HOW TO Break in new motor????

[vancejohnson88]

hey all i rebuilt my motor. and i mean everything is new except the case. its an 01 800 mountain cat not that is matters but what is the proper break in method? what my plans are to put some extra oil in my gas tank for the first 1-200 miles and just dont keep it pinned until i get 100 or so miles on it?? Should I run it for 20 minutes and let it cool?? i dont really know the right way. let me know what you all have done and think

 

[NoSecondChances]

IMO - lots of varying throttle speeds, don't just run along at 50 mph for 2 hrs. Keep the RPM's going up and down, no hard pulls for the first little bit, don't put any big loads on the motor (no doubling etc) and don't let it get too hot. Run it a few miles, then stop and make sure everything is ok, check bolts to make sure they are all tight, clutch is not about to fall off, etc. Oil in the tank is a good idea, just make sure you use the same as you will be runnning in your injection or drain all the gas from your tank if you are going to run sythetic in your injection, don't mix oils, never use a synthetic oil to break in a motor.

 

[007]

IMO - never use a synthetic oil to break in a motor.

whatever!

KJP

 

[gcmci]

Originally Posted by NoSecondChances
IMO - never use a synthetic oil to break in a motor
Why not?
I have broke in lots of motors with syn oil,it doen't hurt anything or cause any problems.
Greg

 

[Leterip]

Yah, i guess you shouldn't use syn, so just go suck all the oil outa the tank when you buy a new one, since that's what most of them come new with. but i do agree non syn oil is better for break in, it just takes longer for the rings to seat with syn. and i don't fully agree with not loading your motor hard, it has to be done with caution (no really long up hill pulls), how else can the rings/cylinder get cut with low cylinder pressure, it's going to happen sooner or later

 

[OntRider]

On my new sleds, I've typically just ridden it normally (which is varying the speeds because of the trails here in the east) and no WOT runs for the first few tanks. Never had a reliability problem.

Oh, and they've all been broken with with syn oil (Amsoil or BRP) from the 1st mile...

Since you're doing a rebuild, I definitely agree that it's worthwhile stopping once in a while and checking for loose parts.

 

[sleded700]

ride it like you always would, add a bit of oil to your gas tank, and have fun. 2 stroke engines are made for revs, your rings will seet in about 200 miles, just avoid the same constant speeds for long durations( but you should always avoid this anyways new or old). I have broken in 7 new sleds over the past 12 years, and 2 renbuilt engines, never once had a problem

 

[vancejohnson88]

yea i already have synthetic apv oil in the motor so im not going to swap that, but hopefully i can get the motor broke in, in 3 or 4 rides. I know letting the motor warm up is just good practice so it doesnt seize up on you. at least this was on my 2 stroke dirtbikes.. does that happen on sleds as well? (cold seizure) but thanks Vance

 

[summitdude]

I warm up the engine fully...then with hard full throttle pulls (5-10secs)....de-accelerate..then again accelerate hard! my last 2 sleds(4 seasons of riding) i broke-in this way! never had engine problems..and my sleds ran strong! i dont use synth for break-in!

i read this article online..and now its the way i do it!

http://www.mototuneusa.com/break_in_secrets.htm




.

 

[OntRider]

Yup, cold seize can be an issue... I let my sled warm up completely while I get dressed.

 

[NoSecondChances]

whatever!

KJP

LOL, I wondered how many responses that was going to bring out when I put it down. don't get so worked up guys. Using regular oil won't hurt the break in procedure either IMO.

This used to be a standard used by most professional engine builders, call up your local trusted performance sled shop and ask them what they would do, don't believe everything you read on the internet. Breaking in a motor and seating rings is a standard procedure and basics should be followed regardless of the motor type and what it is built for IMO. Never in my entire life, have I (or seen any engine builder) hooked up a motor to a dyno and run it full out without any break in procedure. Last time I checked Leterip, most of the new sleds did not come with synthetic from the factory (I don't see Ski Doo filling new sleds with the XP-S fully syn, just the good ol' mineral oil), maybe you can verify if they are, I don't own a new sled. Yeah you can run synthetic if you want, probably won't hurt anything, IMO. If its already in the tank, go for it. The Dodge Viper comes from the factory with synthetic in the motor if that helps your resolve any. Here are some others -

Aston Martin
Bentley Amage and Bentley GT
BMW all models
Cadillac CTS, XLR, SRX and STS
Chevrolet Corvette
Mercedes-Benz AMG vehicles
Mercedes SLR
Mitsubishi EVO
Pontiac GTO
All Porsche vehicles
HD Screamin eagle bikes

With the modern engine technology and material types, you can pretty much use any oil you want IMO.

Also I did not say "don't 'load' the motor", I said "no big loads" on the motor (no pulling a 500lb toboggan while doubling your wife and then kid strapped between your legs with an extra 5 gallons of fuel on the back rack) IMO.

 

[Gimpster]

A fresh motor, new pistons, rings, cylinders etc.., need time to finish the machining process.
New ball bearings also need some break in time.
Even though the engine was machined to perfection, all components need to 'get used to each other'
All engines I build when first run get pretty much the same break in time. I will initially fire them up and keep the idle a few hundered rpms above normal until the cylinder is warm to the touch. Cool down time is next. I will let them totally cool without any fans blowing on them to accelerate the cool down time. Once the engine is cool to the touch. I will fire it up until warm to the touch again, then cool down. Repeating this proceedure 5 or 6 times will let the pistons and rings, bearings machine themselves needed for smooth operetion, minimal issues, and bettter overall performance of the engine after long term use.
Do add extra oil, on a 2 stroke, to the first tank of fuel and when the engine is initially started, hold the oil pump wide open to release trapped air from the oil lines and give the tight engine some extra lube. Note the air in the oil lines when the engine begins to smoke heavy. No air present, release the oil pump to normal operating position.
Revving the engine cold or running it like you stole it, from the first initial start-up can be asking for trouble from scored piston skirts, chattered rings harming ring lands and cylinders may result. I have also seen crank bearings chatter which will lower engine performance and cause drivability issues at higher rpms.
I prefer mineral oil for initial break in, but following the above outlined initial start-up proceedure, synthetic oil use should be fine
Enjoy the fresh engine overhaul

----- Gimpster -----