new one in and bolted it all back and filled the system and it was no longer leaking.

Another issue I've been wanting to look at is the side stand. The standard multi stand is known, even on bog standard bikes, for letting the bike lean over a long way. And with my bike running a lot more ride height it was even worse. This picture gives some idea of how much lean there is with the OEM stand, when you look at the angle between the bike and the level ground in front...



There's a guy on the multistrada forum who's been using a modified panigale side stand for a year or so, subjecting it to all kinds of use and abuse with no issues, which isn't actually any longer but doesn't stick out at such an angle so it makes the bike sit more upright due to effectively being longer. Anyway, he offered up another one for sale on forum so I bought it off him to try.





There isn't any flat ground where I live, so if isn't obvious that the bike is now a lot more upright then you'll just have to take my word for it .

With an MOT booked for this morning the last week has been spent getting all the last little bits and pieces and done and checking tyre pressures and chain slack and the like.

All boxed up and done last night, with the bike starting and warming up like a dream and my lucky jubilee clip fitted....



,...and the plan was to give the bike a wash this morning and then get booted and suited and head over to Derby for the MOT and then a couple of hours of rumbling about the Peaks, taking advantage of the weather and taking the opportunity to get back into the groove not having ridden it for two years.....

That was the plan.

Bike washed.



Booted and suited. Bike would not start. Throwing immobilizer fault codes.

After some googling of the fault code and some investigation it turns out the immobilizer antenna, which clips to the underside of the ignition barrel cover....



...had become dislodged, probably thanks to overenthusiastic spraying of the hose around the headstock by yours truly while washing the bike, and dropped down by a mm or so. This was enough to stop it detecting the key's transponder chip. So refitted and a couple of drops of superglue applied to hold it in place securely and all boxed up and it was back to starting on the button.

Problem was I'd now missed my booked appointment and couldn't find anywhere else open or that had an appointment available.

Fuck it.

I took it for a local test ride anyway.

Good news, the coolant temperature is now where it is supposed to be. Running at 75° while trundling along, whereas it would have been at about 55° on the Ducati thermostat.

Even better news, the bike is as much of a hooligan toy as I remember it being before it was taken off the road two years ago.

So, disappointed to have lost out on any riding this weekend but over the moon that all the issues that causes it to be taken off the road appear to be solved.

I'm away with work until Friday so I'll see if I can get it in for an MOT first thing Friday morning.

[Bigyin]

Glad you got everything sorted and you have the patience of a saint to produce such a superb bike ....i have the same engine so i know what stupid grins they can induce

I'm guessing the lucky jubilee clip is the same as the lucky gaffa tape strip i used to have on my Akra on the zx636 that may have covered the "race use only" stamp on the can

[millemille]

MOT passed with no problems.

Took it for a spin around Derby to shake it down, which was a good job as I ended up sitting in a cloud of steam as the mackled together hose setup for the KTM thermostat started leaking.

Luckily I was on my way to visit a mate at the time, so it was a simple matter of nipping up the hose clamps and topping up the coolant.

Ambient air temp was 14° and it was hoofing it down with rain and the coolant temperature was running between 75 and 90 degrees, so very happy with that.

Got a full day out on it planned on Sunday, if all goes well I'll crack on with a permanent hose solution for the thermostat hoses.

[millemille]

Over 200 trouble free miles on a variety of roads in a variety of conditions since getting its MOT last week. No engine bearings shitting itself, running at the correct temperature, starting on the button.

So we can chalk it up, finally, as a win.

Tidied up the thermostat hoses and that's it now, just riding it.

Not ridden a motorbike any meaningful distance for about 18 months so rusty as fuck, but my mojo is coming back.

If anyone finds themselves fancying a Peak District spin, give me a shout...

[weeksy]

Nice job sir.

I'm up for one, but you can fuck off with motors/engines

[Taipan]

I admire your tenacity! Glad you finally got it sorted!

[millemille]

Had to head down to Kidderminster today, thought I'd take the bike.

Headed off this morning at 07.00 in pitch darkness and pissing down rain and 5° temperature with heated grips set to stun

Took the back roads towards Uttoxeter and on to Stafford and the M6. A couple of miles from home and I come across a dip in the road that was full of water with cars very cautiously inching through.

I took my turn, standing on the pegs like the rufty tufty hard core adventure rider that I am not, and was deeper than I expected. A lot. My feet were well under water and the spray was epic!

Through and on my way.

A little while later the heated grip controller was flashing an LED, telling me that battery voltage was dropping. Off and back on again. LED off for a few miles and then back on again. Thinking that maybe water had got in the controller, so carried on turning it off and on again all the way down the M6 and a mile or so along the M5 until....



...it died. Battery not charging. The heated grip controller wasn't lying, the battery voltage was dropping and had in fact....dropped.

Hour and a half wait for a nice man in a yellow van with a very nifty Meccano bike trailer.....



..and I'm back home.

No output from the alternator, it looks like submerging the alternator connector with the bike running isn't a good idea.