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New kx450f dyno

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Hey guys so i just picked my new kx450 which im stoked about. I have never broken in a dirt bike as the manual suggests before. But then one of my friends told me that it was super important! I thought they broke them in on a dyno at the factory and the dealer rides it to see if everything is as it should be. I didn't break this bike in. Im 17, race and ride my bikes pretty hard and would really not like to dish out a load of money to get it rebuilt 10 months before if i broke it in. Any mechanics or gurus have any advice? Im really paranoid. Thanks guys

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Bikes are typically never run until the 17 YO kid who does the sweeping and the uncrating at the dealership fires it up for the first time after hopefully fully bolting the front wheel on and putting oil in.

Google Mototune though if you bike has more than ten minutes run time already, the break in period is over. Unless you are a top level rider, the break in is not critical. Do the first oil change, fresh oil filter, clean the screen after the first couple of hours. Go over all the fasteners CAREFULLY. Put anti-sieze on every spoke. Re-spring for your body weight and riding style.

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1 hour ago, skorpan777 said:

Don't use Mototune break in method 

Use your manual and do what they says. 

Thats the best thing for your bike, and you! 

How come? Have you had a bad experience using their method?

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12 minutes ago, Heidonkx said:

How come? Have you had a bad experience using their method?

I know his wrong in his approach. 

I've read most of his"ideas" so I know his wrong but you must read all on his website and have a good understanding on engineering/manufacturing  to understand why his is wrong. 

For normal person, he sounds pretty smart because it sounds logical......but wrong. 

I suggest you to read it. 

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2 hours ago, William1 said:

Bikes are typically never run until the 17 YO kid who does the sweeping and the uncrating at the dealership fires it up for the first time after hopefully fully bolting the front wheel on and putting oil in.

Google Mototune though if you bike has more than ten minutes run time already, the break in period is over. Unless you are a top level rider, the break in is not critical. Do the first oil change, fresh oil filter, clean the screen after the first couple of hours. Go over all the fasteners CAREFULLY. Put anti-sieze on every spoke. Re-spring for your body weight and riding style.

Thanks for the input. So hes probably broken it in already? Do they normally get fired up at the shop?

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The fact that the Mototune method doesn't destroy engines is merely a testament to the quality of the engineering and manufacturing that goes into these motors.  They have managed to mass produce a high performance engine that even the most hamfisted, misinformed buffoon cannot immediately destroy. 

Stick with the factory recommendations. 

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5 hours ago, Heidonkx said:

Thanks for the input. So hes probably broken it in already? Do they normally get fired up at the shop?

Yup. Typically, a dealer has to follow a PDI sheet (which you should of gotten a copy of) that is a 'confirmation' that they checked everything specified by the manufacturer. They put fuel in (a gallon) and run the bike, to ensure it operates.

Sometimes, it is just a slow putt through the parking lot, sometimes the PDI guy will run it hard for a few minutes before washing. There were times in my youth were we'd take new MX bikes out to a field and run 30 minutes of flat tracking, betting n how long you could go sideways with both feet up on the pegs. We never delivered a bike with nubbies on the tires ;)

Modern bikes, the tolerances are so good, all that really needs to be done the is the rings bedded in. So a medium hard running causes the combustion gases to force the rings against the barrel walls before and glazing can happen and ensure a good seal. Though for the typically buyer, the difference in performance between a perfectly broken in (ring set) engine and one not done well is not noticeable other than premature oil consumption (say at 100 hours instead of at 150) things a hard core rider/racer would not worry about because they replace rings and such often (based on results from regular leak down tests.

Many manuals have break in instructions that were written for machines designed in the 1960's. It is also a safety net for the manufacturer incase of engine failure to make it easier to blame the owner for a problem. The reality is, you have an all out race bike and as such, it is expected to be run at the track ASAP.

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1 hour ago, William1 said:

Yup. Typically, a dealer has to follow a PDI sheet (which you should of gotten a copy of) that is a 'confirmation' that they checked everything specified by the manufacturer. They put fuel in (a gallon) and run the bike, to ensure it operates.

Sometimes, it is just a slow putt through the parking lot, sometimes the PDI guy will run it hard for a few minutes before washing. There were times in my youth were we'd take new MX bikes out to a field and run 30 minutes of flat tracking, betting n how long you could go sideways with both feet up on the pegs. We never delivered a bike with nubbies on the tires ;)

Modern bikes, the tolerances are so good, all that really needs to be done the is the rings bedded in. So a medium hard running causes the combustion gases to force the rings against the barrel walls before and glazing can happen and ensure a good seal. Though for the typically buyer, the difference in performance between a perfectly broken in (ring set) engine and one not done well is not noticeable other than premature oil consumption (say at 100 hours instead of at 150) things a hard core rider/racer would not worry about because they replace rings and such often (based on results from regular leak down tests.

Many manuals have break in instructions that were written for machines designed in the 1960's. It is also a safety net for the manufacturer incase of engine failure to make it easier to blame the owner for a problem. The reality is, you have an all out race bike and as such, it is expected to be run at the track ASAP.

Wow thanks for such a detailed reply! I massively appreciate it! You seem to really know your stuff so perhaps i could ask one more question? When kick starting a bike, some manuals (not all) say that you should move the kick lever down until you feel resistance. Is that because if you kick from the top (where its loose) you can damage it?

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2 hours ago, Heidonkx said:

Wow thanks for such a detailed reply! I massively appreciate it! You seem to really know your stuff so perhaps i could ask one more question? When kick starting a bike, some manuals (not all) say that you should move the kick lever down until you feel resistance. Is that because if you kick from the top (where its loose) you can damage it?

Yes, sort of.

Typically, you PRESS the kicker start lever until you feel stiff compression. Then bring the lever back up and with a smooth and even PRESS, run the lever through its' full movement. Do not 'jump on the lever' applying force all at once, you press it like squeezing a trigger.

The damage you have heard of is from guys jumping on the lever like they were kicking a mule.

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18 hours ago, Heidonkx said:

Thanks for the input. So hes probably broken it in already? Do they normally get fired up at the shop?

The are not broken in , because it need liitle  time. You never know how the dealer does

So do the proper breakin according to the manual its the best. No more No less

Edited by skorpan777

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