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

BUY THIS 171cc KIT:

BUY OUR COMPLETE 61MM BIG BORE KIT:

BORE TOOL:

ENGINE WORK STAND:

Valve lash .004-.005

If you are a newby and have no idea how to install a big bore kit on your GY6. No problem. this " how to install a big bore kit" video will walk you through the entire thing. No special tools needed! If you find this video helpful and want to support us please join our patrion page!

[freestyleskyline]

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

[stevebiggs]

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

[oldwortex]

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 :-)

[synoptic]

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

[yewwtooob]

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.

[lienchen]

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

[s]

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

[youtubeuniversity]

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

[basmu]

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

[FreakinKatGaming]

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

[brodjohn]

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

[seishiro]

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

[ipaddy]

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

[alex]

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.

[ab_customz_llc]

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

[MrJoeyoung]

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

[joolsfreeman]

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

[stuartcairns]

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 👍🏻

[MarjanSpasevski]

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

[jacobdenham]

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