4corsa Posted August 6, 2020 Posted August 6, 2020 I've installed temperature gauge oil dipsticks from MG Cycle (German made) on both my '03 V11 Le Mans and my '07 Ducati Monster S4R 998 Testastretta (liquid cooled). The typical running oil temp range on the Ducati is 85 - 90°C (185 - 194°F), while the range for the Guzzi is 100 - 110°C (212 - 230°F), riding on an 80°F day on both open roads and in town with traffic lights. Is this much of a operating temp difference normal between liquid and air-cooled engines? Are air-cooled engines designed to safely run that much hotter than liquid cooled engines? The red zone on the gauge starts at 120°C, which I've never hit on the V11. But is constant running between 100 - 110°C normal and ok for our V11s? Any shared knowledge on this would be greatly appreciated. 2
Nihontochicken Posted August 6, 2020 Posted August 6, 2020 Can't answer the question, but I have a similar concern. When I take my Suzuki DR650 around town (air cooled single, essentially one-half of a V11, Japanese style), on return checking the oil cooler shows that it's barely warm. The same trip on my V11 and the oil cooler is damned hot, maybe not to boiling water, but too hot to touch beyond a fraction of a second. A major diff between the two scooters. Is one too hot, or one too cold, or are they both just right for their particular engineering aims? 2
al_roethlisberger Posted August 6, 2020 Posted August 6, 2020 I don't know either, but my 1989 air cooled FJ1200 always seemed to be cooler running than the V11...
Lucky Phil Posted August 7, 2020 Posted August 7, 2020 8 hours ago, 4corsa said: I've installed temperature gauge oil dipsticks from MG Cycle (German made) on both my '03 V11 Le Mans and my '07 Ducati Monster S4R 998 Testastretta (liquid cooled). The typical running oil temp range on the Ducati is 85 - 90°C (185 - 194°F), while the range for the Guzzi is 100 - 110°C (212 - 230°F), riding on an 80°F day on both open roads and in town with traffic lights. Is this much of a operating temp difference normal between liquid and air-cooled engines? Are air-cooled engines designed to safely run that much hotter than liquid cooled engines? The red zone on the gauge starts at 120°C, which I've never hit on the V11. But is constant running between 100 - 110°C normal and ok for our V11s? Any shared knowledge on this would be greatly appreciated. Its a combination of many things but its mainly the difference between air and liquid cooling. Liquid cooling is a far superior and more stable way to cool an IC engine and that translates to less engine temp variability and lower oil temps. An air cooled engine relies to a much greater degree on the oil to assist with the cooling. Liquid cooling also has a greater reserve capacity than air cooling which has none as it takes exponentially more energy to heat water the hotter it gets so the system copes with changing conditions better. It has elasticity to an extent. 100-110 is well within the capabilities of a modern oil esp a full group 4 synthetic which you should be using these days. Ciao 5
GuzziMoto Posted August 7, 2020 Posted August 7, 2020 Yeah, liquid cooling tends to be more consistent. That said, I always want my oil temp to get above 212 degrees F so it boils off any water / condensation. 230 degrees F is no issue for decent quality oil. And an oil temp between 212 degrees F and 230 degrees F is what I want. You can install an oil cooler thermostatic valve that diverts oil from the oil cooler until it is up to temp. And you can combine that with a larger oil cooler to gain additional cooling capacity. That should allow more consistent oil temps with a slightly lower max temp while still getting above the 212 degree F target. But personally we don't ride in city traffic and don't have temp issues very often on our Guzzi's. 2
Lucky Phil Posted August 7, 2020 Posted August 7, 2020 3 minutes ago, GuzziMoto said: Yeah, liquid cooling tends to be more consistent. That said, I always want my oil temp to get above 212 degrees F so it boils off any water / condensation. 230 degrees F is no issue for decent quality oil. And an oil temp between 212 degrees F and 230 degrees F is what I want. You can install an oil cooler thermostatic valve that diverts oil from the oil cooler until it is up to temp. And you can combine that with a larger oil cooler to gain additional cooling capacity. That should allow more consistent oil temps with a slightly lower max temp while still getting above the 212 degree F target. But personally we don't ride in city traffic and don't have temp issues very often on our Guzzi's. The V11 has this standard but the Griso doesn't which seems odd but there you go. Ciao 1
LowRyter Posted August 7, 2020 Posted August 7, 2020 7 hours ago, Lucky Phil said: The V11 has this standard but the Griso doesn't which seems odd but there you go. Ciao That might explain why my buddy Darren's Stelvio always had mayo in the valve covers. He replaced it with a Griso after he clouted a deer. Then he clouted a deer with his Griso. That one wasn't totaled and is the quickest Guzzi I've ridden. But I guess he'll still have mayo. It gets hot as hell here and he rides 25 miles to work.
