Breaking bike in tomorrow? Questions, Thanks

[Mataz]

Hello

I bought an 06 yz450, I currently have a 94 kx 250 (I'm sure it will be like night and day better) I've been lurking on the forums for a couple of years, and wasn't even sure if I was going to buy a four stroke, but this will be my first four banger I planned on getting a crf450 (which I'm sure I would be happy with) but decided to go with the yamaha thanks to all the good things I heard from you guys. (valve train, suspension, and so on) I've followed your guys recommendations, raised the forks, got a new front tire, a gytr air screw, jetting)

I bought a 48 pilot jet (turned out the shop gave me the wrong one) and put in the 170 main. Should I bother even breaking it in tomorrow, temps will be in the upper 50's to 60 degrees. I've waited this long. I can wait another week. I'm concerned about riding it with the stock pilot jet. I want to do the right thing. (I'm a little nervous being my first four stroke)

But I want to thank you guys for all the great info over the years.

[mkporn]

Glad to see another convert. Are you sure that your bike is jetted improperly to begin with if you have not even broke it in?

What is wrong with breaking it in those temps?

First off (i know someone will say bull, but) Your bike is more than likely close enough jetting wise to ride it with out problems period. These things are jetted a little fat from the fatory at sea level and an average temp.

Put everything to stock, fire the bike up and let it warm up and take it for a short spin, no full throttle, just mid throttle and run thru the gears up and down and operate the brakes and get a feel for it. After ten or so minutes, shut it down and put it on a stand to cool and to check all the nuts and bolts on it.

Now get on it and ride it, not excessivley agressive, but ride it (this does not mean jump on it cold, fire it up and hold it fifth tapped). Ride for a while, go back to the truck and check everything out. Give it a few and go bang around again.

Now take the thing home, change the oil and filter, clean the air filter and tighten all the nuts and bolts and make sure your spokes are tight.

Now when you are sitting there thinking about how great the ride was and how happy you are, pick up the owners manual and read it, set it down and read it again. Then pick it back up and read what it say's about adjustments of the suspension and carb.... And figure out how far off your jetting really is.

I am always amazed how people can tell other people what to run for jetting without knowing anything about thier area. Temp, altitude, fuel and mods have tons to do with jetting and just throwing jets at a bike because that is what so and so said is not the best solution.

congrats on the new bike

[barch88]

Read your manual. It has "Break In" right after Cleaning and Storage section, Im not 100% sure on the page number now because Im at school, but I know its towards the front. I followed those steps in the manual as far as break-in goes. Then after break-in I changed the oil and oil filter, then rode a little more the next day, and changed the oil once agian, along with one last fresh oil filter (Just to be safe my break-in's complete). The 2nd day I made sure to hit 5th gear with mine, just to get it through all the gears. First day I was on a small track and only hit 4th for a second.

Before you go ride it, tear apart all your linkage, GREASE the bearings, tear apart your steering stem bearings and pack those full of grease, and do both axles, along with both wheel bearings. Me and my Dad ripped mine apart and they was near nothing in there, we packed soo much grease in them, they took A LOT of grease. If you don't know how, theres GREAT articles on Transworld Motocross.com that show you how and also tell you to grease your new bike because theres close to none in it. I printed up 3 of them on the greasing, and one on jetting.

Other than that I love this bike. The stock Jetting didn't work for me and I broke it in with the stock, as it was popping on decel, which is a result from a lean mixture. Now my bike won't even start (fouled plug) so Im going to also change my jetting to the 48 pilot jet, as everyone else did, and as Burned suggested for me. Chances are it will be too lean for you too with the stock, so you should be fine since you already changed it.

The bikes sick, have fun man! I recommend picking up a new chain, skid plate, radiator braces, other than that the bikes perfect out of the showroom. Before I ride agian Im going to be picking up those parts, stock chain streches a ton so I hear, and after my break in I noticed it did strech.

[ben_suhard]

Hello

I bought an 06 yz450, this will be my first four banger

It's actually a one banger(one cylinder). You should be ok to ride it this weekend, I know what you mean about not wanting to wait. I rode mine for the first time at sea level with the stock jetting, and it ran fine apart from the backfiring when the throttle was closed. I've rejetted it richer for the coming weekend; I don't want to run the risk of it running too lean and detonating. I went with mototuneusa.com 's break-in method (except for using the car oil). He reckons to ride it hard on and hard off to seal the rings better, so I did that, I rode it hard but avoided revving it too high.

[ovrrdrive]

Damn... I was going to say that as soon as someone mentions mototune to run like hell the other way but I'm too late...

Break it in the tried and true way that's detailed in the manual. The guy at mototune is a quack - in my opinion. There's no way that one guy could find so many overlooked secrets that every other mechanical engineer in the world missed...

You spent too much money on it to take the chance.

