I got my Dax 10 tooth drive sprocket on Fri. as well as my 56 tooth driven sprocket (not from Dax; Ebay item) so a weekend of tinkering ensued.
1st, the 10T didn't fit the shaft of the pocket bike CVT. It was slightly too small. That's a good thing! Actually, it is exactly the same size as the shaft which is why it wouldn't go on. A few minutes with a file and BINGO...perfect fit. If you do this, take it easy with the filing as the metal is really 2nd rate (not hardened) and files away quickly. Be careful!
I used a large nut drilled out to the shaft size (9/16") as a spacer/shim, to align the chain on the CVT shaft, which needed one link removed for the smaller dia. sprocket. Also, this sprocket is straight cut so I touched up the tips of the teeth with the file as I was getting some rub inside the chain.
I started off with the original 44T driven and was impressed with the crispness of the take-off. I could FEEL the MOMENT the clutch grabbed the bell and the bike actually JUMPED forward. NO, no wheelies, lol, but a definite PUSH off the line. I could feel it in the seat as the clutch engaged. Top speed came down only slightly, from high speed of 28MPH on flat to 26MPH. That was kind of expected. I did NOT notice ANY difference in RPM (Subaru/Robin 33.5) though from the 12/44 to the 10/44.
Next up was the 56T driven swap for the 44T. 1st problem there was the mounting (rag) holes were off and I had to re-drill 9 new ones to match my existing mount. I don't know if that is normal with these different size sprockets or not. Simple enough fix though. The rest of the mount was typical. I cut a new, longer hunk of #41 chain and was ready for a test run.
Immediately, I was getting a rythemic popping sound from the chain as the wheel went around. The chain was wanting to rise off the ring and then settle again! Strange. Turns out the teeth on the sprocket looked more like a saw blade with some teeth SET. A few were bent inward; others were bent outward. Sub-par quality here. As a minor note, the chrome was OK on one side and lacking and scratched to heck on the other. Definitely not a quality piece of work. Straightened the bent teeth with pliers which was almost too easy. All back together and time for the test ride; again.
Off the line was only marginally better than with the 44T. Still no wheelies. High speed fell to an unacceptable 20MPH. Still no RPM change but hill climbing was slightly (only very slightly) better than with the 44T although the 44 did very well in my opinion. On my local hills the bike climbs good and accelerates as it goes. Good in my book!
I was in hopes of getting the engine RPM to go up and therefore maybe a little bit better performance and less stress on the CVT, but it wasn't to be. I guess between the small 4 stroke, the tank it's mounted to, and my 200lb. self, ya can only do so much.
Overall, I was happiest with the 10/44 combo which kept my top speed and added low end AND climb so I put the 44 back on. I was really hoping to get a solid 30MPH going for those times when you need a little extra, but I never had it before so I won't miss it. I'm satisfied with what I've got and although I was not really too fond of the chain drive, it feels more solid and reliable now. I guess only time will tell. Still no wear on the CVT belt with about 200 miles so I guess the RPMs are agreeing with it.
I will probably order another 10T from Dax just to carry with me as a spare along with some extra shaft clips.
Hope this helps others looking into these pocket bike CVTs.
WC
1st, the 10T didn't fit the shaft of the pocket bike CVT. It was slightly too small. That's a good thing! Actually, it is exactly the same size as the shaft which is why it wouldn't go on. A few minutes with a file and BINGO...perfect fit. If you do this, take it easy with the filing as the metal is really 2nd rate (not hardened) and files away quickly. Be careful!
I used a large nut drilled out to the shaft size (9/16") as a spacer/shim, to align the chain on the CVT shaft, which needed one link removed for the smaller dia. sprocket. Also, this sprocket is straight cut so I touched up the tips of the teeth with the file as I was getting some rub inside the chain.
I started off with the original 44T driven and was impressed with the crispness of the take-off. I could FEEL the MOMENT the clutch grabbed the bell and the bike actually JUMPED forward. NO, no wheelies, lol, but a definite PUSH off the line. I could feel it in the seat as the clutch engaged. Top speed came down only slightly, from high speed of 28MPH on flat to 26MPH. That was kind of expected. I did NOT notice ANY difference in RPM (Subaru/Robin 33.5) though from the 12/44 to the 10/44.
Next up was the 56T driven swap for the 44T. 1st problem there was the mounting (rag) holes were off and I had to re-drill 9 new ones to match my existing mount. I don't know if that is normal with these different size sprockets or not. Simple enough fix though. The rest of the mount was typical. I cut a new, longer hunk of #41 chain and was ready for a test run.
Immediately, I was getting a rythemic popping sound from the chain as the wheel went around. The chain was wanting to rise off the ring and then settle again! Strange. Turns out the teeth on the sprocket looked more like a saw blade with some teeth SET. A few were bent inward; others were bent outward. Sub-par quality here. As a minor note, the chrome was OK on one side and lacking and scratched to heck on the other. Definitely not a quality piece of work. Straightened the bent teeth with pliers which was almost too easy. All back together and time for the test ride; again.
Off the line was only marginally better than with the 44T. Still no wheelies. High speed fell to an unacceptable 20MPH. Still no RPM change but hill climbing was slightly (only very slightly) better than with the 44T although the 44 did very well in my opinion. On my local hills the bike climbs good and accelerates as it goes. Good in my book!
I was in hopes of getting the engine RPM to go up and therefore maybe a little bit better performance and less stress on the CVT, but it wasn't to be. I guess between the small 4 stroke, the tank it's mounted to, and my 200lb. self, ya can only do so much.
Overall, I was happiest with the 10/44 combo which kept my top speed and added low end AND climb so I put the 44 back on. I was really hoping to get a solid 30MPH going for those times when you need a little extra, but I never had it before so I won't miss it. I'm satisfied with what I've got and although I was not really too fond of the chain drive, it feels more solid and reliable now. I guess only time will tell. Still no wear on the CVT belt with about 200 miles so I guess the RPMs are agreeing with it.
I will probably order another 10T from Dax just to carry with me as a spare along with some extra shaft clips.
Hope this helps others looking into these pocket bike CVTs.
WC