GuzziMoto Posted August 7, 2020 Posted August 7, 2020 Yeah, the Griso's and other CARC Guzzi's definitely have an issue with over-cooling the oil. I did not know (or had forgot) that the V11 had a thermostat stock. Then all you should need is a larger oil cooler. And somewhere to mount it. Or just don't ride it in city traffic. That is what I do.
po18guy Posted August 7, 2020 Posted August 7, 2020 On 8/6/2020 at 10:13 AM, docc said: Perfect for cooking off the moisture! Consistent readings within a narrow acceptable range are a very good sign. I have wondered if I should mount a pair of 12V CPU fans in front of the oil cooler, but no apparent need. As to the difference between the Ducati and Guzzi gauges, one would first have to dip them both simultaneously in a liquid of known temperature to avoid the apples and oranges conundrum. If the gauges verify each other, then maybe the Ducati is intended to run cooler, or it may have a malfunctioning thermostat. As it is with our bodies, i.e. blood sugar, alkaline/base balance etc., too hot or too cool are both detrimental to our health. A little testing and consultation of normal op temps would be in order. As well, German made goods have their variations in quality control as well. Is one gauge an anomaly? One way to find out. 1
4corsa Posted August 7, 2020 Author Posted August 7, 2020 ...all of my water cooled bikes over the years typically run in the 180-190°F range (Ducatis, Triumph Daytona, Honda VFRs, etc). When stuck in traffic on a hot day I've seen the temps go as high as 220°F at which point the fans kick in. Same with friends' water cooled bikes, so I don't think this range can be considered too cold. Since the V11 doesn't have a temp read-out, I decided to get the oil temp dipstick. I will do as you recommend, and put them both in some hot water and see that they are calibrated equally. But again, my main reason for my original post is to ensure these higher temp readings on the Guzzi are normal and not doing any damage.
po18guy Posted August 7, 2020 Posted August 7, 2020 The use of a high quality synthetic oil will also help ease any worries. It is not as affected by heat as even the best of mineral oils. It is specifically formulated for the higher running temps of so-called modern engines, particularly turbo engines which can be extremely hard on any oil. Synthetic evaporates less. Many engines, particularly air-cooled, that are considered to be oil burners are actually running hot enough that a fair percentage of the lost oil has evaporated. This is from the higher heat level and has the vaporized oil has simply been sucked into the intake via crankcase ventilation and burned, rather than by-passing the rings, as is often thought. 2
4corsa Posted August 7, 2020 Author Posted August 7, 2020 I agree, I'm not really worried about the oil performance. What I am concerned about is a repeat of what happened to my first air-cooled bike - a '95 Ducati 900SS/SP. Many years ago on an 85° day I was leaving Port Jefferson shortly after the ferry arrived and was stuck behind 50 cars and a series of 4 or 5 stop lights. 10 minutes later when we finally got through the last light and got moving, my buddy pulls along side of me and starts pointing at the back of my bike. We pull over and he tells me I have blue smoke coming out of one of my exhausts. Long story short, turns out that the rear aluminum cylinder (the rear always runs hotter on Ducatis due to less ventilation) warped due to overheating. The bore became slightly ovalized which allowed oil to bypass at the two new long ends of the oval. The '95 and earlier 900SS did not have an oil gauge and the overheating warning light never came on. I have no idea what the oil temp got to that day. So, I'm more concerned about the heat causing warpage than the oil breaking down. 2
