[Robbo13]

Hi Jason, I am from Oz and have a 150 for my boy. I am trying to get the hold of a 12 tooth sprocket but there are so many types, is it 17mm or 20mm ID? it to suit a 420 or 428 chain?
Forgive me if these seem dumb, I am a dirty old mechanical fitter but I am not near the buggy at the moment and cant get a measurement to check for myself.
I am also keen to know what success you had with the dynojet kit, was it easy to fit up? What were the results?
Thanks in advance!
Rob

 

[Ghost CMC]

Little update on my build…. Added the music, sound bar, underglow, light bar, switch panel and painted the dash. Might add a slim subwoofer next for a little added bump and maybe a windshield and doors. My daughter is about to be 15 so it might be time to sell this one and start looking for a 570 or similar. This thing is just way to cool. It’s super capable on the trails and the kid loves the sound bar. Just might be a little small at this point. Whenever we have a party, I pull this out of the garage and run the battery tender out to it and play music all night. Better than any little Bluetooth speaker!

 

[Beefking69]

Hello all,

I would like to discuss performance upgrades for a Polaris ranger 150 EFI 2021 model. I bought the new Ranger for my kids and noticed that the ground clearance was not as advertised. I love all the new features and think it’s perfect for my kids. I recently purchased a new set of rear tires that are 14 inch rims with 26 inch tires. I have a lift kit ordered that I plan on only using the on the front end to kind of level the UTV a bit And leave stock 22 in factory tires on the front.(2 in) This has significantly increased the ground clearance in the rear by about 2 inches. (Was around 6.5 now 8.5)

I took it out with the kids on about a 30 mile ride and had no issues with him hitting anything. I did however notice that the larger tires had trouble in sand and would like now to increase the performance of the machine. After doing some searching I found a few performance clutch parts that I plan on installing. Namely a performance torque driver and clutch. I’m also getting some smaller rollers.

now I’ve been looking at big bore kit’s and crankshaft and wondering if anybody has any experience.

I can tell through research that this UTV has the GY6 motor with serial number jl1p57f. It is an a model that I verified by measuring the bolts on the cylinder head.

with the a model GY6 the largest I can safely go is the 63 inch big bore kit. Then I will have to bore out the case. I can also get a +3.5 mm stroker crank shaft that will put me at a 191 cc engine.

has anyone done any of these mods on the Polaris ranger 150? I’m specifically wondering if the electronica fuel injection is enough fuel for this size and if boring the case makes it too weak.

my kids are too small for the 570 and I really want to make this machine work until they’re old enough.

thanks for any of the comments.

These are A-block internal reverse gy6's. You can use 61mm (170cc) drop in cylinder kits. 62mm (175cc) 63mm(180cc) kits will not fit without boring the block. The only 3 drop in 61mm kits are made by Taida/Ssp-g/Ncy.

There are no stroker cranks available for the internal reverse gy6s as the internal reverse cranckshaft has two different size crank bearings and the stroker cranks have the same size bearing on both sides. Plus the variator side of the internal reverse cranks are different from the stroker cranks. Stroker cranks can be made to work if you know what your doin and how to do it.

Little update on my build…. Added the music, sound bar, underglow, light bar, switch panel and painted the dash. Might add a slim subwoofer next for a little added bump and maybe a windshield and doors. My daughter is about to be 15 so it might be time to sell this one and start looking for a 570 or similar. This thing is just way to cool. It’s super capable on the trails and the kid loves the sound bar. Just might be a little small at this point. Whenever we have a party, I pull this out of the garage and run the battery tender out to it and play music all night. Better than any little Bluetooth speaker!

Looks good and theres plenty of other goodies for these 150cc machines.

The fuel injection is calibrated for the diameter of the throttle body, not the size of the engine - changes to the intake and exhaust will affect the fuel injection, but it will have to be hooked up to a dyno and re-calibrated by an experienced tuner with a program compatible to the electronics.

Boring the engine will give a bit more low end grunt and revamping the variator will change the engagement characteristic, but you will need to get a high lift cam to get back some of the top end you lose when you increase the bore. Likewise the stroker crank will boost the low end grunt wile lowering the redline RPM limit.

