How to install a big bore kit GY6 171cc / 172cc (61mm). EVERYTHING YOU NEED TO KNOW! 

I don’t even have a gy6 engine but still found it fascinating

25:25 setting valve lash. You go on the bottom side (.004 to .005 and you pick .004) . Only thing is that as valve and seat wear( in a hot combustion chamber) the oil splashed cam and rockers wear less. This almost always ends up in valves that don't seat completely, which is accelerated by valve erosion and ALWAYS pronounced on the exhaust valve due to coefficient of thermal expansion differences based on heat/cooling cycles. Exhaust valve is only cooled from oil and seated contact (heat transfer). Intake is cooled by both those but mainly by cold fuel intake (reason carbs "ice up" is evaporation) in relation to relevant heat within the combustion chamber. If in doubt, ALWAYS set valve lash loose. Especially on the exhaust. They Will wear in and close the gap, so to speak.

Spot on vid m8 deffo the best one I’ve seen and thanks for the info was just about to fit my m8s big bore 👍🏻

This is a really good tutorial because you have a clear and step by step tutorial, I subcribe! Hit the bell and thumbs up..thank you

Great video! I just bought a Hammerhead buggy with the 150cc GY6. Thanks for the info.

this is the perfect how to video for the GY6 motor I have just done this build with a 180cc motor 63mm piston looks just the same except over here in the UK on our scomadi version of the Gy6 out motor hanging mounts are underneath compared to your top version and we have a disk back brake

I love how straight forward this is. I think I'm going to be buying a lot more scooters so I can teach my kid and learn myself

I love love love the gy6 out of all the engines to tear down to every last bolt the gy6 comes apart so nice and goes back nice easy to work on bullet proof and many many mods I love rolling wrench

Thanks for this like big time. I can’t find anyone to do my work, so I must learn.

AWESOME TUTORIAL !!! From Philippines

Because of your fully explanation I subscribed thank you hope more video regarding rebuild of GY6 150 motors

As many others have already stated, great job! I just had to jump on the long list of others that appreciate your great content! Sub'd

Thank you. Our 150 is just tired of the abuse my son did on it, so instead of buying a new engine, I decided to rebuild with a big bore kit. This is the exactly the video I was looking for. I will add the performance cam, larger carb (28mm or 30mm) and i hope this thing will fly :-)

Just put a Mikuni carb in but popped the head gasket in the process when starting it up, ordering y’all drop in kit Friday I’m hyped

awesome build video dude. super informative and detailed mate.

Outstanding! Step by step.

awesome video man, thanks for putting this up.

Perfect video 👍

0.04 is to tight clearance for air cooled engine, u need to put 0.10,when its get to working temp, tht clearance is 0.05, and u nvr gonna burn your valves,just my opinion, cause i have 170 cc gy5,157qmj block and its going 115kph tht would be 71 miles per hour btw good tutorial

Have some experiene with motors but man , still learned someting new, great tutorial, thx!

That was the single greatest tutorial video I have ever seen. Can you do my gy6 atk 150c buggy tao tao? To slow

I've always wondered what the little rubber hoses hanging off the little modified 125cc scooters in Taiwan were: your breather tube just answered my curiosity!

Nice tutorial. Very helpful.

you have some great build videos though. tons of good information.

Great information,thanks

Great video

Like seriously, I'm a mazdaspeed 3 owner, lost my engine... wel actually my car was stolen not long ago, anyways, over the years of learning about my engine, seeing this video I swear is like perfect for people who want to know a how their engines work and get an idea what pistons are like and how to work them as well as well long story short this videos good for anyone interested in their engines! Extremely versatile video just instead of 1 piston just add your piston count and rinse and repeat the process and just like the rings, 1 is 1 way the next one is opposite and so on and so forth, it's like a seesaw one up one down

Excellent clear and concise instruction, well done, i can tackle my gy6 top end rebuild with much more confidence, thankyou.

Just purchased the 171big bore just and two valve performance head, also throwing in the A9 cam can't wait to see my scoot fly

Thanks for the great video, lots of detail and well explain. I'm replacing the cylinder head on an old Lance Venice inherited from a friend and discover the old piston lost some fragments into the crank case. Any suggestions on how to clean this out or make sure there is nothing left inside that may create a problem ? Also I have no specs regarding nuts torque. what would you advice. Thanks!

