I got a 62t 701 for my squarenose and it was just rebuilt what should I do to break it in.
701 break in help
- Thread starter doubletrailerz
- Start date
Run 32:1 regular mineral oil. Put it in the water and let it idle for about 10 minutes on the trailer. Then go out and ride it under about 25% throttle for the next 20-30 minutes while varying the throttle...I know it's boring. Then come back and let the engine completely cool for at least 30 minutes. Ride it again for 20-30 minutes but don't go above 50% throttle this time and still continue varying the throttle. Then 75%...
You're not supposed to run it 100% throttle for any extended period of time but since it's a stand up, you probably don't have to worry about that anyway. After the first tank I usually just give it the beans and ride it normal while still using 32:1 mix because it takes so long to run a tank through a stand up. After the second tank I go back to a nice synthetic oil and 50:1.
You're not supposed to run it 100% throttle for any extended period of time but since it's a stand up, you probably don't have to worry about that anyway. After the first tank I usually just give it the beans and ride it normal while still using 32:1 mix because it takes so long to run a tank through a stand up. After the second tank I go back to a nice synthetic oil and 50:1.
- Location
- Grand Rapids, MI
I prefer to ride it like I stole it.
- Location
- South Florida
Three questions:
1. What does breaking it in do?
2. What motor changes require a break in period?
3. What happens if you don't do it?
1. What does breaking it in do?
2. What motor changes require a break in period?
3. What happens if you don't do it?
Breaking in an engine basically seats the rings to the cylinder walls. Since nothing is perfect, there are tiny gaps between the walls and the rings that are filed away during the first few hours of riding. As long as you change the rings and/or hone the cylinder you should break it in again.
Now here's where the gray area is... Years ago rings and cylinder walls weren't machined with as close of tolerances as they are now so the break in is less important now than it was. Some can get away with not breaking in the engine at all and some will snag a ring or create excessive heat in the cylinder during the break in process and either destroy the engine on the first couple rides or potentially shorten the life of the engine. The heat is the biggest issue for not "giving it the beans" right off the bat.
Think of it like breaking in new brake pads to your rotors. If you go out in your car with your current brakes and tap the brakes lightly a couple times and stomp on them a couple times, nothing bad will happen. If you do that with brand new brakes and pull into the garage, your brakes will be smoking.
Since new pistons, rings, and a bore cost big money...I prefer to take it easy for a little while...just in case! What's a day or two of taking it easy compared to the time, effort, and money associated with tearing your engine down again.
Now here's where the gray area is... Years ago rings and cylinder walls weren't machined with as close of tolerances as they are now so the break in is less important now than it was. Some can get away with not breaking in the engine at all and some will snag a ring or create excessive heat in the cylinder during the break in process and either destroy the engine on the first couple rides or potentially shorten the life of the engine. The heat is the biggest issue for not "giving it the beans" right off the bat.
Think of it like breaking in new brake pads to your rotors. If you go out in your car with your current brakes and tap the brakes lightly a couple times and stomp on them a couple times, nothing bad will happen. If you do that with brand new brakes and pull into the garage, your brakes will be smoking.
Since new pistons, rings, and a bore cost big money...I prefer to take it easy for a little while...just in case! What's a day or two of taking it easy compared to the time, effort, and money associated with tearing your engine down again.
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- Location
- South Florida
So a used top end (pistons and cylinder), without a fresh hone, would not need a break in when attached to my lower end?
Correct
- Location
- Hokesbluff,al
break it in the way you intend to ride it. letting it run on the trailer for a few minutes is good while checking for any type of leaks. exhaust, gas, water etc. i also run the first tank with extra oil.
- Location
- Laughlin, NV
Riding or driving it the way your going ride it only applies to four strokes. If you have done that with a two stroke you have definitly shortend your engine life and got very lucky you did not seize your engine. If you have done a top end rebuild or just honed the cylinder and installed new rings it takes 30-45 minutes to break in. If you did a total rebuild ( new or rebuilt crankshaft ) I would run at least one tank of fuel for break in. And like the others said, break in with petroleum based oils only and vary the throttle during break in. You will be glad you did in the long run.
- Location
- Nova Scotia, Canada
Some people believe that the easy break-ins described here do more harm than good:
http://www.mototuneusa.com/break_in_secrets.htm
http://www.mototuneusa.com/break_in_secrets.htm
- Location
- Laughlin, NV
This is abosolutly correct.I guess what really needs to be understood with this topic is no wide open throttle riding during break in. The short hard accel runs are refering to once on a plane and riding, staying in the upper power range ( mid to peak ) and varying the rpms, occaisionally hitting wide open throttle but not holding it there for any length of time. Holding the throttle wide open during break for any long period will certainly to do minor to extensive damage to top end bearings and bottom end and main bearings on the crankshaft from heat generation due to friction from the bearings not being broke in. And the main bearings on the crankshaft take longer to break in properly ( reason for the longer break in on a complete rebuild ).