The manufacturer states that you should use 16:1 for break-in and 20:1 after. 32:1 will cause your cylinder to wear quickly. Different oil ratios are more dependent on ring thickness. If you noticed the rings on these bike are very thick. Two stroke dirt bikes have thinner rings and require less oil. I have a YD 100 and it's about to make a year that I've ridden to work six days a week. My compression is just as good as new. I built a YD 100 for my buddy and he has believer in less oil. He runs a 32:1 ratio and his compression has decreased by 7 psi in only three months. He was complaining about lost power and I didn't find anything wrong with the motor so I went buy a compression gauge. The results are clear and prove that a 32:1 ratio will cause premature loss of compression.

, thank you for your support for the motorized bicycle community.Youve helped me greatly in getting started.stay safe and keep it under a 100mph

Excellent Alex. Got my YD100 on Monday. My next project. As always good tips.

Great video as always!

Love the yd100 I just milled the jug by hand to receive the dio reed aluminum plate came out ok runs strong af n it’s not tuned yet been working on a dif daily bike but it really moves. Thanks for video.

Very true comment..."Expansion Chamber" is the #1 best mod you can do to increase the performance of any 2 stroke engine!

Been waiting for this! Thanks!

Dope video FX too.

I got mine this summer,did a rough break in but it worked for what I wanted.my crank seals have a small air leak.it comes and goes,I can’t get my drive gear off for the life of me so I have been putting berring grease arround the seals and rod and it works until the gas rats through.great bike!I have for upgrades is an bbr ignition and coil/cdi.an my 65 pipe,for now until I get my header for kx 65 pipe!but other than that I have a 32 tooth sprocket on the rear and I can get to 40.needs jetting,seals header and clutch pads.but starts every day,warms quick w my ngk-b7hs.higher rpms runs smoother.

Cool vid. Great Sauce!! (Shirt) Thanks for the tips.

I have a stock on goes 30 26 up hill have 1056 miles on it just broke it in with 20 to 1 now I run 40 to 1 and about every 100 miles I do a tank with 30 to 1

I've been dealing with two strokes my entire life and I'm a pretty old man now. All two strokes need to be properly broke in I don't know what happened on KZfaq to the videos and the kids and the people posting weird different ways to do it. when you start your two-stroke for the first time you don't give it more than 1/4 throttle RPMs piston movement up and down in the cylinder and rings all seat during the first quarter tank of gas. after you run a full tank at no more than 1/4 throttle you run your second tank at no more than half throttle third tank at no more than 3/4 throttle and I know this is four tanks of gas to break a motor in but when you're done and everything is seated properly your motor will be 100% different than if you jumped on your bike after you assembled it and took off down the road. It's a series of heating and cooling heating and cooling and heating and cooling figure that out. All this stuff where you see people running motors in front of fans(zero loads on the bike no loads on the clutch etc just sitting still at idle,,,, wrong) and doing weird things we've never done that and we grew up on two-stroke dirt bikes three wheelers and four wheelers the proper way to break them in is 1/4 throttle half throttle 3/4 throttle full throttle that's it never been any different until KZfaq.PS back then corporate was nowhere near as money hungry pushing crappy parts for your business at least we had quality Japanese parts to start with unless you guys the consumer sets the markets on the products that you buy this will continue to grow out of control and get worse until your children have garbage cans with wheels on them be careful what you buy and who you support and if you want my honest opinion how all this all really started is build it yourself stop buying stuff and make something from nothing that's how this really goes down.just remember what you're screaming spend that extra hundred dollars for this or spend that extra $100 for that corporate didn't spend that extra $100 to make it better they just took your money that's why I said build it yourself it'll be built better to your qualifications to your happiness at a fraction of the cost out of scrap parts. America

Rode my YD100 yesterday. She ran well but lost about 6mph. I revisted your vid on YD100 and decided to check the wrist pins........ One was missing and it damaged the inside of the jug 😱 I should have changed those clips 100 miles ago Thanks for the tips Bro

I hit 40mph easy on mine with 36 tooth sprocket. Ditch the wrist pin clips out of the box! Wiseco cw10 clips, The crank bearings in these leak like hell after 300 miles. Get some good brand name ceramic bearings to replace stock ones. get that thing ported to 20mm intake and exhaust and it screams!

