IMPORTANT 2 stroke tips / Piston Lubrication holes CR250 

Im not very good at speaking english but i tried my best, lol! Hope you understand what i try to tell you :)

Hello Nice Video That was great information, I used to Race a Kawasaki 750cc 3 cylinder and I wish I had that info back in the 70's It would have saved me some trouble then. That exactly is what happened to my Bike then, It was the center cylinder (It always ran hotter than the other 2) that one had that problem, I used Weisco Forged Alum, Pistons, What I did to remedy that problem was to use an indexing tool to mark out a series of drill points all the way around the piston about .500' apart (I cant remember exactly but just do the math for the pattern) and .500 lower stagger the indexing marks to land in between the first row and continue stepping the marks all the way down on the piston, (I had a friend with a machine shop , that made it easier) When that was done I used a .250 Drill and started the first pocket but drilled only to the depth of the angle on the tip of the drill, I set the depth on the Drill Press so the rest would be the same, and followed every mark at that depth all the way to the bottom of the piston, Not only were the pistons beautiful when finished but they balanced out almost perfectly and all Cylinders ran cooler (Compression was not effected, Slight increase in RPM's And it would get to maximum RPM's faster. The end result was a lighter piston with less friction and more lubrication on the Cylinder walls with less friction, That worked well for me, Never had a problem after that, I Hope you can use this to your advantage. Oh and they really are beautiful when finished. Be Well my friend, I like your way of presenting your video , That's why I am sharing this with you, I'm old now and don't want to go to my grave without sharing my trade secrets to anyone! Hope you liked it ! Ron Nadeau

wow thanks for info. ive cracked 2 cylinders right where you showed it cracked and never have known to do this til my friend told me the other day to drill holes and then i came across this vid. i have same bike 03 cr250 and just bought new cylinder and wiesco piston and am looking forward to having a reliable machine.

Thank you for this video, you explained why this is necessary for cylinders with Exhaust Bridges better than Wisecos instructions 👌🏻😊

For everyone wondering, drilling theses lubrication holes will not effect your compression as the holes are drilled after the piston rings. Basically the intent is to cool down your Exhaust bridge meaning that you wont have as much wear on your piston and over all you'll have less issues in the future. Great video!

This is correct, my machine shop explains it to me so I let them do it , they know more about this than me, I haven’t had any issues and glad they did it

surely if it was such a big problem,then they will make pistons with the holes already drilled out,never been a problem with me and my bikes.thank you.

Hello, the video was excellent and helpful . Question What is the reason for using these pistons and not others?

Thank you so much! I have had questions about these piston holes but thatnks to this vid i now understand!

You should make a video on a cr125 power valve... I’d love to know how to get the thing off and on again.

Du er nødt til å være Norsk du :) Kjempe flott film du har laget her. lett å skjønne å veldig enkelt å følge med på. Bra jobbet.

G'day do you think this would work on a chainsaw piston? given that a chainsaw is flat out all the time when working hard, I have found a lot of cooked saws that this might of fixed so I will try it out. Great video out of the box for thinking cheers Kevin

My piston is cast and is perfectly fine with 4 drilled holes like the ones you showed.

Can you drill through a vertex piston. Someone pls tell me I'm rebuilding my bike soon and I dont want to make the wrong choice

Nice info . Thanks mate nice vid too!

Good info mate beautiful bike's keep them hummin

I need a stroker Crankshaft For 99 Honda CR125R could you advice where can I get it. Thanks

Hi Frez, do you know if I have to drill my piston in case of sleeve cylinder ? Or if it's just for Nikasil application and alloy monobloc cylinder? Thank you

Nice video homie

and without exhaust bridge?? can u also drill holes for those cylinders?

Should you do it on Vertex piston?

what 2stroke oil are you using and at what %/ mixture do you blend it ?, Awesome video!

WHEN YOU DONT HAVE A BRIDGE THE HOLES CAN ALSO HELP LUBRICATION AT THE HOT EXHAUST AREA

VERY GOOD VIDEO THANK U

what about vertex pistons

do you know if my 2001 cr500 motor has a bridged port ?

In the kawa kx 250 dont is need drill holes on piston my cylinder dont have exhaust bridge

.300"- how much is this in millimeters?

Why do they use exhaust bridges?

I've never had a problem

All the years ive been riding cr250's ive NEVER had to drill any holes in the piston. There is no need to do this, as long as you maintain your bike properley and always warm your bike properley and use the correct oil/fuel mix you never ever need to do this.

👍

Soo why does not the manufacturer off pistons and maybe the whole Engine,drill this holes if there are so necesery ?? Hard to belive that it is a costthing when the only thing you need is a drillbit and a drillmachine and woluld cost a bout 20 dollar extra in workpayment to according to you save a lot of Engines from seize.

Why don't pistons just come with it

i have come here to defeat you ricky bobby-

Keep the piston lubricated? Just take the spark plug off, and pour 2 stroke oil down the piston and cylinder, that also helps keep it lubricated and last longer

good vid, but I think everyone knows this, maybe I'm wrong...

its such a shame that Honda shit canned their new crank case engine the 05 on is a work of art, it just did not get the dollars needed to make it better and better by year by year.

I think you should of explained in the beginning , that this only applies to forged pistons. What a waste of time listening so far in only to find out it doesn’t apply to my bike.