Have fun - engine building is great if you have the time and money - if you have the time, you might get it all done in a 2 to 4 week to month time frame. If you are going for maximum performance allow about 6 months to a year for disassembly, machining, clearance checking, head porting, recutting the valve seats for the larger valves, checking the clearance between the piston and the valves and the overlap clearance between the intake and exhaust valve (one is opening as the other is closing and they have to miss), finding an over sized exhaust system to match the enlarged exhaust port, final assembly and the dyno runs to fine tune the EFI.

Now get the variator tuned for the performance curve of the engine, possibly consider a heavy duty driven clutch assembly and a heavy duty belt.

Whew! I think I would just consider a Chinese 250 instead of all the work of building a Chinese 150 into a 160+, but on the other hand, if you have free time, go for it and let us know how it progresses

There is no machine work involved in building a nice 170cc gy6. Step one.....Buy performance parts.....Step two.....Install said performance parts....Step 3.....Enjoy. Performance parts are cheap for these and they are easy and simple to build. It doesnt take days or weeks or months to build a nice performance gy6. I persnally can build a 150 to a 170 in 30 minutes or so from the ground up. The performance heads already come with bigger valves and stronger springs. There is no need to check clearances on these kits as everything is designed to work together out the box. You do not lose top end by goin to a big bore kit......You will gain both lowend and topend......Theres nothing to check on the cams either as you simply install/reset timing and go. There are no off the shelf stroker crank for this particular gy6 (internal reverse) but even the bored and stroked gy6s are still capable of running the same 9-10k rpms as the non stroked gy6s. Ive personally got gy6s running 11k rpms on stock cranks. Cvt upgrades are a must on any gy6 powered machine....Stock or built. A built gy6 machine can smoke a standard china 250cc machine but i do like my 250cc buggys.

I await the simple cliff note version. I too have bought a ranger 150 for my kids and am not happy with the power to ground performance. Spent enough on it new. Hate to spend much more on this thing.

Taida 61mm cylinder kit.....Taida/naraku/ssp-g/ncy 58.5mm big valve head.....A14 camshaft......banjing clutch/clutch bell.....yellow springs (clutch and big spring).....banjing 115mm variator.....12g sliders (not rollers)......Uni filter air filter.....some kinda aftermarket exhaust.....and then have it tuned.

Can you please let me know the exact part numbers of everything you ordered. sprockets tries clutches. Everything please!!!!!!! I keep ordering the wrong stuff

See above.

@Jason k I think this is the sprocket we are looking for Amazon.com: Polaris RZR Sprocket-Drive, Genuine OEM Part 0454563, Qty 1 : Automotive
I ordered it and will try to get it installed this weekend.

Also I found this on another forum, dude said it worked perfectly on his 2018 Ranger 150 - Amazon.com: Factory Spec, FS-1709, 12 Tooth Front Sprocket fits Polaris 2009-2019 RZR 170 : Automotive

Hammerhead 150cc 12t sprocket also as this is the same motor on the hammerhead buggys.

Hi Jason, I am from Oz and have a 150 for my boy. I am trying to get the hold of a 12 tooth sprocket but there are so many types, is it 17mm or 20mm ID? it to suit a 420 or 428 chain?
Forgive me if these seem dumb, I am a dirty old mechanical fitter but I am not near the buggy at the moment and cant get a measurement to check for myself.
I am also keen to know what success you had with the dynojet kit, was it easy to fit up? What were the results?
Thanks in advance!
Rob

See above. 530 o-ring chain/sprockets.





Join "Gy6 Buggy and kart performance" and "Gy6 go kart dune buggy performance" on FB as theres tons of good info on these gy6 based machines.

 

[Bestranger]

thanks a ton. Do you really need it tuned after swapping the hard parts. I have no idea who could do that????

 

[Beefking69]

thanks a ton. Do you really need it tuned after swapping the hard parts. I have no idea who could do that????

You only need a tune if you change cylinder/head/cam/intake/exhaust. If you just do the cvt upgrades then you dont need a new tune. Any reputable atv shop that works on bigger rzrs/can-ams etc should be able to make a decent tune but they would need a dyno so they could dyno tune it. Edit....The stock efi will be able to compensate for mods to a point but itll never be just right without a good tune.