That's a good YD 100 you have there. I can offer an advice to everyone is, never order this particular motor from a website called southern customs, very poor customer service and the motor it's self I've had nothing but heartache trying to get this motor broke in. Runs extremely rich right out of the box, double head gasket plus exhaust gasket and exhaust end doesn't mate correctly so gasket sealer is a must

AJ MOTORSPORT recommended me to check you out and to fallow you man am glad I did you do know what your talking about just like aj Motorsport ma respect to you man nice on the video and the info thanks 🙏🏻

Nice to see you back! Love your videos very detailed

I run a good 40:1 premix no ethanol 94 octane and I usually put some booster in it. Mines a no name and I got lucky with the break in. I bought an expansion chamber but it didn't fit my frame , a cdh power 3.4 liter , so right now I got a viper exhaust on it. With an hpc I got off Ali express with a hella air filter. I'm worried she's dying out though. But she does treat me good. What I will say is that for a no name she started right up out the box .and I've put Alot of miles on her fairly quickly. I like the yd100 I must admit I see a phantom 85 in my future

Yeah I just posted a good tip and trick you wanted me to post some. Milling the bottom of the jug, Where It Bolts to the block, shaving the base of that jug, or the deck, raises compression. period. Also, if you can find a piston with a different pin height, that would effectively raise the Piston height, this would also raise compression, although I do not recommend this way oh, it's a lot of work to clearance the piston. Another quick and dirty way to raise compression, especially on old bikes. Any bikes with the Dual spark plug cylinder heads: if you find any way to either Mill the top of the head, or do some machine work, to lower the spark plug cap deeper into the head, once clearance has been established oh, this is a guaranteed super easy way to raise compression on any two spark plug head, be it an old head or a new one.

like what u do.u help people that don't know about these motors..I would recommend 415 chain for everyone..my first two builds I broke a chain .but now I have never had a problem chain wise.only issue has been internal.bottom line for the price they r worth it

2 months so far...same yd100 firestorm..4l tank...fat belly pipe..21mm pwk carb, and 32 tooth sprocket on a trek 26in. Does 44mph.

Thanks for the video! I purchased bicycle 49cc engine only and I was thinking put on bicycle but it didn't came any thing!

I have 4 of these engine and they all run great gettin ready to ride it know like a 4 stroke but won't overheat the engine

Thanks 👍 again for another great video. I like the YD ....But I purchased the BT 100. Awesome engine and has plenty of power for me.but the thing is I want a different Exhaust.so I'm hoping Kause Kustoms can Help me... I have the stock Exhaust with the copper compression deal...so wish me luck.thanks Again for your videos.✌️💯

Great vid as always. I wanna know more about that sexy red cranbrook and the forks. Where can I get forks like that for my Nel lusso? Thank you

Good tip with the wrist pin clips I already did that from treatland.

Thanks for the review,and links.Have you tried a steel sleeved cylinder for the 66cc yet?I bought,and oiled 1 about a year ago.$37.I haven't tried the cylinder yet,and wonder what you think.I checked for 'flashing'but there was none.I'll chamfer the edges to all the ports as usual before use.(Duh,right?)

Got mine broke in and its a beast

Hey Alex. Did you happen to measure the stroke? I measured my YD100 and was surprised to find it was 38mm not 40mm. Checked to make sure I wasn't measuring incorrectly but mine is def 38mm. Anyone else seen this on a YD?

Very nice infos. thank you. if we have the regular 66-80cc motors, we have to replace the cylinder wrist pins too?

My yd 100 runs great will actually pull with a 32 tooth sprocket have yet to hit top speed mostly due to snow and ice but overall a nice motor with a few mods done to porting

I like your decal on that motor that's nice

nice video

I don't see the links in the description? I'd like to upgrade the wrist pin clips. Also there was no wrist pin bearing in my phantom 85 is this the same? Is there a bearing that can be added? Thank you for the video.

