Semi-Synthetic oil: Safe for break-in?..

Pablo said:
Cam lobes don't wipe because an oil is "too slippery". That's tall tale material. Cam lobes most often - probably in 90% of "cam failures" - fail due to poor cam metallurgy, not the base oil of any given lubricant. (And the remainder due to inadequate oil supply to the cam)
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I can verify that "cam metalurgy" comment. My '71 Vovlo suddenly started sounding like a jack hammer due to a couple worn cams. Drove around for almost a year with tappets/rods removed from 2 cyclinders. Excellent mileage but had to drive around hills instead of up them. Found out Volvo had a recall due to hard tappets and hard cams. Hard on hard no good. One should be softer metal.
 
Synthetic oil is great for break in from day one on the engine. I used to
build motorcycle engines and drag bike engines, and we reluctantly tried the Mobil 1 synthetic oil in fresh new rebuilds. After a few tear downs of our engines during summer drag racing, the engines broke in fine and all the parts had a beautiful golden color without galling or piston rings damaged. The bearing and cam lobes looked great too. We were very impressed. I'm talking about 150 to 175 engine rebuilds
from street to drag racing and Synthetic oil is the way to go!. Did
you ever notice that the high end cars, like BMW, use full synthetic
oil in all their engines brand new?
 
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well this thread is contradicting everything Ive ever heard about synth and break-in - i do trust Pablo's opinion also - Thank god I was wrong LOL - i guess - still interested in how you motor will hold up over time noob
 
my first bike i didnt think about it and used lucas semi senthetic for break in. then i heard it wouldnt break in so the second gallon i used regular 2 stroke oil. the third went back to semi senthetic.
the second third and fourth broke in on regular 2 stroke oil. the first motor is the fastest!! 37mph top speed on stock 44 tooth I think you are good to go !! run that mother!!
 
As i stated earlier my motor has only ever run on lucas semi synth and has dynoed with more power than the factory states
If you think its wrong thats a personal opinion, but its wrong! Telling someone that there motor wont work as good as one broken in on normal oil is just crap!
Reving a new motor with no load, well your just asking for trouble.
 
Thank You all for the comments, I think for my 3rd gallon tomorrow I shall be sticking with the Lucas semi-synth @ 16:1. My stock plug looked quite fouled... and this new Champion L78c actually runs slower and has less hill climbing power than the stock plug... will try to get a pic of my stock plug on tomorrow.

p.s... no amount of oil could ever cure what's wrong with a 350 Chevy crank imo.. (sorry had to add it...)
 
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noobtard said:
Thank You all for the comments, I think for my 3rd gallon tomorrow I shall be sticking with the Lucas semi-synth @ 16:1. My stock plug looked quite fouled... and this new Champion L78c actually runs slower and has less hill climbing power than the stock plug... will try to get a pic of my stock plug on tomorrow.

p.s... no amount of oil could ever cure what's wrong with a 350 Chevy crank imo.. (sorry had to add it...)
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Noobtard you should be fine to go to 25 to 32.1 and you wont foul the plug

Ps pushrods suck! (sorry had to add that)
 
Cabinfever1977 said:
let me know when you see bmw 2-stroke bike engine kits for sale.
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it amazes me that Outrunner has stated that he has real world experience in building motors 150 - 175 wow,
yet you still dissagree. What proof have you got to support your claim? If you think that ya use cheap oil because these motors are cheap, keep useing the crap stuff
Because theres no point saying that you cannot use it if ya cannot back it up. ask a gokart racer what oil they use
 
Cabinfever1977 said:
Pablo says that sythetic oil is ok for breakin so you should be fine,but its your choice.
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Pablo said:
There are a LOT of engines that come from the factory filled with synthetic oil now days. Guess what? They break in just fine. I've been messing with and rebuilding engines for almost 40 years. A lot of them with synthetic. Broke in just fine. No glazed cylinders.

Use the oil that makes you happy!!
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I've seen for myself how well synthetic oil works. I have been told time and time again to avoid synthetic during break-in due to its superior lubricating ability. So far that advice has proven to work just fine so I will continue to do that. As soon as the rings are broken in however I like to pour something with moly (Duralube etc.) into the crankcase and swish it around as best I can for the bottom end. I also switch to synthetic at this time.

I seem to have fewer engine problems than alot of other people and that makes me happy :)
 
For what it is worth, I broke mine in with regular oil for the first 300 miles. Then I changed to synthetic. The switch had noticeable results. Now I can rev over 8000rpm and I have very little vibration in my engine, it vibrates about as much as riding a regular motorcycle.
Maybe it is because I broke in with regular 2-stroke oil, maybe it is because how I mounted my engine, maybe I just got lucky in the HT engine lottery. I dunno, but whatever I did seemed to work. Thing pulls right along, up hills and everything just fine.
 
Okay, I'm now Officially a "Semi-Synthetic/Synthetic = BADDD for break-in" Club member.

I switched to 32:1 for my 3rd gallon (because I listened to people -- think I may stop doing that so much..)

At first it ran Awesome. I gained Alot of speed and power.(probably because the rings still actually had a little bit of oil in them...)

Today, ran like total crap.

At first I suspected the plugs, they were both semi-fouled.. cleaned them with contact cleaner + wire brush.. changed nothing...

Today WOT was like my Half throttle used to be... lost tons of speed and power.

I dumped a bit more oil in my tank, gained a bit of my original 16:1 power/speed back..(which = my rings haven't even set yet in my book) though, it doesn't want to idle too great anymore.

Sooo, I will be using what's left of this gallon with more semi-synth added.. And then, I'll be switching back to 16:1 with regular 2-stroke oil.. and just pretend it's a new motor... and hopefully get away with it...

I do care somewhat about my motor, I R broke.

Results may vary I guess. . .
 
I hope the motor isn't permanently coated with the stuff. Similar to what Slick 50 does. If it doesn't come back after run a few gallons of reg stuff. You may have to rebuild and clean the parts. But wait for other opinions. I really really hope I'm wrong and it just sorta flushes out.


Then again it could be something else entirely
 
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Well, after 6 gallons of gas(3 semi-synthetic and then 3 regular 2stroke), my motor is finally broken in.

decided to chance it and go back to semi-synthetic 32:1 on the 7th gallon.. seems to be running fine.. except, I've been noticing some "pinging"...

any ideas there?..
 
Cannot say why your pinging, but a few ways it will ping. more ways im sure
To much Compression, to much ignition timing, to lean, to hot

If you deck the head or block or get the motor hot the piston can expand giving less piston to bore clearance also incresing compression.

Timing is hard as there all keyed, Are they all keyed the same. I dought it

More oil lowers the octain rating and leans the fuel mix out ie less petrol per drop.
each of these alone could make you ping! combined... phow
 
If the top of the piston is carboned up enough you can get a "glowie" on the top that can pre-detonate the mix. If this was the problem you could tell by the motor not pinging till it was fully warmed up. I never heard of it happening in a 2-stroke motor but that doesn't mean it can't. It's the same thing that will make a car keep running after you shut the key off. I'd see if it still happens when you goto 32:1 synthetic oil mix.
 
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