Lucky Phil Posted August 8, 2020 Posted August 8, 2020 2 hours ago, 4corsa said: I agree, I'm not really worried about the oil performance. What I am concerned about is a repeat of what happened to my first air-cooled bike - a '95 Ducati 900SS/SP. Many years ago on an 85° day I was leaving Port Jefferson shortly after the ferry arrived and was stuck behind 50 cars and a series of 4 or 5 stop lights. 10 minutes later when we finally got through the last light and got moving, my buddy pulls along side of me and starts pointing at the back of my bike. We pull over and he tells me I have blue smoke coming out of one of my exhausts. Long story short, turns out that the rear aluminum cylinder (the rear always runs hotter on Ducatis due to less ventilation) warped due to overheating. The bore became slightly ovalized which allowed oil to bypass at the two new long ends of the oval. The '95 and earlier 900SS did not have an oil gauge and the overheating warning light never came on. I have no idea what the oil temp got to that day. So, I'm more concerned about the heat causing warpage than the oil breaking down. You know without knowing all the details here I doubt the traffic heat did your Ducati any real harm. I say this with confidence because in my race track experience I've never seen any engine that can cope with temperature abuse like a Ducati twin. I once saw an 851 superbike back in the day run completely out of coolant during a race and arrived in the pits with the cooling hose fittings (plastic in those days) melted off. Result? fit new coolant fittings and rectify the leak and back out for the next race with no issues. I've seen another rider with a bike I know well sit at the end of pit lane idling the race bike until it boiled and started dumping fluid on several occasions and away it went without problems and was fine when pulled down. The rider had to be re educated to NOT head out as soon as pit lane opened and cruise down to the end and sit there and wait for the green flag. He was a owner/rider but didn't work on the bike and had zero mechanical skills or knowledge but he had deep pockets which made education on mechanical sympathy difficult. I remember a delayed WSB race once in Italy when it was very hot and Troy Bayliss came back to his bike on pole position after going for a quick toilet break before the delayed start and gesticulating to his mechanic and pointing at the dash and the mechanic shrugging. Troy gave him the old Aussie "Arr @#!#$# it wave off" and the race got going and he won. I knew what he was gesticulating at........engine temp. It had overheated on the grid. Didn't matter though, still won. There'r heat tough Ducati twins. Mechanically a bit fragile in those days but temp tough. Ciao 1
pete roper Posted August 8, 2020 Posted August 8, 2020 Don't be. Apart from anything else it should be remembered that the original big block motor was designed to sit idling in Milan traffic in high summer with a fat Carribinieri sitting on top of it! Just about the only relevant changes to the design are the adoption of fuel injection and, with the advent of the Squarefin motor, even greater fin area. A thermostatically controlled oil cooler is a benefit but more so the faster one is travelling. At slow speed or a standstill the difference it makes is marginal. Yes, modern engines run hotter but in all my years of working on them I've never seen problems caused by overheating as long as the lubrication system is working as it should. The Nuovo Hi-Cam motors as used on the CARC series bike do have an issue due to the sump spacer gasket blowing out on the lubrication side. This results in a loss of pressure which can cause damage but such a failure usually makes itself known by the camchains starting to rattle as the hydraulic tensioner plungers are starved of oil. It has caused big end failures but is fairly rare, (Although I replace the gasket as a matter of course during rollerisation of an 8V. There is a very much superior aftermarket gasket available that completely eradicates the problem.) just something to be aware of. It is NOT something I've ever known to affect any of the 2V motors. As for heat? My Griso in high summer will heat its oil to >135ºC in traffic. It's never caused me a problem. Conversely I worry more in winter as it's damn near impossible to get the oil above 75-80ºC due to the cooling circuit not being thermostatically controlled. Yes. Try to avoid getting stuck in traffic for hours in high summer but I wouldn't die in a ditch over it. The excessive heat is far more likely to cook the phase sensor than cause metallurgical or lubrication problems. 4
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now