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After a tough mountain climb I can hear my oil boil. Has this ever happened to any of you guys. My bike still runs great so if it is to lean would that be the main or secondary jet??

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<font color="navy">You can HEAR your oil boil? What the heck does that sound like? How do you know it's your oil? If you're concerned about your engine temp, I'd purchase an oil temperature dipstick like the ones XR's only makes >> clicky << for some peace of mind. Anyway, to answer your question, I've never felt I could hear my oil boil. Curious what sound you're hearing to make you think that!

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Its probably not the oil. I have seen gas boil due to the heat of hillclimbing though.... the results werent fun but no fires!

Both riders had one-way tank vent capsules in their tank vent lines, and the pressure couldnt escape. One way vents actually are supposed to allow gases to vent both ways, but block liquid flow out of the vent. Their vents must have been gummed up.

Both bikes began running very rich, and fuel was pouring out of the carb overflow. We pulled the tank caps off, and saw it with our own eyes!!! Pulled the one-way vents, end of problem.

The XR has the one-way valve made into the cap. You may be able to clean it with carb cleaner.

Check out www.designengineering.com, they sell self adhesive heat shield, line the underside of your tank. Cool fuel makes more power. Check the 1 inch header wrap, that will keep the header heat from radiating back into your engine, making it run much cooler.

Robert :cry:

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I heard a sound last weekend (first time I noticed it) that could be likened to a boiling sound. I think it is oil bubbling/draining out of the oil cooler back to the frame and or sump.

Joe

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If it is a sound you hear when you've stopped and everything is quiet, it might just be the gas tank vent tube. A bit of gas ends up in the baffles inside the gas cap, and as you stop and all is quiet you will hear the gas vapours gurgle through the bit of gas in the gas cap baffles. Pull the hose from the steering stem and listen if in doubt.

If you are indeed boiling the oil, then that is definitely not a good thing. Conventional oils start to lose their lubricating properties when overheated (>300F). Your top end will grind itself to death in short order. :cry:

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I've thought about the header wrap before since the pipes pass so close to the frame down tube / oil res., but I was concerned about how hot the pipes (and head flanges might get. With no way to radiate heat, it looks like the pipes would get hot enough to carbonize and heat treat to the point of embrittlement. Does anyone here have any longterm experience with wrapping the pipes?

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I guess it could be the oil draining out of the radiator on the frame. That is where the noise is coming from and the motor itself did not seem to be excesivly hot.

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I've thought about the header wrap before since the pipes pass so close to the frame down tube / oil res., but I was concerned about how hot the pipes (and head flanges might get. With no way to radiate heat, it looks like the pipes would get hot enough to carbonize and heat treat to the point of embrittlement. Does anyone here have any longterm experience with wrapping the pipes?

Ive had wrap on my XR400, XR100 {FMF pipe},and TRX250 far a little over 3 years now, nothing has happened yet. Even if the header failed right now, I figure I would be ahead.

Robert :cry:

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After a tough mountain climb I can hear my oil boil. Has this ever happened to any of you guys. My bike still runs great so if it is to lean would that be the main or secondary jet??

If running conventional oil and high RPM , YES, I too have heard oil boiling in the head on someone elses XR running Castol GTX. I could smell it also as I gained on this XR . Once I passed him the smell went away. I had thought it my bike. Later I smelled the burning oil again and followed my nose up wind and found this XR and it was gurgling from the engine. NO GOOD. I run the best Synthetic MOTORCYCLE JASO MA rated oil I could get. I never had any problems and found my engine ran cooler also. It seemed to help clutch life too. ( Maxima Extra 100% synthetic , 15W50 )

Oh, yes, this guy called me a couple weeks later looking for a good used head , cam and cam followers.................... Good used head, YEAH RIGHT !

Cher'o,

Dwight

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<font color="navy">I still find that hard to believe. The boiling point of motor oil is very high (well over 500 degrees)... A motor would fail long before it got to that temperature.

