Hot Breva

[mg877]

Would appreciate your thoughts on the running temperature for Brevas.
I wonder if I might plumb the depths of your technical knowledge regarding the running temperature for my 850 Breva.
The bike is running really well however, it does seem to be running really hot. The plugs are an OK colour (very light brown) but it takes about an hour for the engine to cool down sufficiently to be able to place my hand on the rocker box covers. I know that these engines are designed to run hot and I'm sure that an:dry: oil cooler will help but, it does seem to be running much hotter than my previous Guzzis.
Is it possible that the engine heat sensor is not functioning as it should, and is there a way to check this?
Appreciate your help.

 

[Holt]

Probably run hotter than the 1100, since there's no oilcooler on the 850.
The 750's runs really hot; I've got 145* C after running fast on motorways, and a normal motor temperature will be at about 130*C summertime.

This calls for a very high quality oil, if you don't want the oil turning into resin.

But as the 850 is a big-block it's probably possible to install an oil-cooler?

 

[guzzibob]

Since the 850 is a big block, it presumably has the standard big block oil capacity, which is about double that of the small blocks (only 1.75 qts, unless you get Guzzitech's sump expander for the small blocks-I wouldn't have a small block without one), so I suspect the 850 can do without the oil cooler-only 100 cc more displacement than the 750's, but like I said double the oil capacity. Anybody know for sure about the oil capacity of the 850's?

 

[Mackers]

I've just bought an 1100 and have been really surprised how hot it runs. Also I'm getting noticeable heat off the heads onto my legs. So the oil cooler isn't having a lot of impact on the outside temperature of the heads and rocker covers. Lovely motor and gearbox though, after having the Stone for the past 4 years.

 

[guzzibob]

All the new bikes throw off much more heat than earlier Guzzis, perhaps a reflection of higher HP output? No doubt also that is why they specify the oils that they now do.

 

[kiwi dave]

My understanding is the increased heat is due to the alternator sucking hot air through the oil cooler and blasting it out on to the rider's legs. As the Griso has its oil cooler on the side, this doesn't happen with this model, and the rider doesn't get the hot air to the same extent as the rider on a Breva or Norge.

Anyone with a Breva and a Griso that can vouch for what I have just speculated?

 

[Holt]

I'd say the heat is probably caused mostly by the lean mixture, due to emission rules.

Adding a sumpspacer to the 750 only lower the engine temperature marginally - about 5* C - but do have other advantages.

 

[guzzibob]

Holt wrote:
Adding a sumpspacer to the 750 only lower the engine temperature marginally - about 5* C - but do have other advantages.[/quote]

I agree 100%. Still wouldn't be without one on a small block. The big advantage is that some of the small blocks burn a bit of oil when new, & the oil capacity is so low that if you are not right on top of it, frequently checking & keeping the oil level up, you have a chance of blowing up your motor/torching the crank. It's happened a number of times, inc on Guzzi demo bikes. I would also assume that eventually when these motors get enough miles on them, like all high mileage motors they will eventually begin to burn a bit of oil-putting you in the same danger as when new. Cost of the spacer is minimal compared to the potential costs, & a one shot deal, other than the minor costs of an occaisional additional sump gasket & the cost of the extra quart or so of oil at each refill-but then, the latter is the point of the whole deal.

 

[mg877]

Thanks guys.
Added an oil cooler but it turns out that the TPS was way out thus causing lean running which = heat.

 

[Holt]

mg877 wrote:

Thanks guys.
Added an oil cooler but it turns out that the TPS was way out thus causing lean running which = heat.

I'm somehow happy to see my theoretical reasoning confirmed. :blink:

 

[GTM®]

Holt wrote:

I'm somehow happy to see my theoretical reasoning confirmed. :blink:

I've witnessed this on the dyno, and used a PC to cool things down and raise the power often up to 17% (with simple modifications). When the new PCV is available hopefully here soon, expect to see much of the same.

 

[vfrhans]

Holt wrote:

I'd say the heat is probably caused mostly by the lean mixture, due to emission rules.

Adding a sumpspacer to the 750 only lower the engine temperature marginally - about 5* C - but do have other advantages.

