Sorry, but I have an oil question...

I've been running Honda HP4M w/ moly (as per owners manual instructions) since I broke-in my 2002 CRF. I even have an interview with Mr. Yamasaki and Mr. Shimura (Honda engineers) and I quote...

"Why are engine and gearbox oil seperate? Gearbox oil has very different demands from engine oil. The meshing of gears and the contamination of a wet clutch require an oil without complex, easily damaged molecules. Also, substances like moly are excellent lubricants for a cam, piston, and cylinder, butcan cause a clutch to slip. By separating the two chambers of the engine, the CRF can get more life out of it's oil."

My 2005 manual now suggests using HP4 without moly and warns not to use "energy conserving" oils. I'm talking about the engine side not the tranny. :cry:

What gives? Why did Honda switch positions? :cry:

I would really like start running moly in my 2005, because I had great reliability with my 2002. What do you guys think?

As long as you use a quality oil and change your oil often, you shouldn't have any problems. I always change the filter at every oil change myself. I run the Honda HP/4 w/ moly in my 03, and have not had a bit of problem. Why Honda would change their tune, here is my opinion. Honda is trying to get more top end rebuilds out of their customers. They have a large surplus of pistons and valves, and since using good oils that are "slick" and have good bonding properties, their engines are not needing rebuilds as often as they would like for parts sales. Personally, I think the 15 hour top end rebuild is a bit ridiculous. I quit trying to figure up the hours on my 03, but I know it is well over 15, and it shows no sign of needing a rebuild. Hope this helps.


Run the slickest oil you can find in the engine side. Put what ever you want in the trans as long as it doesnt contain friction modifiers that will impact the clutch negatively (cause it to slip).

After I broke my 03 in, I ran 15-50 MobileOne with 20% Slick 50. The trans side has always gotten regular dinosaur oil.

The hour meter on my bike says 40.9 now, and it runs like brand new and burns zero oil. Matter of fact, the last oil change kind of surprised me as the trans oil after 5 hours came out clean, like I could still see through it clean. And it was good and hot when I drained too.

I just run the mobil 1 red cap in my bike and it runs great, before i ever did a top end on it, which was probably about mid summer this year, the bike had probably somewhere between 400-500 hours on it. It still ran like a champ before i changed out the piston. :cry:

Oh by the way, i still havent had to do anything with my valves besides shim them once :cry: :cry:

I believe Honda is simplifying the choice. We recommend 2 to 4 oil changes with petroleum based oils, before going to a semi or full synthetic. The moly (not energy conserving) oils are just too slippery to allow proper break-in. Honda won't say anything about moly on the engine side after break-in, just be smart with it.

We intentionally tried HP4 w/moly on a brand new '04 CRF450R, the rings never seated for the 1st 4 tanks of gas, would puff blue smoke on start-up and when throttle was whacked open. Changed back to petroleum for 3 changes (quick ones, about 3 hours each), and finally got the motor broken in. Very interesting. No harm , no foul, this bike has 800 miles on it, no problems.

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