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Break in procedure after top end rebuild

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I need some help with the proper break in procedure after a top end rebuild.

I really do not understand thy"DRY" break in procedure and certainly none

of the manuals reference it. Longevity is my main concern. I want this to last,

I am doing new valve and spring kit, valve seats cut., new piston and rings,

and a new cam chain. Any advise would be greatly appreciated.

Thanks!!

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It's "dry assembly" - not dry break in.

Do a search on break-in and you'll find plenty of discussions about various approaches and philosophies.

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As far as i am concerned, ride it like you stole it for 5 to 10 minutes, let it cool then repeate a number of times, varry the RPMs, then change the oil. Mine has never burnt oil or lost any....

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I agree with Cavi...I used the hard break in method on my 250X and it's ran great for the 1500 miles of tight trails that i've put on it. It's never burnt oil, and i've never had any trouble other then the valves...which was my fault for installing an air filter wrong :applause:. My dad had his jaw gaping when he saw how i chose to break it in, so you will get some funny looks from the "non-knowers" if you choose the hardbreak in method :applause: But it'll run good :thumbsup:

Chris

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People have all kinds of ideas about how to break in a motor.

I have always felt that the key is more about the heat cycles and less about how many revs.

But here is what I do

Set up chair, umbrella and cooler with a good book.

Fire the bike up, let it idle with minimal throttle blipping and come up to operating temp.

Shut it off, have a seat, read your book and have a beverage.

When it has cooled enough to put you hand on the cylinder and not get burned then....

Start it up get it to temp and ride it no more than 1/4 throttle for 5 minutes.

Shut it off, have a seat read more and Drink lots of liquids. Getting the picture??

It helps to speed up the cool down if you can put a fan on the bike if you have power.

Do that cycle at 1/2 throttle, 3/4 throttle and then with full throttle runs.

After the last cool down session you are ready to roll.

It has worked for every Dirt Bike, Street Bike, and Jet Ski motor I have ever built.

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Thanks for the tips every one!!!

When we say dry assembly,what exactly are we talking about?

I have been told to hone the cylinder with a ball hone but the manufacturers

instructions that came with the piston say never to use a ball hone on a plated cylinder?!!

Actually the cylinder looks good with the original cross hatch pattern still

showing.

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If the cylinder has no glazing leave it alone. (Although if you have a nikasil brush you can use that)

Wash the cylinder and piston with hot soapy water. Dry with clean cloth.

Then I wipe them down with brake clean. Do it again and again with white paper towels until the towel comes out clean! (trick from old drag bike builder in Chicago)

Here I use a semi dry assy. I wipe down the piston only with a little oil and wipe it till it feels dry. ( I feel it gives the skirt a small amount of lube during start up)

Assemble the rings and the cylinder then follow my or your break in procedure.

Thanks for the tips every one!!!

When we say dry assembly,what exactly are we talking about?

I have been told to hone the cylinder with a ball hone but the manufacturers

instructions that came with the piston say never to use a ball hone on a plated cylinder?!!

Actually the cylinder looks good with the original cross hatch pattern still

showing.

:thumbsup::applause:

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