PW50 Mod, Install of 60cc Bigbore Kit

[@sirjolly81]

Normal Engine oil is best for a new cylinder. Assembly lube can stop the rings from creating a good seal. But great video and going to upgrade the kids pw50 once he gets more confidence.

[@joellaurin9007]

Im doing a block off plate and single throttle cable. Also a top end with Yamaha OEM Std size cylinder and piston etc. Im going to reuse the head.

[@azgrandpadon6186]

@ 14:56 The correct torque is 84-88 in/lb, not 88 ft/lb.

[@TheDanno81]

The piston in the pw50 I have looks just as scored as the one out of your bike. Turned out to be the boot between the carby and the airbox slipped out of the airbox and was sucking grit in. I had to flush out and blow out the crankcase and order a rebuild kit. Certainly something to keep an eye on.

[@bigair0176]

Ya thanks. I suspect all the damage that was done was before I got the bike. I make sure there is no air leaks for sure. Hope your big bore working good. Mine fired right up first kick. I did my own deglazing of the cylinder too. Cheers!

[@zachskeen7611]

Great video, just bought one for my boy, I was reading the comments I know you don’t have the bike anymore but did you adjust the carb to make it run more lean, or how did you fix that issue?

[@bigair0176]

I installed an aftermarket air filter. The jetting is rich for stock so I just kept the 70 main. You can make some adjustments with the pilot screw to make it leaner or richer. I have a vid on my channel on adjusting the carb along with a whole bunch of other pw50 vids. Hope this answers your question.

[@iainf]

Just spent an age researching this-what you need is a zinger yt60 carb & the only difference is the main jet at 92.5 or run a 0.9mm jet through the std pw 0.7mm jet. 👍

[@bigair0176]

@@iainf problem is tho hard to find a carb like this. I thought about it. Ordered one from pwonly and it never showed up.

[@iainf]

@@bigair0176 Run a 0.9mm drill bit through the jet. 👍

[@michaelfunston5555]

@Bigair01 pwonly went waaay down hill. Started using Pax Racing for all my upgrade mods. Little bit more pricey but they have huge selection of parts, the guy is super knowledgeable, and customer service is great.

[@Mjlenard]

Great video. Just put my piston kit on my Y-zinger. Hoping it will hold up.

[@bigair0176]

Nice. Thanks for watching!

[@deerslayer4331]

A scored piston is not much of an issue it's the fact that the cylinder walls are scored, the rings are larger than the piston and make the actual seal with the cylinder walls.

[@billblass5961]

Good job, I'm about to do the same. Thanks! Be sure and check for lower, big end bearing play during this mod. If it's worn, replace it now.

[@bigair0176]

Thanks! I checked it and didn’t seem to be any play. I was a little skeptic all on these cheap kits. But all in all super impressed how it runs compared to before. Was in dire need of a new top end as you saw the piston I pulled out lol. Cheers!

[@Lilhombre-2]

@@bigair0176 nice!! what year pw you working on? my son has a 2019 and I wanted to get him a kit just didn’t know which to get. I like how you explain as you go so when I do get it I’ll look back at your vid!!! great vid 👌

[@bigair0176]

@@Lilhombre-2 this is a 1983. I’ve got about ten vids I have done so far on the pw50 on its restoration. Thanks for the feedback. Cheers

[@edh4686]

Hello I have a questions for you? Have you noticed a bigger performance boost out of to he p we 50 since you've done the Big bore kit and the new reads and exhaust. Great videos thanks.

[@bigair0176]

@@edh4686 compared to the way I got it. Heck ya. This bike is crisp and even pushes me along. I would say the big bore kit and reeds are a start and if you want a better sound do the exhaust. The exhaust helped lean it out a bit cause the stock 70 main jets certainly can play a factor. I was going to try the 65 main like allot of people were saying to do. But the bike starts and runs so good as it is.

[@joseacarranzah7488]

Thanks. Your video was very helpful.

[@bigair0176]

Awesome. Glad to help. Cheers!

[@Weldzzz]

Just picked one up yesterday how’s the kit working for ya ?

[@bigair0176]

Kit worked great. Just make sure you get a good deglaze and cross hatching going on. It will help with your breakin. My kid has outgrown the bike and I don’t have it anymore. Cheers

[@gwade8808]

Did you just use a bore brush to get the cross hatch?

[@murph2521]

My bad you posted this 9nly 3 months ago. I assume its still running. I thought this video was a few years old for some reason lol

[@jprracing4907]

Great video, I will be doing the same to my sons and we will be putting the race head and fmf exhaust. Was there a noticeable power difference after the rebuild?

