brethren
New member
I just rebuilt the top end on my Viper after center cylinder overheated. Does anyone have tips for how to break in the rebuild? I was thinking of running one tank of 50:1 premix.
New pistons and rings SPX T-moly series
Replated center cylinder
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New pistons and rings SPX T-moly series
Replated center cylinder
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YAMMIEGOD3:16
Active member
run afew heat cycles threw it first. than retorque your head. you did not post what oil you use, but for break in sure you can add some pre/mix but use non - synthetic oil. 3:16x (yammie tony)
brethren
New member
Oops, that what I have in there now. I'll siphon it out and get some non synthetic (probably yamalube). Thanks for the reply, I'm all ears if there is an oil out there that's better for breakin.
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Sent from my SGH-I337M using Tapatalk
YAMMI X2
Non synthetic oil helps the rings seat with the heat cycles.
Non synthetic oil helps the rings seat with the heat cycles.
YAMMIEGOD3:16
Active member
your fine on break in. 3:16x (yammie tony)
Batwolf
Member
I wouldn't I think you need to do a pre-mix. I saw another post on here a few days ago where somebody asked a similar question and a knowledgeable member had simply advised that starting it while holding the oil pump cable W/O at idle for a minute of so would be sufficient.
Mac
Member
Three choices.
Mineral oil.
Full Synthetic.
Semi synthetic.
Basically all oils are manufactured from a base oil component. The purity of this base determines the ultimate quality. All oils have additives added to the base which determines its intended use. High rpm. Low rpm. Air cooled. Liquid cooled. Semi-synthetic oil is a marketing term and is basically a blend of both and a waste of money. Either buy a plain mineral oil or synthetic. My opinion is that its a complete waste of time and effort to change to mineral oil then back again after break in.
We are not talking about '70/80s steel liners and cast pistons. I believe its old school thought to use mineral oil. Were talking forged pistons nikasil cylinders.
The reason we break in after a rebuild is because the engine gets really hot quickly because you have new rings that are wearing to obtain a seal. This is the first few minutes of run time (break in). This translates into lots of heat and makes the piston expand quickly and if revved up or rode hard during this period can lead to seizure. So take it easy the first ten minutes or so...... then let it rip.
---mac---
Mineral oil.
Full Synthetic.
Semi synthetic.
Basically all oils are manufactured from a base oil component. The purity of this base determines the ultimate quality. All oils have additives added to the base which determines its intended use. High rpm. Low rpm. Air cooled. Liquid cooled. Semi-synthetic oil is a marketing term and is basically a blend of both and a waste of money. Either buy a plain mineral oil or synthetic. My opinion is that its a complete waste of time and effort to change to mineral oil then back again after break in.
We are not talking about '70/80s steel liners and cast pistons. I believe its old school thought to use mineral oil. Were talking forged pistons nikasil cylinders.
The reason we break in after a rebuild is because the engine gets really hot quickly because you have new rings that are wearing to obtain a seal. This is the first few minutes of run time (break in). This translates into lots of heat and makes the piston expand quickly and if revved up or rode hard during this period can lead to seizure. So take it easy the first ten minutes or so...... then let it rip.
---mac---
A couple of bucks
VIP Member
https://www.lasleeve.com/downloads/2-stroke-break-in-procedures.pdf
1. Start your engine and let it 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, and do not ride at one speed. Do not ride at more that 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 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, and do not ride at more than 3⁄4 throttle
or more than 3⁄4 rpm. Then 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 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 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 on the length of the porcelain to its base. 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 you are having a hard time reading the spark plug, follow the proceeding steps: 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 do not 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. If your engine is equipped with a Wiseco piston, continue with the following steps: Ride at a recreational pace not revving the engine hard. Full throttle should only be used for very short periods. Fifth and sixth gears should only be used to cruise. Ride one tank of gas through the engine in this manner to complete the break-in.
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, do not run the engine and contact L.A. SLEEVE. 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 chop in sixth. Motocross jetting is checked in fifth gear, therefore it is not safe to run MX jetting in the desert wide open in sixth. 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.
Remember, the best top-end overhaul, done by the most qualified mechanic, is only as good as your break-in procedure. Good luck!
2-STROKE BREAK-IN PROCEDURES
1. Start your engine and let it 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, and do not ride at one speed. Do not ride at more that 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 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, and do not ride at more than 3⁄4 throttle
or more than 3⁄4 rpm. Then 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 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 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 on the length of the porcelain to its base. 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 you are having a hard time reading the spark plug, follow the proceeding steps: 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 do not 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. If your engine is equipped with a Wiseco piston, continue with the following steps: Ride at a recreational pace not revving the engine hard. Full throttle should only be used for very short periods. Fifth and sixth gears should only be used to cruise. Ride one tank of gas through the engine in this manner to complete the break-in.
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, do not run the engine and contact L.A. SLEEVE. 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 chop in sixth. Motocross jetting is checked in fifth gear, therefore it is not safe to run MX jetting in the desert wide open in sixth. 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.
Remember, the best top-end overhaul, done by the most qualified mechanic, is only as good as your break-in procedure. Good luck!
2-STROKE BREAK-IN PROCEDURES
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I do it easy way and its never let me down yet. just start up the sled, hold the oilpump cable open for a minute or two, and let the sled get good and hot, shut it off and check everything for leaks.
If good, just go out after its completely cooled off again and start it up, ride it as you would normally.
you don't need to add premix to the tank, youll only lean out the air to fuel ratio doing so, more oil means less gas, which in turn means lean air/fuel ratio because the oil took place of the gas. That's old school stuff , not needed with todays moly coated rings and plated cylinders. You can even still use your synthetic lube in the tank, it will just take a tad bit longer to fully seat but the rings will be broke in and seated in the first 50 miles anyways.........go ride!!!
If good, just go out after its completely cooled off again and start it up, ride it as you would normally.
you don't need to add premix to the tank, youll only lean out the air to fuel ratio doing so, more oil means less gas, which in turn means lean air/fuel ratio because the oil took place of the gas. That's old school stuff , not needed with todays moly coated rings and plated cylinders. You can even still use your synthetic lube in the tank, it will just take a tad bit longer to fully seat but the rings will be broke in and seated in the first 50 miles anyways.........go ride!!!
brethren
New member
Thanks for all the tips, I I've already taken the synthetic oil out, so might as well run the first jug of mineral base through it. I like the idea of pulling the cable for the first few minutes, and several heat cycles. I also think it's important to vary the throttle for the first couple of tanks. I never thought adding more oil would lean out the fuel air ratio but it makes scene, so I will not be adding oil, but may adjust the cable for a bit more oil (can't help myself). Thanks again to all.
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Sent from my SGH-I337M using Tapatalk
With respect to the OP and his question, can you fella's weigh in on how to properly break in a steel lined cylinder? Would it be prudent to switch to mineral oil for break in? Any specific steps to follow?
Anyone...?
I like this method the best, and would ad that if you want to get the most out of the engine(HP wise), after the heat cycle, ride it like you stole it...this goes for just about any engine. Got to seat the rings, you only get one chance at this.