Hey as you got to the cons you mentioned the engine revving real high when the clutch is pulled. Air leak? Where should I start? I have an anbull 80 that's brand new the someone gave me as a back up but I'd much rather keep pushing my yd. I'm a bigger dude

Thanks for videos gizza, can I put my 80cc carburetor on my new yd100cc engine

I have saw dyno videos that only Reed valves, without widowed pistons, make the motor to loose much power. Have you make any tests about this?

just bought one, painted red! ehheheheheh

Green video bro I have that same motor and your right they have a lot better power great motor

Yes I have a yd100 I had a question since you build a lot of these bikes I really want to go a lot faster which engine or combination would you suggest for me to be able to go a lot faster

The way to raise the compression on the cylinders that bolt on the bottom: simply shave the bottom of the cylinder, where It bolts to the block. The more you shave from the bottom of the cylinder, the more it lowers the overall cylinder height, bringing the head closer to the piston, in raising compression through the roof. So those of you that say you can't do a high compression head or anything like that, guess again. 😎👍💯

Every yd100 will chew its stock piston pin clips in first 500 miles. First thing you do is pull them and replace them with cw10 wiseco clips. Piston pin has a bad bevel that will chew its clips grab pin off. Secondly fyi the bearings in the lower half leak air with a reeds installed. You have to change them in the case of a Reed added. Last thing yd100 has issues with on most. Stock intake almost never has an o ring inside card side and you get vacuum leaks out of the box. Motor is great if you fix those same crap parts each time

Great video! Audio is good, video quality is good, and the review was honest. Love it :) Question, do you have a link to where we can find those forks on your Cranbrook? I would like to grab a set.

Hey Alex just seeing how you were doing today I know it's mother's Day so I'm sure it's pretty hard you have a great day be safe tell your family I said hi happy mother's Day to your mom for you

I needed to split my case to look for metal as my piston broke at pin. I can't find gaskett to mach the case. Do you have idea where i can get them. The standard china doll gasket is differenf.

Is there much difference between the YD and the LD? The first thing I see the ld is a 2 piece jug/head. I just received the LD and dont want to blow it up. But The ports are very clean, which was a surprise.

I am ready to purchase a kit for my Mongoose and need to decide on going 2 or 4 stroke engines. What would you recommend?

Hi I had a yd 100 that I ported myself that I put on a 24”mountain bike with a banana pipe+a 60 jet for the carb and I had the problem of it reving out of gear so I just turned the idle down so it would die but I think I had that problem with the crank seals mine developed a bad knock so I decommissioned it but I hit 45+mph with a 36t back sprocket and it did lots of wheelies.

Hey bud have you ever ordered from blakoon before. Are they reliable. I have emailed them a couple times asking a few ?s and never received anything back. Would like to order their malossi 10mm wrist pins and a windowed piston. Just dont know how fast or reliable they are?

No I'm down I had knee surgery for the second time on the same knee on the 13th so it's going to be a while from back up and riding

SUBSCRIBED

I can use that YD 100 crank for a PK 80 is the same 40 mm stroke Long conecting rod

Hey to start off I'm a big fan u do amazing work on bikes and taught me a lot about them. Second I bought a yd100 and like I learned from ur videos it had a backwards piston so I changed it around. The big issue I'm having is somethings wrong with my lower half. I installed the motor to my existing kit and skidded to a stop when I tried to engage the motor. The sprocket doesn't budge and I was wondering if u knew what it could b with ur pro opinion

Where is good place to buy a good 100cc engine kit prebuilt and ready to go.. I purchased YD100 from Southern Customs engine ran like crap sputtered and carb would not fit correctly... What advise on a good 100cc engine kit prebuilt???

Question? How is the BT100 engine holding out?

Rdm clutch works well on my phantom v3 and my yd100 from gomax

I have a question I have 3 yd100 1 sounds like a dirt bike the other 2 have a little taping noise real light another builder said it was a exhaust echo anyway my question is they all came with 2 gaskets even the last 1 I Bought witch was a raw racer 3 it was already put together opened it up to put a window piston in to go with the Reed valve it had to gaskets does it need both?

I ran mine for about one minute full throttle do you think you’ll still be fine

Hey bro. Appreciate all the videos. I have a quick question that maybe you can help me with. I have a new kit and this is my first build.. I got everything set up and I go to test the spark plug, and no spark, so I took apart the magneto to check everything out. Made sure I had the magnet aligned properly with the woodruff key, everything is in order, and still no spark. I tested the cdi and the wires from the magneto. All good. Can you possibly help me out with what else I could possibly do? Edit: I'm sure it's something so simple.

What are the jet sizes? On a stock YD 100.

i jus got a zeda 100 love it but i think i scorched my top end realy wish i saw this vid first... mine did 40 out of the box.... but i wish i hadnt pushed it. it will start but will only barely run with me assisting it(by peddling) dies instantly when clutch lever is applied. I dont kno what to do, or replace... HELP?!?!?!

can you guys recommend me a decent throttle upgrade?

