[dmstarr]

Breaking in a new KX100 from the showroom floor. After greasing it up, oiling the air filter, checking all the faserners/spokes/etc, what do yoou recommend for a break-in?
I plan to do it just like a top end. Idle untli warm, kill, cool. Repeat. Small blips, cool. Check torque. Ride with less than 1/4, then one half throttle. Cool. Check torqe, and let it go. Sound about right?

 

[520KLX300R]

I did break in just like you plan and all is well with my KLX. By the book a guy can't go wrong imo.

 

[FPMXer]

I do two complete heat cycles and then ride it in a higher gear and under load to help seat the rings. Haven't had a failure yet.

 

[YurFatMom]

I do two complete heat cycles and then ride it in a higher gear and under load to help seat the rings. Haven't had a failure yet.

Ditto.

 

[griffbones]

I normally perform 3 or four heat cycles.
Easy ride for ten minutes, complete cool down
Easy ride for 20 minutes, complete cool dwon
Then one last easy rde for about thirty minutes and complete cool down.
Then change the tranny oil if it is a new bike, and not just a new top end. Check the spark plug and go ride the heck out of it.

BTW, my easy rides are basically normal riding, just keep varying the speed and load on the engine, and keep it under half throttle for a little while, and then under 3/4 throttle for a little while.

If the bike is new and all stock, you may have to lean the needle out one clip postion as the KX100's seem to be very rich in this area from the factory, the main and pilot jets will probably be ok until summer depending upon your local temps altitude and humidity levels.

If you ever have a cylinder replated with NICOM and have it honed so that you have some nice cross hatching (unlike the stock Kawi cylinders) the rings will basically seat after about three heat cycles, much faster than on the stock Kawi plating.

 

[dmstarr]

what about the guys who swear that riding heard after the first heat cycle is the only way to properly seat the rings?

 

[FPMXer]

This is a long and on going debate about what is the best way to break in a bike. I have heard/read people saying that as soon as the bike is started the rings seat to the cylinder. I have also heard you should ride a full tank of gas real easy. The way I splained it is the way I do it without issue. Take what we all suggest and do it how you want to. It's safe to say that as soon as it starts don't ring the snot out of it or it will burn the coating off the rings.

 

[dmstarr]

I hope y'all don't think I was questioning your methods...that is why I ask here. There are many helpful posters. I just heard about the "hard" break in recently, and was intrigued. I think I'll stick with tried-and-true. Never lost a piston or a ring yet, but I do get more blow-by on the piston than I care to see.

 

[griffbones]

I hope y'all don't think I was questioning your methods...that is why I ask here. There are many helpful posters. I just heard about the "hard" break in recently, and was intrigued. I think I'll stick with tried-and-true. Never lost a piston or a ring yet, but I do get more blow-by on the piston than I care to see.

If what you are seeing on the piston is on the exhaust side, this is normal, and not blow by.

 

[dmstarr]

Thanks, Griff. I'll double-check it when I get home. That would ease my mind. Of course, since it's already apart, I'm gonna replace it with a new piston anyway.
Speaking of which...what is the best way to remove the wristpin? I've always tapped it out with a hammer and punch, but in hindsight, probably not the smartest thing to do, sending lateral shock to the crank.

 

[KickassKX125]

I ran my bike in on the stand by running a full tank of fuel through and varying the throttle between idle and WOT then riding it hard and I've just done my 2nd top end this year and all i needed to do was fit a new head gasket because the rings where fine, although it will need doing soon because the barrel needs replating.

 

[griffbones]

Thanks, Griff. I'll duoble-check it when I get home. That would ease my mind. Of course, since it's already apart, I'm gonna replace it with a new piston anyway.
Speaking of which...what is the best way to remove the wristpin? I've always tapped it out with a hammer and punch, but in hindsight, probably not the smartest thing to do, sending lateral shock to the crank.

If you support the crank that is fine, but if the pin is really tight you need to use a wrist pin removal tool. Motion Pro sells the tool and you can get them through a dealer or even off of Ebay, they aren't very expensive. Normally I can get the pin out with out too much fuss, although the Wiseco pins tend to get tighter than the stock pins for some reason.

 

[YurFatMom]

^You can also remove a stuck wrist pin with a bolt, some washers, and a socket.

 

[griffbones]

^You can also remove a stuck wrist pin with a bolt, some washers, and a socket.

+1 This is basically how the removal tool works.

 

[dmstarr]

^You can also remove a stuck wrist pin with a bolt, some washers, and a socket.

tell me how you guys do this...sounds interesting

 

[YurFatMom]

Find a bolt that will fit through the wrist pin, and so the head can fit through the piston's wrist pin whole but so the bolt head will rest on the pin. Put a big soft washer on the bolt after it has been inserted in the wrist pin. Now, get a socket that will fit over the bolt and that the wrist pin can go inside of. Put the socket on the bolt, put a washer on top of that, and then a nut. Tighten the nut up, and out comes the pin.

 

[ervins]

Total newb to this since I am getting a dirtbike this weekend...You mean I just don't fill it up and start riding? I have to do some waiting? When I got my ZX-10R I just filled it up and started flying....Going through gears and just just making sure not to be at a certain RPM too long...When I get the TTR this weekend can I just do what I described?

 

[griffbones]

A Yamaha TTR will be no problem for you, just ride it easy for a little bit. The TTR is a four stroke play bike, very simple and very reliable, so just ride it and have fun!

 

[YurFatMom]

Be nice to it for about 5 hours, and then commence the beating.:biggrin:

 

[dmstarr]

awesome. thanks, guys.