A word of wisdom, please, for the uninitiated to the Guzzi priesthood. I have seen "deep sump" pans on older airhead BMW's. Is this "sumspacer" anything like that? I ride a 2004 Breva 750 and now you've got me all scared, i.e. not really that scared until things here in U.S. Siberia start thawing out again in April. Who sells these things? How much? How hard is it to install one?
TIA!
Hans in Minneapolis hmy:

 

[Holt]

vfrhans wrote:

Holt wrote:

I'd say the heat is probably caused mostly by the lean mixture, due to emission rules.

Adding a sumpspacer to the 750 only lower the engine temperature marginally - about 5* C - but do have other advantages.

A word of wisdom, please, for the uninitiated to the Guzzi priesthood. I have seen "deep sump" pans on older airhead BMW's. Is this "sumspacer" anything like that? I ride a 2004 Breva 750 and now you've got me all scared, i.e. not really that scared until things here in U.S. Siberia start thawing out again in April. Who sells these things? How much? How hard is it to install one?
TIA!
Hans in Minneapolis hmy:

Since I haven't seen anything but OEM pans on Beemers no wisdom from here.
The small-block spacer is easy to install, and will allow just about 1 US pint or quart or whatever. 0,95 litre it shall be! - extra to the sump; thingy is sold by your honoured host here - or his partner, that is.
Meaning Ed Milich, who also are the inventor, manufacturer and deliverer.

I once put this posting on the other board:

Due to the non-existing service of the local postal service, which practically discontinued itself, the package from Ed Millich was delayed so it would first reach me after leaving to Mandello his September.

But now it´s there, and the mystery of the two drain plugs are also solved ;D

The sumpspacer will increase the amount of oil in the sump to just about 2,7 litres (2,85 us qt).

The season here is nearly over, they are promising us the real fall coming in wednesday this week. Fall will mean hard winds, temperatures way under +10 C (50 F) and hard rains or fog. No cool (!) weather for riding, so I´ll have very limited opportunities for testing what happens to oil temperature. The oil temperature was the main reason for purchasing the spacer.
When driving at about 140-150 kmh (90 mph) on German highways I was measuring oil-temperatures just slightly under a 140 C (280 F), so I guess the increased volume would be helpful...
I still would use very high quality synthetics oils, though.

Motor has now run way over 25000 kms (16000 US miles). Ive been changing oil according to ordinary service interval. I cannot really see any signs of metal chips or any grit or sludge in the sump. Just a dead bug.

Sump off. See the small round plastic filtre? Its the space underneath which would be drained by the front plug.

Motor from underneath. Mentioned temperature-dipstick will be seen.

Spacer on sump.

Sumpspacer on motor. It does not lower much. See next pic. Advantage: I can reach front oil-drain plug without dismounting "belly-pan". (Edit: No I can't)

Only thing worrying me are the new mounting bolts might be a bit too long. It's no worry on the sides of the pan, threading are all the way through, so you can see the top (bottom?) of the bolt. But there are two bolts in front and two in the back which will not be seen. I felt a little to much resistance when bolting on, so I'm not really sure of the right torque. But I'll re-torque after first drive.

Edit: A couple of years later I still have a slight leakage. If & when I pull that sump I do swear I'll shorten those bolts.....

Also; as said, the spacer doesn't lower the temperature much. But it gives some security on the consumption-issue. Also a larger amount will prolong the life length of the motor oil. Of course.

 

[vfrhans]

Now that's what I call an initiation. Thanks, Holt, especially for the pictures!
Hans

 

[guzzibob]

Holt wrote:
The small-block spacer is easy to install, and will allow just about 1 US pint extra to the sump; .[/quote]

Uhh, no. Added capacity is 1-1.25 QUARTS, not a measley 1 pint, per the guzzitech sale point. Just look at the pix, way more than 1 pint worth of space added. Since stock capacity is a lousy 1.75 qts, this is a substantial increase, & really solves/prevents the potential problem it was designed for.

 

[RJVB]

Holt wrote:

Holt, looks like you have some liquid cooling on your bike?? :silly:

 

[Holt]

guzzibob wrote:

Holt wrote:
The small-block spacer is easy to install, and will allow just about 1 US pint extra to the sump; .

Uhh, no. Added capacity is 1-1.25 QUARTS, not a measley 1 pint, per the guzzitech sale point. Just look at the pix, way more than 1 pint worth of space added. Since stock capacity is a lousy 1.75 qts, this is a substantial increase, & really solves/prevents the potential problem it was designed for.

Well well.
Lets use a metric and understandable measure:

The sumpspacer will increase the amount of oil in the sump to just about 2,7 litres .