[barch88]

Damn... I was going to say that as soon as someone mentions mototune to run like hell the other way but I'm too late...

Break it in the tried and true way that's detailed in the manual. The guy at mototune is a quack - in my opinion. There's no way that one guy could find so many overlooked secrets that every other mechanical engineer in the world missed...

You spent too much money on it to take the chance.

Exactly. I ran the manual's break in and trust me, I don't think I lost any power out of this beast.

[NOMADAK]

A word of caution. The 42 pilot(stock) in this bike is VERY lean at near sea level altitudes. With cooler the temperatures you are experiencing in Michigan, expect the bike to pop alot especially on deceleration.

Running lean means running hot.

I don't know if I could resist (and I couldn't with mine) but a short break in ride with the stock jetting isn't going to damage the motor. Run it.....but change the pilot out as soon as you get the 48.

[barch88]

A word of caution. The 42 pilot(stock) in this bike is VERY lean at near sea level altitudes. With cooler the temperatures you are experiencing in Michigan, expect the bike to pop alot especially on deceleration.

Running lean means running hot.

I don't know if I could resist (and I couldn't with mine) but a short break in ride with the stock jetting isn't going to damage the motor. Run it.....but change the pilot out as soon as you get the 48.

Yep! I live in Michigan, and ran the stock 42 Pilot jet with my 3 hour break-in, lots and lots of popping. I now bought a 48.

[Mataz]

Well guys, I rode it today (at the Martin track) rained all the way there but that tracks real ridable muddy. Man, I had a hell of a time starting it, I was afraid to give it to much gas, didn't want to flood it.( my first time starting the bike) I've learned that you have to give a touch of gas when starting it. The bike HAULS. My KX has no low-end, so it's nice to ride a bike that pulls from down low. The suspension feels great, and I still need to set the sag. The bike ran great, NO backfiring at all. If it was doing it, it was so subtle. This bike has balls The bike leaked a bit of coolant out of the over flow tube before the first ride, but never after that. I have an o-ring and a new front tire to put on, but will wait a bit to see if I'm happy with the stock gearing.

mkporn, barch88, ben_suhard, ovrrdrive, NOMADAK. Thank you guys.

[beezer]

I'm glad you like your new bike. Yamahas are very reliable bikes so breakin isn't a big concern but most newer bikes run better if broken in hard.

I go over my bikes before I even start them. I grease the linkage and the steering head bearings and check the nuts and bolts. Then I start the bike up and ride it around the house and change the oil and filter.

Then I ride it like it isn't mine.

[barch88]

Well guys, I rode it today (at the Martin track) rained all the way there but that tracks real ridable muddy. Man, I had a hell of a time starting it, I was afraid to give it to much gas, didn't want to flood it.( my first time starting the bike) I've learned that you have to give a touch of gas when starting it. The bike HAULS. My KX has no low-end, so it's nice to ride a bike that pulls from down low. The suspension feels great, and I still need to set the sag. The bike ran great, NO backfiring at all. If it was doing it, it was so subtle. This bike has balls The bike leaked a bit of coolant out of the over flow tube before the first ride, but never after that. I have an o-ring and a new front tire to put on, but will wait a bit to see if I'm happy with the stock gearing.

mkporn, barch88, ben_suhard, ovrrdrive, NOMADAK. Thank you guys.

Glad you had fun. If you havent already now, grease your bike up. Also, DO NOT give it gas when starting it. It says right in the manual not to, it isnt like a 2-stroke. Just pull the choke out and you should be good. Coolant should puke out when just on idle, because the bike is overheating, its normal.

-Mike

[Mataz]

beezer, barch88, thanks guys. I'm going to tear it apart and grease the linkage this week, steering stem to follow, and change the oil and filter.

Coolant should puke out when just on idle, because the bike is overheating, its normal.

Man, that's stuff I have to get use to. The bike smelled a little warm (I think any oil, or what not on the pipe being new was burning off. I can't wait to get more time on the bike

[barch88]

Yeah, you can just smell and feel the heat coming off the pipe, it should turn blue. How was the jetting for you?

Make sure to lube all your wheel bearings and axles while your at it too.

Have fun with it!

[Mataz]

How was the jetting for you. It seemed good, no popping. It was around 60 degrees, so if it's not doing it now, I'm guessing it will be fine as it gets warmer out. Are you able to grease the wheel bearings, aren't they sealed?

I'll put a coat of grease on all the axles, makes it nice when you have to pull them out in the future. Here's a pic before I got it dirty.

[Drfletcherdc]

Make sure you check your spokes after riding. Almost everyone of mine were loose. I also still have to give it a touch of gas when starting, but at least you don't have to kick it hard like a two stroke.

[Mataz]

Thanks Drfletcherdc.

I'll check them before my next ride.