Please don't hate me. Not asking which brand or comparing statistics. Just wondering if there are any negatives to changing to full synthetic.
I've used Motul 3000 Dino oil for the first 9,000 miles. I'd like to try Mobil 1 MX4T synthetic. A good percentage of you use Mobil 1 so that's good enough for me. I'll keep using the Purolator Pure One PL14610 filter.
I don't think there's any doubt that a full synthetic has advantages. My main questions/concerns are:
Is there any problem with waiting 9,000 miles before switching?
Is there any REAL/common problem with gaskets tending to leak when changing to synthetic? I'm most concerned about the valve cover gasket that I've heard often leaks. I've had NO leaking at all, anywhere.
Does approx' 4,000 mile oil changes seem right with the synthetic?
If I decide to go back to Dino oil, are there any issues?

I found Mobil 1 for $10/qt at Autozone which is fine with me. About $3 more per qt than the Motul Dino but from what I'm reading I should at least TRY a full synthetic. Extended oil changes make up the cost anyway, not to mention better protection. Just want to be sure about my decision. I appreciate the help.

Is there any problem with waiting 9,000 miles before switching?

Do you mean 9,000 miles on one change of petroleum-based, or total miles?

Is there any REAL/common problem with gaskets tending to leak when changing to synthetic? I'm most concerned about the valve cover gasket that I've heard often leaks. I've had NO leaking at all, anywhere.

Not on my cars, not on my bikes, ever.

Does approx' 4,000 mile oil changes seem right with the synthetic?

I do a whole riding season on 1 change of Amsoil, and it comes out still looking good. Amsoil says I can do 15,000 miles and still have enough viscosity to lubricate well. And synthetic does not break down into acids like petroleum-based oil. So put it this way, change it once a year, at the end of your riding season, and you'll be fine.

If I decide to go back to Dino oil, are there any issues?

Same as going from dino to synthetic. Completely drain the pan and replace the filter. Fill with new oil. Of note, Amsoil says it won't hurt if a little mixing occurs, but obviously the point of going to synthetic is, among other things, not having anything that will turn to acid in the oil.

Peas and Q's don't hate me, but I run half syn and half 30 year old oil without the SAE pedigree for a modern engine. No leaks out of the gaskets and one is brand new like the valve cover gasket(s) and she is as dry as the day it was new. So say it's some squid re-using a used gasket over again; the assumed fallacy beings. Shouldn't my bike be leaking/weeping/help, I need a washer over my valve cover but don't hate me, mine still does not leak a weep.

* Last updated by: Hub on 8/1/2011 @ 4:06 PM *

privateer, I meant is there any problem with changing from dino oil to full synthetic after the first 9,000 miles running only dino oil. Seems most members here wait about 2 or 3,000 miles before changing to synthetic but I assume those numbers are related to making sure the engine is fully broken in with dino oil? So waiting until 9K shouldn't matter but thought I'd ask.
I've just read awhile back that if you have a bike with quite a few miles and change from dino to synthetic you can get leaks. Something about the crud in the motor helping to seal but the synthetic cleans that away and then the gasket leaks. Also, when we bought our Chrysler 300 new the dealer said if we go with synthetic after break in, don't go back to dino after that. I don't know why.

Hub, I had to start the thread off with the please don't hate me stuff 'cuz of how you can get blown out of the water here just mentioning the "O" word.
What do you mean you have to use a "washer over your valve cover"? Dun u hate me but pleez 'splain to me.

* Last updated by: KAK on 8/2/2011 @ 12:30 PM *

KAK, where is this hate'inn coming from? I'm mixing and matching oils and now I hear someone tell you not to revert back to the cheap stuff? Am I not goofing on what is told to you not me coming after you in a personal way. Same as chasing the ones down the road that band-aid fix a failed gasket that has a leak at the top cover. It says you need to replace the gasket, not crush the crush out of the cam tower threads.

So say the band-aid fix turns into a nightmare of a heli-coil session where it was the gasket failure with a simple fix like check your valves once and awhile and change out the heat soaked, beginning to shrivel, won't line up like new if reused; already has a flat spot, no more spring to push itself closed. More it sags at that area of burn/heat/hydraulic move on the assembly; like keep the surfaces dry on assembly. That way there is no way for the oil to travel, you thought you squeezed the oil out by closing the cover? Nope/usually there begins your weep out the coversandshit.

You are past any break-in. What I found out is that full syn will slip the clutch until it wears out in a few hundred to a 1000 miles or so. Then the clutch bites back again, no slip.

I tried Repsol 4T synthetic racing oil at 3000 miles, i think it was---sure not all the way to 9000 miles.

To tell you the truth i THINK that is when I started noticing oil loss. I was not extremely impressed with the oil and I changed after 2500 miles. The slick running was not long lived. stuck with conventional oil all the way to 28,500 miles. Just put this in and I like it fine. If it doesn't last it is cheap enough to change after 2500 miles.

I will be changing the head gasket soon so it will be baptised in synthetic. If it leaks in 3000 miles i guess i will be convinced that conventional is the only oil to use.

I'm sure you will be fine switching to synthetic as far as engine break in. No idea about conventional causing leaks.

Thanks for the replies.
I checked out the Mobil 1 site. Shouldn't be any concerns about switching to synthetic or going back. Now if you had a high mileage bike/vehicle that always ran dino oil then changed to a synthetic, they say if you planned to change the synthetic every 5,000 miles you should shorten the first oil change interval to 2,500 miles, then the next change at 3,500 miles, then stick with the 5,000 routine from there on. The thinking is the synthetic will wash away crud left behind by the dino oil and contaminate the new synthetic so you want to change it earlier and get the motor flushed sooner. But I can see where older bikes could show leaks after changing. Makes sense. Interesting that there seems to be no standard amount of miles between changes with synthetic. Highest mileage interval mention was 10,000 and dropping to as little as 3,000. 5,000 seemed an "average" for motorcycles using 4T synthetic.
Pretty much any question you have is answered at their site.
I bought some Mobil 1 4T today so I plan to change it this weekend and I'll see how it works compared to the Motul 3000 dino. I want to see how it performs before changing my clutch springs to the Brock's HD springs so any changes I notice are related to the different oil. One thing I noticed that bugged me was the date on the bottles. All were dated 2/26/11. Over 5 months old. I didn't think to look until I got home. Mobil uses a type that you can barely see on the bottle. For my cars I've always bought Pennzoil dino and the oldest I ever bought was about 3 months. I checked the Mobil site about this and their answer is the synthetic has an approx' 5 year shelf life so 5 months is nothing I guess.

Hub, anyone, I haven't heard about clutches slipping from synthetic, even if only temporary. Mobil 1 is supposed to have additives to stop that from happening(?)

* Last updated by: KAK on 8/2/2011 @ 11:00 PM *