Best tranny for trail riding/hills/woods

[zackattack91]

Wondering what's better for hills and trail riding. Semi auto 125, auto 125, or CVT 150? Is the semi auto worth the it to change and drop gears if you can't get up a hill? Or will the auto 125 or 150 get an average 150 pound guy up a steep hill? Thanks in advance. Just don't wanna buy one without knowing the advantage and disadvantage of the different transmissions.
Also, which brand has better quality frame/welds and overall sturdiness? Taotao or coolster?

[JerryHawk250]

Originally Posted by zackattack91

Wondering what's better for hills and trail riding. Semi auto 125, auto 125, or CVT 150? Is the semi auto worth the it to change and drop gears if you can't get up a hill? Or will the auto 125 or 150 get an average 150 pound guy up a steep hill? Thanks in advance. Just don't wanna buy one without knowing the advantage and disadvantage of the different transmissions.
Also, which brand has better quality frame/welds and overall sturdiness? Taotao or coolster?

Hi Zack and welcome to the forum. I have the Coolster 150 with the CVT. I'm about 185 and have no problem hauling my big butt up hills and through mud. we took a trip a few weeks back where they had some pretty steep hills and my daughter stuck right with me on the trails but she only weighs about 100#. The Coolster has been a good reliable ATV. I've had it for 2 years and only changed the rear break pads.

[JerryHawk250]

Just to give you an idea what the Coolster is capable of here is a picture of one of the hills on the trail it went up. I wish I had a picture of the Coolster. A little scary but made it. Note: This picture was just to show the hill. We had made it to the top and I took a picture of someone who followed us up.
Attachment 7976

[zackattack91]

Nice man. So the 150s have the CVT auto. The 125s have just a regular auto? I've heard that the CVT belts are hard to maintain. How is the CVT different than the auto on the 125s?

Originally Posted by JerryHawk250

Just to give you an idea what the Coolster is capable of here is a picture of one of the hills on the trail it went up. I wish I had a picture of the Coolster. A little scary but made it.
Attachment 7976

[zackattack91]

Also, I've never seen an atv with a cage or a canopy. Or was that picture just to show the hill?

[JerryHawk250]

Originally Posted by zackattack91

Also, I've never seen an atv with a cage or a canopy. Or was that picture just to show the hill?

That was just to show the hill. We had made it to the top and I took a picture of someone who followed us up. It just goes to show you the you don't have to spend $15-20,000 to climb a hill. lol

[JerryHawk250]

Originally Posted by zackattack91

Nice man. So the 150s have the CVT auto. The 125s have just a regular auto? I've heard that the CVT belts are hard to maintain. How is the CVT different than the auto on the 125s?

I'm not sure how the 125's are set up. In two years I have not had any problems with the belt. Now I jinx myself and it will more than likely break now that I said that lol.

[Weldangrind]

The CVT on the 125 is an oil bath type, quite similar to the small Honda motors, like the XR50. Very good and reliable system, but I don't know how much mass they can overcome.


The CVT on a GY6 scooter-based motor is a dry belt, and it's very tunable. You can buy higher quality belts, better clutch material, stiffer springs, assorted roller weights, etc. You can tune it to launch hard and dig in or tune it to come on soft for a gentle ride. They are an excellent design.


I've told this story before, but I used my 150 GY6 quad to pull Jr. dragsters 1/2 mile back to the pits. The dragster had a teenager in it, and my son was riding two-up with me on the quad. I was about 215lbs at the time, and he was probably about 125lbs back then. That quad took a beating and never complained. I still have it, and I've never changed the belt or the CVT parts.

[zackattack91]

thanks for the explanation. so the 125 is still a cvt, but the motor and the tranny share the same oil. the 150 however does not, and has a separate area for transmission fluid? because by nephew has a taotao 125 auto F-N-R, but i didnt think it was a belt driven clutch. just though it was give it gas and go with mechanical gears. would you mind explaining the difference between the oil bath type and the dry belt driven 150? thanks.

Originally Posted by Weldangrind

The CVT on the 125 is an oil bath type, quite similar to the small Honda motors, like the XR50. Very good and reliable system, but I don't know how much mass they can overcome.


The CVT on a GY6 scooter-based motor is a dry belt, and it's very tunable. You can buy higher quality belts, better clutch material, stiffer springs, assorted roller weights, etc. You can tune it to launch hard and dig in or tune it to come on soft for a gentle ride. They are an excellent design.


I've told this story before, but I used my 150 GY6 quad to pull Jr. dragsters 1/2 mile back to the pits. The dragster had a teenager in it, and my son was riding two-up with me on the quad. I was about 215lbs at the time, and he was probably about 125lbs back then. That quad took a beating and never complained. I still have it, and I've never changed the belt or the CVT parts.

[Weldangrind]

Originally Posted by zackattack91

thanks for the explanation. so the 125 is still a cvt, but the motor and the tranny share the same oil. the 150 however does not, and has a separate area for transmission fluid? because by nephew has a taotao 125 auto F-N-R, but i didnt think it was a belt driven clutch. just though it was give it gas and go with mechanical gears. would you mind explaining the difference between the oil bath type and the dry belt driven 150? thanks.

