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Thread: Engine Break In
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post #2 of (permalink) Old 01-16-2006, 09:15 PM Thread Starter
Vulcan Verses
Join Date: Jan 2006
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Q: What is the most common cause of engine problems ??? A: Failure to: Warm the engine up completely before running it hard !!!
Q: What is the second most common cause of engine problems ???
A: An easy break in !!! Because, when the rings don't seal well, the blow-by gasses contaminate the oil with acids and other harmful exhaust by-products !! Ironically, an "easy break in" is not at all what it seems. By trying to "protect" the engine, the exact opposite happens, as leaky rings continue to contaminate your engine oil for the rest of the life of your bike !!

A Picture's Worth A Thousand Words... These Honda F3 pistons show the difference. The one on the right was broken in as per MotoMan's instructions. After a full season of hard racing: Perfect ring seal, no scuffing, lots of trophies !! Both came out of race bikes, and their owners used the same type of fuel and oil. The only difference was the break in method they used... The one on the right was broken in as per MotoMan's instructions. The one on the left was broken in exactly according to the owner's manual. The resulting leaky rings have allowed pressure to "blow by" down into the crankcase on acceleration, and oil to "suck-up" into the combustion chamber on deceleration. Needless to say, this bike was slow !! It's up to you: The loss in power from improper break in and the resulting poor ring seal can be anywhere from 2% - 10% !!

Q: What's the third most common cause of engine problems ???
A: Not changing the oil soon enough after the engine is first run !! Change Your Oil Right Away !! The best thing you can do for your engine is to change your oil and filter after the first 20 miles. Most of the wearing in process happens immediately, creating a lot of metal in the oil. Plus, the amount of leftover machining chips and other crud left behind in the manufacturing process is simply amazing !!

You want to flush that stuff out before it gets recycled and embedded in the transmission gears, and oil pump etc... 3 more words on break- in: NO SYNTHETIC OIL !! Use Valvoline, Halvoline, or similar 10 w 40 Petroleum Car Oil for at least 2 full days of hard racing or 1,500 miles of street riding. After that use your favorite brand of oil.

Q: If break- in happens so quickly, why do you recommend using break- in oil for 1500 miles ??
A: Because while about 80% of the ring sealing takes place in the first hour of running the engine, the last 20% of the process takes a longer time. Street riding isn't a controlled environment, so most of the mileage may not be in "ring loading mode". Synthetic oil is so slippery that it actually "arrests" the break in process. I've had a few customers who switched to synthetic oil too soon, and the rings never sealed properly no matter how hard they rode. Taking a new engine apart to re - ring it is the last thing anyone wants to do, so I recommend a lot of mileage before switching to synthetic. It's really a "better safe than sorry" situation.

Q: What about the transmission gears, don't they break - in ??
A: Yes they do !! The faces of the gears have a slight roughness to them. After a while the roughness goes away and the gears have a more polished look. There must be an additional amount of friction, but I've never seen a new bike run noticeably hotter because of it. So while the gears do "break in" there's no reason for adhering to any special rpm limits out of worries about gear or heat damage.

Q: What about the main and rod bearings, don't they break - in ??
A: Actually, the operation of plain bearings doesn't involve metal to metal contact !! The shiny spots on used bearings are caused from their contact with the crankshaft journals during start up after the engine has been sitting a while, and the excess oil has drained off. This is the main reason for not revving up the engine when it's started. The subject of plain bearings is one of the most mysterious aspects of engines, and will be covered in a future issue of Power News. In it I'll reveal more information that fully explains the non-contact phenomenon.

Q: Why change the oil at 20 miles ?? Doesn't the oil pick up screen catch the aluminum chips ???
A: It's true that the screen stops the big pieces, but the transmission gears and their ball bearings are unprotected by the filtration system !! After the transmission gears chew the loose aluminum bits into paste, they do get past the screen. A close examination of a new engine will reveal lots of aluminum deposits on steel parts. This aluminum coats and tightens up the clearances of the parts, which creates a loss of power. Most of the time I spend "blueprinting" an engine is actually inspecting every part and "de-aluminizing" them !!

Q: What about the oil filter, doesn't it catch the metal paste ??
A: When soft metals are loose in the engine, they get pulverized by the gears and oil pump, and the super fine particles do get past the entire filtration system. These particles are too small to "scratch" the bearings, but they do something much worse ... they coat them, and take up the oil clearance !! Tight oil clearances cause a power loss, and really tight clearances cause seizure. I prefer to remove the oil pan and clean the aluminum bits out of a new engine out that way, but a $20 oil change is an easy and inexpensive way to flush the initial particles that come loose in the first miles.
Q: What about motorcycle v.s. car oils ???
A: This is a topic all by itself !! It will be covered in a future issue of Power News.

Q: Will this break - in method cause my engine to wear out faster ???
A: No, in fact I always opt for reliability before power !! The irony here is that by following these instructions, you'll find that your oil is cleaner, the engine will rev quicker from not being "aluminized", and you'll have better torque and power across the power range. Reliability and Power are 100% connected !! I hope this page will help you to make an informed decision about how to break in your new engine. If you have any more questions, e-mail me !! Sincerely, Pat McGivern ~MotoMan
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