Oil temps, how hot are you running?

weekendrider

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From Dogbunnys classified ad I see there are lots of folks running his excellent replacement dipstick. A few are posting running temps.
I was hoping a few more would post what temps they are seeing.
The varibles are going to be many, and I haven't found any 2 650's that run exactly the same. I think Will has found the same with his testing.
What temps are you seeing?
In what conditions?
And what do you think are the causes of the high temps?
Myself, as the weather warms to the high 80's with moderate to high humidity,
am seeing a top temp of 285, almost pegged out.
Unlike some my temps rise at the lights after a 30 mile 4.5-5K ride.
Cruising I am seeing 255-270.

Thanks to the perfect indexing I can check it as I pass under the street lamps after midnight. Ambient temps run 20-30 degrees cooler on the return trip. But under the last lamp I am still seeing close to 220.

Dogbunny I will post the comparision between the candy thermometer and your piece later(tomorrow). Also will pull the plugs to check lean condition.
 
I have seen people report a wide range of temps. I have an RR brand (German) gauge, which reads in Celsius, but I have seen around 100 at the cooler end (in cooler weather) to 120-ish in high mid-Atlantic summer... roughly 200F to mid 240sF, I'd say. The few times I have had the bike out this past winter, I was experimenting with 10W-40 full synth, and the bike seems to like it, so we'll go to 20W-50 full synth for the spring and summer, and see how we do.

TC
 
With the cooler spring temps of 60 to 70, I'm seeing about 200 to 220. Last summer when in the 80s, I was seeing about 250.
 
Just came across this thread searching for temps. I was worried that my 200 degrees was too much on a pretty warm day here. Seems like I'm doing ok. Thanks guys
 
That seems to be the norm. Ya'll aren't even boiling off condensation:wink2:
I am still seeing 270-280 at the last lights into work.
I've upped the main to a 137.5 with no change in the temps.
A comparision of different thermometers says Dogbunny's is telling truth.
Now I need to drop the thermometer in another bike 2 see what condition my condition is in.
 
I own a few well-running XS650s, and I have been trying to get a better handle on why they operate at different temps as measured by my ThermoDipSticks. Following are some ideas:

A lean-running engine runs hotter than a rich-running engine. This is well-documented and accepted.

The further advanced the timing, the hotter the engine runs. Also well-documented and accepted. Here is a chart:
http://www.procarcare.com/images/shar/encyclopedia/8852VG01.gif

The higher the compression of the motor, the hotter the engine runs. This is just a personal theory, but it is based on the Ideal Gas Law which says that as you compress a gas, its temp rises. A higher compression motor compresses gas (the air/fuel mixture) more, so logic says it creates more heat. Also, friction at the rings is involved -- an engine with better compression achieves that better compression by a tighter fit at the rings, which creates more friction as the piston cycles, which creates more heat.

The thicker the engine oil, the hotter the engine runs. I'm not so sure about this one. Does thicker oil mean the parts don't move so freely, so there is more friction and thus more heat? Or does thicker oil mean more metal-on-metal protection, and thus less friction?

weekendrider, I have talked to you about your temps before, and I think you are running hot. I believe that when the sump temp hits 260 as measured by a ThermoDipStick, you should become concerned. Since you have already tried going richer, I would look at your timing. If you can't get your temps to come down, I would consider installing an oil cooler.
 
Had to come back to post I was running about 250-260 with the temps outside today well over 90 and stuck in god awful traffic. Between the heat outside and coming off the bike it did not make for a pleasant ride today.
 
I thought I would resurrect this thread. I am in the prcoess of dialling in carbs on my Bobber build. I have Dogbunnys dipstick and I am running in the 230s and 240s, which I know is lean and hot. So, I am curious to find out whato others are running??
 
1979 XS650......I am running the XS Performance oil filter/cooler combo.....but I doubt this makes a huge impact.

Oil%20filter_cooler.jpg


Anywho....did alot of riding in the upper 60 degree days at the beginning of the season....was seeing about 220 to 230.

Figured that if it was 100 degrees out Id see a fairly big increase in temps....so I was slightly worried.

However recently had an early record setting day and rode alot on a sunny 95 degree day.......just barely got to 235 degrees going down the road.
 
I am running the XS Performance oil filter/cooler combo.....but I doubt this makes a huge impact.

I remember somebody tested temps with it and decided it made no impact at all...

I used a thermometer a couple of times a couple of years ago and was about off the scale. Not really, but higher than any other xs650. But a few days ago I checked my compression and it's 150 - the same at 60,000 miles as it was at 17,000.

I think your temperature by itself is nothing to be concerned about until you hit the melting point of aluminum :) :)

Shortened life is going to be a function of how much you jerk it around, like with any other vehicle. Including how much you use a grinder on it...
 
http://www.xs650.com/forum/showthread.php?t=14997
Paulrxs650, The above thread is long and contains a lot of running temperature info. You didn't mention anything about ambient temperature, however, I do suspect that you are running just a bit hot and lean. But, as xjwmx is implying, you probably aren't damaging anything as long as the over-all health of your bike seems okay. I have done some riding on a hack-job re-build that is definitely screwed up, I get temps of 250 in the same conditions that my other bikes would be registering 210. When you have an engine as screwed up as that one is, there will be other signs that something is seriously wrong -- in this case, when hot, the engine hunts, it weeps a lot of oil, and it becomes difficult to find neutral.

aaronkelly, I agree that your filter/cooler has a negligible effect on oil temps. I think that I relate a before and after temp comparison in the thread I cited above. Otherwise, that filter/cooler is a great product made by a great company, Heiden Tuning in Holland, and last time I checked it was actually cheaper to get it shipped directly from Heiden than it is to buy from MikesXS.
Heiden makes some other interesting engine accessories. I bought this one:
http://www.xs650.biz/p/28/3426/mo74-cg|22=3/#ht-0091-cooler-adapter-for-oil-delivery-pipe
and again, I think the difference that it makes is negligible, although the cooling happens where it is most needed -- right before the oil enters the head, so even a couple of degrees cooling at that point is a good thing.