[@bigair0176]

Heck yea! I wish I did it way sooner for him. Cheers!

[@caleb7194]

What did you do carb wise can you use the stock carb and put a bigger jet in it?

[@bigair0176]

I ran the stock jet. Put on a pod air filter. These bikes run rich from the factory. Most guys actually go to a smaller jet like a 65 main. I left mine stock.

[@kieren3933]

Thanks for making me over torque my head bolts its inch pounds not foot pounds 😢

[@jdsstegman]

Chamfer the ports!! And check squish band! Something that is never done on these "new" cylinders is they never chamfer the transfer ports or the exahust ports!! You must do this yourself. If there is no chamfer, the piston rings will wear out quicker as they scrape past a 90 degree corner.

[@bigair0176]

Thanks for the tip! Cheers

[@murph2521]

Is the bike still running? Great video by the way im doing the same to my sons pw an watching your series

[@bigair0176]

Yup it ran like a top. I ended up selling it as the kids were just not interested in riding a ton. So hopefully they will when they get a little older. With the big bore it was first kick every time. Ran strong and pushed me on it and I weigh 200lbs lol. Even up hills.

[@murph2521]

@@bigair0176 sweet and that stinks about them not being interested, I have 2 ten year olds and there not interested either but also have a 4yr old and a 5month old so the 4 yr old just learned to ride it without training wheels and dumped it a few times and the last time it wouldn't start back up. I went thru everything for 3 days straight trying to figure it out and ended up finding a pretty large stone or piece of steel looking thing in the intake sitting on the reed valve holding it open so I flipped the reeds,put it back together and she runs like a top now but man for 3 days I was starting to second guess my mechanical abilities lol I had already rebuilt the top end on it when I bought it and it didn't have 5 hours on it so thanks for replying,and your videos are definitely informative and helpful thanks

[@bigair0176]

Awesome. Glad you found the problem. I enjoy putting these vids up to help others. Glad they have helped you. Cheers!

[@roosterboy13]

What plug number are you running? Is it the stock plug or a hotter one?

[@bigair0176]

Well I am truly sorry I can’t answer your question. We sold the bike so I can’t go check the number for you. I just installed the plug that came with the kit.

[@roosterboy13]

@@bigair0176 no worries, thanks anyways 🤙🏼

[@wesleygain7778]

how long did it take?

[@bigair0176]

If you didn’t have to film any of it should only take a few hours from start to finish

[@dan79w]

Dude I hope you mean 88 in/lb no way will a pw50 head bolt go 88 ft lb. 7.0 ft lb would pull it up

[@jondoe7901]

I noticed that too. I had to replay it twice. Lol. Just got done doing a top end rebuild on one of my Yamaha lc50g Champ's. Same motor as the PW 50. ✌️

[@azgrandpadon6186]

The correct torque is 84-88 in/lb.

[@demimurgatroyd7705]

How does it run now

[@bigair0176]

The thing is a little beast. I kept the stock jetting just put a pod unifilter on it to help lean it out a bit. The boy has ridden it for about 1.5h hours so far. It pushes me now. It fires up first kick. Wish I had done this a while back but been putting it off cause I’m still waiting on the exhaust. I will do the exhaust vid soon I hope and I will talk more about what this 60kit did. It will spin the tires when the boys gooses it now. Lots of pep! Cheers

[@upaiaq]

Anyone know where to get aftermarket plastic for the 50 and 90?

[@ToolManTaylor]

Wow that old piston was trash. He will be pulling wheelie in no time.

[@bigair0176]

What a difference that bike has now. It tugs me along at 200lbs no problem. Even up some hills. It spins the wheels from a stand still. Can’t wait for the exhaust.

[@bbullsj]

I'm looking for some help from more knowledgeable people on 2 strokes. I got a 97 pw50 2 stroke and I can get it to idle but not have an throttle response. Pretty much all of the parts are new and I've checked everything I can. Any ideas? Here is a link of what it is doing. kzbin.info/www/bejne/n4bbXmqfpZpgZ80 It has a 60cc big bore kit, new wiring harness, exhaust, carb, spark plug, stator, kill switch, coil, air filter element, fuel filter. It has good compression, it's getting gas, no exhaust restriction (it's off in the video), I've tested the switch and I get good readings when I should and OL on my meter when I should. I'm totally stumped although there can't be anything left to try that I can think of.

[@bigair0176]

I have a vid that describes how to set and adjust your throttle /carb/ pilot screw and your idle screw on my channel. That may help you

[@kieren3933]

Soooo pissed

[@megamindtvsydney3967]

Wow why so much carbon? Better to mix fuel and oil

[@bigair0176]

Bike runs rich stock.