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Yup, and the boiling point of gasoline is lower than water. Sorry, I dont have the exact temperature. But with gas at just room temperature, the fumes you smell would equate to water in a pot being heated, I would estimate 140 deg. The gas will boil at a lower temperature as the altitude rises.

Like I said, next time you hear it, pull the cap and have a look. My bet is still fuel boiling, not oil.

Robert :cry:

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Doubters , eh ?

I guess you have had more experiance than me.

Cher'o,

Dwight

PS: the boiling point of conventional oil is much lower than 500 degrees.

16 years racing XRs

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Not doubting, just stating my opinion that the first fluid carried by an air cooled motorcycle to boil will be the fuel, and that I have personally witnessed it on 2 bikes on the same day, during hard uphill riding, at the same time,

through visual inspection of the fuel through the filler opening.

I am just as sure than the experience you gave is just as valid.

Robert :cry:

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PS: the boiling point of conventional oil is much lower than 500 degrees.

<font color="navy">Where do you have stats (seriously, I'm curious -- hard to find). Here's a MSDS (Material Safety Data Sheet) on oil rated at 5W-30, 15W-50, 10W-40, 20W-50 and it lists boiling point as 599 degrees Fahrenheit...

http://www.noco.com/NOCO-MSDS/Premium_4_Motor_Oils.htm

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Here's the MSDS's on some el-cheapo dino based automotive oils just for reference.

The boiling point listed for Castrol GTX 10W40 is 500F.

http://kauai.hawaii.edu/msds/files/ckh/ckhjy.html

The boiling point listed for Valvoline 5W30 exceeds 500F.

http://msds.ogden.disa.mil/msds/owa/web_msds.display?imsdsnr=143913

The boiling point listed for Chevron Delo 400 is in excess of 600F.

http://www.setonresourcecenter.com/msds/docs/wcd0000c/wcd00caf.htm

The boiling point listed for Kendall 20wt oil is in excess of 626F.

http://msds.ogden.disa.mil/msds/owa/web_msds.display?imsdsnr=133843

The boiling point listed for Conoco feelt heavy duty oil is 650F.

http://msds.ogden.disa.mil/msds/owa/web_msds.display?imsdsnr=185098

The boiling point listed for Penzoil 10W40 oil is in excess of 800F.

http://msds.ogden.disa.mil/msds/owa/web_msds.display?imsdsnr=40592

The boiling point listed for Penzoil 30wt exceeds 900F!

http://www.setonresourcecenter.com/msds/docs/wcd00031/wcd031f0.htm

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The flash point is the point I guess I am speaking of as that is the point that oil vaporizes where it could be possibly ignited. The Castrol GTX Flash Point: =212.8C, 415.F

That would be the point that you would hear gurgling in the head.

The flash point for the Chevron Delo is Flash Point 392 degrees.

Penzoil 30wt. Flash Point is 424

I wasn't speaking of a full boil but to the point that the oil is vaporizing in the head.

Good information though.

Cher'o,

Dwight

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Here's some info about the flash and fire points of Maxima Ultra full synthetic and Maxima Extra synthetic blend motorcycle specific oils for comparison.

Maxima Ultra 5W50 flash point = 400F

Maxima Ultra 5W50 fire point = 450F

Maxima Extra 10W40 flash point = 410F

Maxima Extra 10W40 fire point = 440F

source of flash & fire point info:

http://www.quad-maths-racing.com/productslink4.html

Maxima makes a top notch product and I feel they're truly offer one of the best oils made for our bikes. I don't regularly use their products, but I would never be concerned about running any of their products in any of my bikes. I just wanted to post their numbers for comparison. Maxima is one of only a few companies who uses a very high ester content (found in their Extra & Ultra products) and if anyone is ever looking for a high ester oil, then consider their Extra or Ultra products as they're excellent choices.

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