The absolute best way to compare engine temps is side-by-side in two bikes, both with ThermoDipSticks. A little over a year ago I lent a ThermoDipStick to xjwmx, and we rode side-by-side along with a third ThermoDipStick-equipped bike. As I recall, xjwmx's bike is pretty much all stock and completely unmolested with regards to carbs, engine, intake and exhaust. As I recall, his BS34s have stock jetting, and the mix screw plugs are intact, meaning that he has never altered the factory mix screw setting. 5twins and other carb gurus maintain that the BS34s as delivered from the factory were slightly lean. I think this was born out in xjwmx's ThermoDipStick readings, which were consistently about 20 degrees higher than the other two bikes. However, the bottom line is the over-all health of the engine, and xjwmx's seems fine. I will add that xjwmx is a conservative rider, he does not "jerk around" his bike, and I think that is the real secret to long engine life.
 
I have two bikes, the 75 has the 750 kit as well as headwork, mild cleanup on the ports. Uni Filters, home made headers, Emgo Shorty megaphone mufflers. The other is an almost bone stock 81. The air filters in the 81 were falling apart. I replaced the crappy stock element with foam from a garden traxctor air filter.
Under simular conditions they run within about 20 degrees or less difference. I use the same thermo dipstick in each bike for comparsion. Ride one, swap dipsticks ride the other. On a 75 degree day they run around 220 to 240. A bit warmer if I run at higher speeds. Like 75 to 80.
I adapted a side cover so I could add a external oil filter and a cooler. All the oil went through the cooler.
I had the results of my testing somewhere, can't find them right at the moment, but as I recall just the oil filter gave about a 5 degree drop in oil temps. Add the cooler it dropped around 45 degrees more. A total of about 50 degrees. Around 170-180 degrees oil temps. Almost too much cooling, barely warm enough to boil out contaminents in the oil.
One thing it did do was when checking cylinder and head temps with a noncontact thermometer the temps dropped around the same amount, 50 degrees, as the oil temps. It also evened out the right to left head/cylinder temps.
Before I did the oil cooler mods the engine ran about 15-20 degrees hotter on the right side. With the cooler the difference dropped to less than 5 degrees.
Leo
 
The main things that determine the engine/oil temp are the air temperature and the amount of air flow over the engine cooling fins. If you live in southern half of USA, mexico, central america,tropical australia etc., then you want to have an oil cooler on your bike. If you often sit in traffic, with no air flow, then an oil cooler is wise as well.

Knowing the actual temperature by watching a thermometer is of little to no value. The real time temperature will vary up and down, as the above two factors change.

No need for an oil cooler in Canada:)
 
http://www.xs650.com/forum/showthread.php?t=14997
As I recall, his BS34s have stock jetting, and the mix screw plugs are intact, meaning that he has never altered the factory mix screw setting. 5twins and other carb gurus maintain that the BS34s as delivered from the factory were slightly lean. I think this was born out in xjwmx's ThermoDipStick readings, which were consistently about 20 degrees higher than the other two bikes.

It's easy to attribute the extra heat to leanness but it could have been oil, oil level, etc., or just a tighter engine. As you know, I'm not convinced it was leaner, much less that the leanness was the cause of the extra heat. I've found you can go from lean popping to rich black smoke just by changing the float level a smidge. Suits my purposes just as well as any other method.


However, the bottom line is the over-all health of the engine, and xjwmx's seems fine. I will add that xjwmx is a conservative rider, he does not "jerk around" his bike, and I think that is the real secret to long engine life.

I don't burn rubber accelerating, which is what I meant by jerking it around. I might ride for four hrs at 70-80 mph, but I don't try to get there instantly. Austin thinks I'm conservative because I let the stoned 20-somethings go way ahead. :) I'm sightseeing and I don't want to miss seeing the aftermath :) Plus when you ride everywhere you better hedge your bet with a little conservatism :)
 
For what it is worth. I haven't been able to reduce the temps by rejetting(yet).
I still am seeing 260-270 degrees at the end of a regular commute.
I have removed the tool bag off the front forks. But added the windshield(for awhile).
Yesterday a round trip(70 miles) on the same road, same speeds got me 220-230 going and 260-270 coming home.
The difference? A steady 15-20 mph head wind when going.
So many variables . . . . . . . . .
 
Yes, leanness is not the only cause of high heat. It's been a while since I thought about what I wrote in post #7 in this thread. Other causes of high heat are advanced timing -- this is well documented -- and possibly oil viscosity and engine compression.
 
Yes, it wouldn't surprise me if guys running that 15W40 diesel oil get higher temps than guys running 20W50. I stopped using it because the top end clattered more than with the 50W.
 
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