I wrote the following piece regarding breakin of SPECIFICALLY modified 400L Polaris engines - :-)

"After washing your cylinder on your Polaris with HOT SOAPY WATER , install it with your new piston assembly and gaskets . If the bore was done properly breakin is almost always a succes if you follow these suggestions .

If you have made modifications at the time of boring richen your mainjet and needle settings to a point where it is almost certainly to rich . As you start breaking in you can lean it out as needed to get the mixture correct .

Start the engine and let it idle just a couple minutes as you look around for coolant leanks and what not . At this point find a small piece of property to ride on , the reason I like a small piece of property is so that you are constantly turning around which means you have to be on and off the gas . Make a few 10 minute runs allowing the quad to cool for 10 minutes inbetween the runs . Do this till you get about a half and hour on the quad . If the quad is noticably way to rich you may begine to lean things out one size or one setting at a time .

Still being mindfull of getting the engine to hot or under to much strain , you can run the quad now in 15 - 20 minute intervals .

After 2 hours you can start getting a little braver with the quad but still do not try to cruise down long roads or staying hard in the throttle for over 150 feet . Keep your jetting a little rich still , don't try to fine tune it til after 3 hours .

After three hours , and you feel that you have the richest carb settings that the quad will handle you can "let 'er have it " . Your have successfully put your quad back into service . Now is a good time to check torque on all the head and base bolts when the engine cools . Also during the entire break-in , keep an eye on the radiator , be certain the head gasket is not leaking or you will be back in the toolbox and wallet again .

I am sure you all have heard and read all kinds of ways to break-in and engine , the " Break it in fast and it will be fast " method is many times a certain doom for a 400 polaris . If you want to do this - be my guest - but if it is in my shop getting bored , let me know , I will loosen the clearances a bit so you at least have a chance . I prefer a little snugger bore and a more easy approach to break-in on a Polaris , this will get you a longer lasting rebuild because you have more material to wear before service is needed again . Don't worry about the *glazed clylinder * and *the rings didn't seat* - on the 400 polaris this is simply nothing to be concerned with . "

Rick

 

DoctorTurbo, you're right in one thing. <u>Both</u> opinions are still unsubstantiated.

Both opinions are based on anecdotal experiences and remain that way without facts. Again, there are no FACTS presented, only opionions. Either way, we have different experiences with similar results. Good running engines..

I've too have been down the racing route for years (1958-2002). My companys AA/FC ( thats a blown nitro burning funny car for the round D round guys) "Pacemaker Vega" won the Indy Grand Nationals in '72 or '73 and held the ET & MPH record for a while.

 

Goof post RickRitter.

 

<div class="FTQUOTE"><begin quote>Originally posted by: RickRitter

I wrote the following piece regarding breakin of SPECIFICALLY modified 400L Polaris engines - :-)



"After washing your cylinder on your Polaris with HOT SOAPY WATER , install it with your new piston assembly and gaskets . If the bore was done properly breakin is almost always a succes if you follow these suggestions .



If you have made modifications at the time of boring richen your mainjet and needle settings to a point where it is almost certainly to rich . As you start breaking in you can lean it out as needed to get the mixture correct .



Start the engine and let it idle just a couple minutes as you look around for coolant leanks and what not . At this point find a small piece of property to ride on , the reason I like a small piece of property is so that you are constantly turning around which means you have to be on and off the gas . Make a few 10 minute runs allowing the quad to cool for 10 minutes inbetween the runs . Do this till you get about a half and hour on the quad . If the quad is noticably way to rich you may begine to lean things out one size or one setting at a time .



Still being mindfull of getting the engine to hot or under to much strain , you can run the quad now in 15 - 20 minute intervals .



After 2 hours you can start getting a little braver with the quad but still do not try to cruise down long roads or staying hard in the throttle for over 150 feet . Keep your jetting a little rich still , don't try to fine tune it til after 3 hours .



After three hours , and you feel that you have the richest carb settings that the quad will handle you can "let 'er have it " . Your have successfully put your quad back into service . Now is a good time to check torque on all the head and base bolts when the engine cools . Also during the entire break-in , keep an eye on the radiator , be certain the head gasket is not leaking or you will be back in the toolbox and wallet again .



I am sure you all have heard and read all kinds of ways to break-in and engine , the " Break it in fast and it will be fast " method is many times a certain doom for a 400 polaris . If you want to do this - be my guest - but if it is in my shop getting bored , let me know , I will loosen the clearances a bit so you at least have a chance . I prefer a little snugger bore and a more easy approach to break-in on a Polaris , this will get you a longer lasting rebuild because you have more material to wear before service is needed again . Don't worry about the *glazed clylinder * and *the rings didn't seat* - on the 400 polaris this is simply nothing to be concerned with . "



Rick</end quote></div>


this is the same basic stuff that our engine builder tells us. and i am still basing this on 2 strokes because what i have was originaly a 250 cc honda dirt bike engine. and on our dit tracks it is an oval you are full throtel threw every gear untill you hit 5th into first turn in teh midle let off for a split second downshift to 4th back to full then let off for a split secongd upshift to 5th you throw the car in right and keep the engine wound out.

 

Everybody knows you're supposed to follow the correct break-in procedure. One good reason is because of the amount of friction between the rings and cylinder before the rings seat. There's a lot of heat in there and the oil isn't necessarily all in the right place since the rings aren't spreading it around evenly or stopping it from blowing by. Two things that take the life out of an engine are friction and heat. You get plenty of both without pushing your luck.

 

I get the feeling this discussion could go on for ever and never reach a conclusion...I guess we are all free to make our own decision!

 

<div class="FTQUOTE"><begin quote>Originally posted by: jokout

I get the feeling this discussion could go on for ever and never reach a conclusion...I guess we are all free to make our own decision!</end quote></div>

Yep. But I figure if you didn't need to break it in, the instructions would be more like.. go tear it up, run WOT until it's out of gas, don't change the oil, just replace what burns up...

 

<div class="FTQUOTE"><begin quote>Originally posted by: jumbofrank

<div class="FTQUOTE"><begin quote>Originally posted by: jokout



I get the feeling this discussion could go on for ever and never reach a conclusion...I guess we are all free to make our own decision!</end quote></div>



Yep. But I figure if you didn't need to break it in, the instructions would be more like.. go tear it up, run WOT until it's out of gas, don't change the oil, just replace what burns up...</end quote></div>

That's what my manual says go tear it up run it wide open till you hear a pop ..........that will be the last time I buy a POLARIS manual from the HONDA DEALER I DO NOT CARE EVEN IT WAS ON SALE! I guess I should have known something was up when it was wrote in crayon......oh well live and learn....[img]i/expressions/face-icon-small-happy.gif[/img]

 

Alpine2 - that's funny