Well done. Subbed

Desde colombia te mando un abrazo aunque no entiendo tu idioma entendí el tutorial a la perfección muy bien explicado te felicito Muy bueno

Nice to work with new engines

Great Video thx

very clean 🤩

Very good Informations :-) i install a 160ccm on my Kymco super 8 GY6... greets from germany...

Great vid mate you explain everything thing in detail. It looks like you don't need to re jet the carb is that right?

Very good video men...

Friend, I congratulate you, good video you explain everything very well, few videos of such good quality you can find and your video is the best I've seen in terms of mechanics, I have a buggy with 150 cc engine. By making this modification do you know how many hp I can increase? And finally, if I make this modification, will I have to change something in the carburetor? and you recommend some spark plug coil with more voltage? There will be a high voltage coil on the market for this 150 cc engine.? Thank you very much and again I congratulate you for your video, in fact you explain very well and the quality in hd is very well appreciated all the details. Greetings.

I am a Taiwanese. I just installed a 61mm cylinder on my 26year old 125cc GY6 scooter. It becomes young again！

That's a great video. Thanks a lot. I learned to many things and feel appreciated.

You made a boring tool for a drill!?!? That's so cool

Need this guy in the uk 🇬🇧

U r very accurated!

Very nice

do you have a vid showing how to split and change out the crank

Hai, you are very expert about scooter especially, i need a tips from you, i have a modenas elit 150 scooter, how to make it powerful than nw?... What do i need to change to?

Thanks 🙏🙏🙏 brother....

you should make some videos about 200cc or 250cc or 300cc mopeds/scooters

I just got a 4 seat go-kart for my kids that need motor/electrical work it has a gy6/clone I'm going to build it now

The oil breather u have look like it have a dipstick with it too do you seek that whole thing exactly like the one on the video ??

Love your videos, new to the scooter world. Considering purchasing a maddog trike because I'm a big guy. Have you had any experience with this bike. Thanks in advance.

Swip it! Great how to. 👍

Is there a way to get more power out of the stock ruckus without adding a gy6. I know a lot of people like the stretched look but I prefer the stock length of the rear.

Hello. great and detailed video. Can you please leave the link to buy the long gy6 engine with the 171cc kit and carburetor already installed, that is, ready and tested to mount on my scooter, just make the connections and start?

Buen video amigo

Also on the piston should I order cast or forged? Thank you for all info

You make it look very simple. Im saving up for a second bike, it will be a gy6 scooter. In the meantime i wanted to ask, would your EFI plug and play kit work on a geared bike? It has a 26mm intake is a 125cc... but what i am worried about is: will the EFI handle the constant changes in the throttle or is it made specially for scooters where you dont play that much with the throttle?

Where did you buy that oil dip stick thing, with the air thingy.

A piece of string/wire on the timing chain helps enormously.

Hi there, I’m installing this kit in my gy6 soon. Do you recommend the gasket sealant sprays? Thanks

19:00 to 19:11 true. But the reason is because the case is cut out. So he is saying if the alignment pins don't push in, they are in the wrong holes. Gasket is diagonally cut also for them. It only fits one way.

Thanks for putting up some great diy videos 👍 how can you tell if you have an A or a B case without opening it?

thanks for sharing., my question the same guage 004 intake ang ex or going to muffler?

Where did you get the crankcase breather/dipstick combo you don’t sell them just breathers

Hey with my cam lobes facing down. @22:07. My rocker arms HAS A LOT IF PLAY ROOM. SO I FLIPPED THEM. because I couldn't adjust the dowls on the valve. I have bug bore kit. With a-9. Cam. If I try to adjust the valve there's still like 1-1/2mm of play.

It looks the same as a XR/CRF80 or 100 in head and timing chain guide design, I have been cautious of working on OHC engines and now I have completed a few, they are easy.

I have to thank you for the excellent video. I have a 150 GY6 large frame scooter sitting in my shed awaiting a rebuild and this looks like what it needs. Now I wonder if you might have the parts necessary since my nephew got into the shed and strewed parts everywhere. I mean items like nuts and bolts that I will need for the project. He also managed to break off the mirrors too. He is no longer welcome at my abode. I will need quite a bit. Do you also have a manual covering the Chinese scooters? Thanks in advance.