The ones that come with the 12mm wrist pin clips are the ones on Ebay that are not advertised as yd100 there advertised as a 100cc kit. Ive got two yd100 and one from Ebay is totally different. Has bigger wrist pin clips and different exhaust port shape.

Hey Alex what do you run your engines at for the oil mixture I got two phantom 85s the first one blew up they're sending me my second one and they're telling me to break it in at 25 to 1 for the first break in. And then they're telling me 20 to 1 after??? never mind question answered

Idk if you still have a million chain guards, but if you do you should make a logo for Motored Life with them

are the crank seals standard size? bt-100 is 30mm and I couldn't find replacements :/

oh I'd LOVE to hear about an upgraded tank! Is it stupid expensive though?

What motor would you recommend the most?

I toyed with the idea of putting a "hat" on the spark plug to raise compression but that's just bad, because an insert can come off, trashing the cyl. you can't even shave the jug without altering port timing. there _is_ a way to bolt a new combustion chamber or make a domed piston, but this isn't a mod for most MB hobbyists. I made a head for a China Girl before but modding this engine is a whole 'nother level. if these do well, I think we'll see 51 or 52mm pistons and jugs for these for the speed freaks haha

Alex be careful with the main seal with the magneto side mine went bad there for some reason the sales are going bad on in them

16:05 the motor stand flat to pipe we're can I buy one and what the cost

Hi I cannot get a straight answer from the folks who answer the phone (customer suppt) for the phantom 85,they send 2 head gaskets,when installing the jug I only used one ,are 2 necessary to avoid engine damage

Been hospitalized for two and a half days

Should I go with one of these or with a zeda 80 with a dio reed and oko carb

Im not getting the speed i used to when i first got engine. Its only 2 months old and it sputters when Im at full throttle. Do i have to change jets? Any advice woud be greatly appreciated

Can you explain or do a video on the yd100 crank play ? I feel like mine has to much its noisy

What main jet does it have

"Don't go over half-throttle for a couple gallons", that's pretty aggressive for break-in. A couple gallons at an estimated 90 mpg, means nothing above half-throttle for 180 miles? Break-in happens in the first couple miles, and the rings needs to be cycled though the rpm range.

Hey I have that kind of motor and the guy I bought it from told me it was broken in a I ran 32:1 in it for two gallons of 91 octane and after the first two tanks I started running it harder and something happened to it and don't know what because it won't run faster than 27 mph .

Hey Alex they're supposed to come with oz magneto in them mine did

Will you do a 4 stroke vid?

what did you mean by backwards magnets?

Outstanding man. Bike shortage.

40 tooth sprockets are the best imo

The break in for my engine was half a tank of feathering the gas and a couple of extra drops of the cheapest oil, running great atm. They are poor quality parts, im not spending the money for a new piston on some fancy oil...

okay so I burned through the bearings in my back wheel again. Why does this keep happening my bike does 38 miles an hour and I do ride it daily. Can anyone suggest either a good wheel or bearings. I haven't had breaks for well over a month but I am crazy like that LOL.Does this happen to anyone else or just me?

Just got a YD 100 but the piston rod is stamped zmn100… anyone know why???

Where are these links you are talking about

There is a motorized bicycles under the mary baker .

Kx85 works well to same with mikuni vm18

Eu tenho muita vontade de ter um motor desse, mas não tenho condição financeira.

You want it to fly put a chainsaw plug in it.ive been over 70 with chainsaw plug, barely runs thirty with stock plug.plug us shorter but really makes it go.

Can I send you my motor to open it up and to see if anything's wrong with it it's brand new

same shit they charge more .what u r doing is great to show people

Bro i know this comment is late but i been tryna find a engine size dimension for yd100 online but to no avail. I tried to look up seller specifications but they dont tell exact or close thereabout of engine size of yd100 length breadth and height. Can u pls tell me bro and in centimetres if possible. Thx

Do u sell the engine's

before everythings yet out of the box, Ill bet whoever put, "stuffed case" in the ad or description for this didnt even know what a stuffed case is. Its easy to lie about balanced crank cuz very few people will actually check or even notice the difference.

I believe only the super rat runs 6203 bearings

Is there a way to contact u for tuning help I have autism

wow 32-1 for breakin? amazon motors callin for 16-1 break in and 20-1 or 32-1 normal. whats the deal?