a good break in from a engine builder

4cfed

Member
Jan 5, 2009
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fond du lac wi
www.airfoolers.com
get this off janssen motor sports site

Break In Procedures
1) Start your engine and let idle occasionally blipping the throttle for four to five minutes. Allow the engine to cool completely. Repeat this "heat cycle" process four more times.
2) Warm up the engine again and ride the bike for five to seven minutes at a very easy pace, vary the rpm, don’t ride at one speed. Don’t ride at more than 1/3 throttle or more than 1/3 rpm. Let the engine cool down completely and repeat the initial break in ride. Let the engine cool down.
3) Check the base nuts and head nuts for proper torque, check the coolant level and add coolant as necessary.
4) Ride the bike for five to ten minutes at a moderate pace, vary the rpm, don’t ride at more than 3/4 throttle or more than 3/4 rpm. Let the engine cool completely and repeat this secondary break in twice more.
5) Replace the spark plug with a new one. Ride the bike for five to eight minutes at a moderate pace, vary the rpm and shift up and down the gears. Once the engine is up to operating temperature you can make a jetting pass. Start in second gear and ride at full throttle through fourth gear, fully revving out fourth gear. With the throttle wide open in fourth hold the kill button down, pull in the clutch and stop. This is called a "plug chop"
6) Read the spark plug. With a pocket flashlight and a magnifying glass look at the porcelain part of the plug only, as you view the plug from the center electrode look down the length of the porcelain to its base, at this point there should be a dark chocolate colored smoke ring. There was not sufficient time to thoroughly color the whole plug, so the nose of the insulator may still be white, as long as there is a visible dark ring at the base everything is OK. Remember we want break in jetting so the plug should read rich/dark. Richen the jetting as necessary. If your having a hard time reading the spark plug, after the jet pass put the plug in a vice and hacksaw around the plug at the washer. Break the threads off with vise-grips, and the porcelain will be easy to read.
7) Complete the break in by riding at an aggressive pace for fifteen minutes, vary the rpm and don’t cruise at part throttle, ride hard without revving the engine too high. At the end of this final break in session do another jetting pass/plug chop as described above. Check the spark plug for the correct dark/rich condition. Wiseco Piston equipped engines will require another one or two break in cycles, ride at a recreational pace not revving the engine hard, full throttle should only be used for very short periods, fifth and sixth gear should only be used to cruise, ride one tank of gas through the engine in this manner to complete the break in. We feel it take about two gallons of gas to break in a motor equipped with a cast piston and five gallons for a motor equipped with a Wiseco.
8) Replace the spark plug with a new one, ride the bike aggressively for eight minutes and do a jetting pass/ plug chop in fifth gear. If the porcelain color is still dark/rich, lean the main jet size one at a time until the smoke ring at the base of the porcelain is a light brown. If the porcelain base is white, don’t run the engine and contact your engine builder. If the plug color looks good, continue riding at a race pace for ten minutes. Stop and let the engine cool. Check the torque on the cylinder base and head nuts.
9) More on jetting. If you generally run your engine flat out in sixth gear then make your jet pass/ plug shop in sixth. Motocross jetting is checked in fifth gear, therefore it is not safe to run MX jetting in the desert or down a road wide open in top gear. Desert jetting is richer than MX jetting. When running an engine at full throttle for extended periods be sure to chop the throttle decisively to slow down, just rolling out a little can seize a well jetted engine.

Now GO HAVE FUN !!!!!!!!
 
heres one from trinity racing

http://www.trinityracing.com/files/Engine-Break-In.pdf

1. The break-in is very simple. All that you have to do is start the motor and let it idle SLOWLY AND DO NOT REV THE
MOTOR AT THIS TIME (you're not riding it yet). Do this until the cylinders become hot to the touch (about 3 minutes).
2. Turn off the motor and let it completely cool. After this, you must re-torque the base and head bolts (REPEAT STEPS
1 & 2 THREE TIMES BEFORE MOVING TO STEP 3).
SPECIAL NOTE: If you have a head stay on your bike you must loosen this before you re-torque your head (a head stay
is a mount that goes from the frame to the head).
3. AFTER THE THIRD RE-TORQUE, you can start the bike again and this time you can ride it. PLEASE TRY NOT TO LUG
OR REV THE MOTOR. Ride it nice and easy for about one hour.
4. After an hour of riding time, you should let the motor completely cool again and then re-torque the head gasket
only. At this time check the water level (you want to keep it about 1/2 inch over the core). DO NOT FILL IT TOTHE TOP.
5. Now go riding and try not to rev the bike past 9000 RPM and don't lug the motor. Ride like this for about ten hours.
6. Congratulations! You can now ride the bike normally but please use common sense and drive carefully. Be sure to
always wear a helmet.
7. Be sure toWATCH YOUR JETTING and remember that larger motors need more air to run properly and may require
some airbox modifications to run at its potential. And remember to make sure you don't over-oil the air filter!
8. If you have any questions, feel free to call Trinity Racing at 714.632.3434.
 
Wow. I've been doing this wrong for over 30 years! Start the bike, let it come up to temp and shut it off. Do this three times then go beat the crap out of it. I have a bunch of motocross guys that run the Southwick Nationals. We show up with new motors broke in like this and have never had a problem. We also tear these engines down 6 – 7 times a year to change parts. In any event......it can't hurt.
 
everytime i hear break in instructions they differ, i hear from guys who do a few heat cycles then rip on it similiar to Oconnor, then some who spend 25 hours putting it round, doing plug chops, re-torquing, 1/4 throttle, 1/2 throttle blah blah blah, and guess what..... the one that lasts the longest is the one that is maintained the best, ive never seen/heard of a trend in engine failure due to different running in procedures. IMO do what your engine builder recommends, its them thats built the engine and has there research invested in it, if you dont have an engine builder just use common sense, obviously there needs to be heat cycles to actually "mate" the rings to the cylinder wall, Etc but besides the underlying principles and intial break ins, most run in procedures hardly differ in terms of the end results. Just my 0.2 I:I
 
the reason moto cross bikes are heat cycled than ran and raced right away is time.. if your racing every wekend you dont have time to do long break ins.. and with how offent top ends are done on them there not really worried about gettin 5-10 years out of a top end. id follow the long break in for a trail machine, if i was racing.. heat cycle than run it..
i know guys here that do the heat cycles than run it but not hard tell a half tank or a tank of fuel run threw it.

2 strokes running afatter pre mix for break in, 4 stroke change the oil right after break in..

this info i posted was on janssens site he has been building and racing for over 17 years.. they do it all.. 2 stroke, 4 stroke, quads bikes, trikes, sleds, pwc's and usedto do dirt track cars