Is there anything you have to do to the fuel system or to the carburetor to adjust for more fuel for this change in displacement

Did you check the ring end gap?

Hello my friend ✌ I should get a good power hike with the 171 big bore using my stock head , because the motor has less then 100 miles/ what due you recommend on carb in mm & what # cam, looking for a decent gain with dependability & pricing . Appreciate the info thank you

Perfect

Does all a cases fit the 61mm bbk without boring the case? I have a 125cc gy6 stock and planning on upgrading it to the biggest bore possible without touching the case. Most say 58.5 is the limit without boring the case. So if this kit is bolt on i will surely go with this.

sir its that okay to use stock camshaft without camshaft stopper plate?

Do y'all make performance parts big bore kits for the cn250 roketa mc250

Awesome

Hello i have an aprilia rx50 (2017 ) (distrangulated) and an honda crf450rx but im Racing enduro ON my 50cc , how can i give more power to my 50cc

Is it good performance just by changing the cylinder? Isn't it necessary to change the carb too?

Can you use 125cc Gy6 cylinder head on 180cc Gy6 cylinder? Whats the intake and out take diameters? - But you just mentioned smaller cylinder head adds to compression = power output. But how about those intake and out take holes? How much they matters for power output when using the default 125 cc carburator?

hi rollingwrench, I would like to ask if all 157QMJ engines (China), will fit the 61 mm big bore kit without modifying or boring the hole for cylinder wall? thanks.

I usually set the piston inside of the cylinder first as a lil assembly then install the dowel and clip that way I don't have to wrestle with the piston rings.

I plan to convert from 125cc to this. Do I need bigger exhaust? And what about carb? Bigger jets?

Hi I have a BN152QMI engine what's the max I can go without milling the case ? I might look to buy the tool as I have 2 of these thanks

Hi, i juz have a quick question. Does this setting can be implemented into Scomadi TT125i model? Since my scooter r using ECU (injection).

Im wanting to do this to my GY6

I recently bought a 2020 150cc ice bear q6 trike, don't know nothing about this Brand n I cant find no reviews about it. Are they any good? Are they able to keep up hours of stop n go n Long drive as well? Can I upgrade modified it? What issues do I need to look out for, what to I need to replace if anything. Any info will b great plus I'm a 300 lbs dude any help will work plus I'm new to this world of scooters.

Hello sir, I’m installing the Taida brand 61 mm big bore kit like yours and an A12 camshaft. I’m thinking of upgrading to a CVK 30mm carburetor and intake but the intake port on the head is 28mm wide. Is that ok or should I go with a 28mm carburetor? What do you recommend? Thanks

Anyone know where I can find a replacement shroud gasket/seal? I cant find one for the life of me.. any help is appreciated. Love this channel

Can i apply this to my baotian classic? it has a gy6 engine and is from 2007 or 2009. Does this kit then work?

if I replace my air filter with a power air filter where should I place the crankcase ventilation? Its for an yamaha zuma

I have a big bore 171 Dongfang. Would swapping the stock out for this make any difference? Thanks!

would there be a change with the carb or jettings using 61mm block? I heard you can run stock 150cc carb upto 59mm block only. beyond that, jettings should be changed.

So you can use a 150cc head on a 171cc cylinder?? Reason I ask if because I've stripped out my spark plug hole and I'm trying to helicoil it now but I would much rather replace head in the end.

just a hypothetical question: can the new head be installed with the engined mounted to the bike "in situ"? Or must you remove the entire engine to be successful?

Quick question.. I have the 157qmj motor on my buggy...what is the difference from the same motor on a scooter? Cause the item description says If installing on a buggy or sxs they don't guarantee fitment. just curious.

my question to u is which big bore did install that u didnt have to bore the case ? what brand ?

It would be nice to know the before and after HP ratings torque also would be great...

Great video! Question: what size carb do you run on this engine? and also what jet size? Thanks!

Sir, isn't the scale regarding valve settings supposed to be in ’parts of an inch’ rather than mm? Big fan, love your videos!

Does the breather tube breathe or is it just a chamber to relieve pressure