The 125 is not a CVT, it is simply a centrifugal clutch; it is either engaged or it is not.

The video that was posted probably explains the dry CVT process better than I can. I'll relate that design to the 125 centrifugal clutch, to try and fill in the blanks.

Both systems use a centrifugal clutch; one is dry (the 150) and the other is bathed in oil (the 125). The dry system subsequently spins a belt that controls a continuously variable transmission (or CVT), whereas the wet system does not. In other words, the CVT acts like it has gears, because the ratio constantly changes with RPM, but the wet system acts like one gear only.

The torque converter on your go-kart is identical in concept to the 150 GY6 CVT, and the 125 wet centrifugal clutch is identical in concept to a simple centrifugal clutch that can also be used on a go-kart. The wet centrifugal clutch in a 125 is only bathed in oil for cooling and longevity.

The 125 centrifugal clutch setup shares oil between the clutch and crankshaft; the 150 CVT does not. In a 150, the crankshaft happily spins in oil that is not shared, so it does not need to be an oil that is suitable for a wet clutch. For this reason, I use 10W30 oil in my 150 GY6 CVT engine. The 125 centrifugal clutch should use oil that is wet-clutch compatible, like any 15W40 motorcycle oil. At the driven end of a 150 CVT, there is a set of gears within the housing, and they require gear oil; I use 75W90 synthetic oil for that.

[zackattack91]

Thanks for the info!

Originally Posted by Weldangrind

The 125 is not a CVT, it is simply a centrifugal clutch; it is either engaged or it is not.

The video that was posted probably explains the dry CVT process better than I can. I'll relate that design to the 125 centrifugal clutch, to try and fill in the blanks.

Both systems use a centrifugal clutch; one is dry (the 150) and the other is bathed in oil (the 125). The dry system subsequently spins a belt that controls a continuously variable transmission (or CVT), whereas the wet system does not. In other words, the CVT acts like it has gears, because the ratio constantly changes with RPM, but the wet system acts like one gear only.

The torque converter on your go-kart is identical in concept to the 150 GY6 CVT, and the 125 wet centrifugal clutch is identical in concept to a simple centrifugal clutch that can also be used on a go-kart. The wet centrifugal clutch in a 125 is only bathed in oil for cooling and longevity.

The 125 centrifugal clutch setup shares oil between the clutch and crankshaft; the 150 CVT does not. In a 150, the crankshaft happily spins in oil that is not shared, so it does not need to be an oil that is suitable for a wet clutch. For this reason, I use 10W30 oil in my 150 GY6 CVT engine. The 125 centrifugal clutch should use oil that is wet-clutch compatible, like any 15W40 motorcycle oil. At the driven end of a 150 CVT, there is a set of gears within the housing, and they require gear oil; I use 75W90 synthetic oil for that.

[mr.drey]

Originally Posted by Weldangrind

The 125 is not a CVT, it is simply a centrifugal clutch; it is either engaged or it is not.

The video that was posted probably explains the dry CVT process better than I can. I'll relate that design to the 125 centrifugal clutch, to try and fill in the blanks.

Both systems use a centrifugal clutch; one is dry (the 150) and the other is bathed in oil (the 125). The dry system subsequently spins a belt that controls a continuously variable transmission (or CVT), whereas the wet system does not. In other words, the CVT acts like it has gears, because the ratio constantly changes with RPM, but the wet system acts like one gear only.

The torque converter on your go-kart is identical in concept to the 150 GY6 CVT, and the 125 wet centrifugal clutch is identical in concept to a simple centrifugal clutch that can also be used on a go-kart. The wet centrifugal clutch in a 125 is only bathed in oil for cooling and longevity.

The 125 centrifugal clutch setup shares oil between the clutch and crankshaft; the 150 CVT does not. In a 150, the crankshaft happily spins in oil that is not shared, so it does not need to be an oil that is suitable for a wet clutch. For this reason, I use 10W30 oil in my 150 GY6 CVT engine. The 125 centrifugal clutch should use oil that is wet-clutch compatible, like any 15W40 motorcycle oil. At the driven end of a 150 CVT, there is a set of gears within the housing, and they require gear oil; I use 75W90 synthetic oil for that.

Weldangrind , thanks a lot!!!

This is so far the best explanation of the difference between 125 and 150 i could find. Appreciate it.

[Merlin]

I use CVT on some of my motorized bicycle builds and you ride up a telephone pole with mine.

[katoranger]

The 150 CVT in the buggy(much heavier) does well. I tuned it for low speed pulling power. In the winter we have had two adults in it with 2 adults or 3 kids on sleds or tubes behind it. That belt is abused. We did have one fail than damaged parts. I think we got it pretty hot.

Nice thing about the CVT. You can't be in the wrong gear.

[zackattack91]

Am I correct saying that the CVT can detect when you need more torque to get up a hill? Something maybe with the CDI?