Post by mjordan2186 on Jul 4, 2024 8:45:39 GMT -5
Hello everyone. My name is Mike and I'm from Florida. I need some help with this scooter I'm working on. It's a 2021 wolf rx50. 4 stroke 50cc with the 139qmb. I got it from a guy who let it sit for 6 mos to a year after it wouldn't start. Long story short, the gas went bad. The tank got rusty as did the throttle cable. I drained and replaced the tank, thoroughly cleaned the carb, replaced the throttle cable, spark plug, and cleaned the air filter.
After I finally got it running, it would stall and I learned it had low compression of 60-75psi.
So I replaced the piston and cylinder head too. Compression now reads the same as my other scooter at 100psi on my Amazon compression tester. The scooter starts and idles great. And for reference, my other scooter starts and runs like a beast with only 100psi reading. My guess is that the compression tester reading may come in a little lower than actual due to displacement size or quality of tester. Moving forward, both scooters test at 100psi and my "other" one flys, tops out at 45ish.
My rebuilt Wolf starts and idles great but has low power and tops out at 30. It has a small power band up until 15 but is just much lower power up until it tops out at 30.
The carb is good. It has been interchanged and runs great on my other scooter.
The top end is brand new and fires right up and idles good.
There is a distinct noise that I hear, it is hard to explain, while driving the weak wolf.
It sounds like a soft whirring sound. Not high pitched, but just a hum of sorts. Variator and clutch seem fine. But the noise sounds like it's coming from the crankcase. It sounds like it's a gentle whirring noise coming from behind the variator.
My question is this:
Can the crankshaft/bearings cause a low output of power to the CVT? The top end and it's timing all seem to be working as they should but the power that should be getting to the wheel isn't getting there.
The scooter doesn't get to excessive rpms when riding it. It has 6g sliders and a stock clutch. When I start it pulls away pretty close to normal with a small power increase up to about 15-20, then it about half as slow as it should be getting to 30 where it tops out. The only thing I hear that stands out is a humming/whirring sound that's coming from the crankcase area. Very much the bottom of it or right behind the variator to be precise.
What can you guys think of that could be causing this low power?
My instincts are saying crankcase related, maybe bearings or something inside causing a lower transfer of power. But I haven't read many things that support how a crank/bearings can cause a low output of power.
Thanks in advance for any help. I'll keep you posted of any changes or findings.
After I finally got it running, it would stall and I learned it had low compression of 60-75psi.
So I replaced the piston and cylinder head too. Compression now reads the same as my other scooter at 100psi on my Amazon compression tester. The scooter starts and idles great. And for reference, my other scooter starts and runs like a beast with only 100psi reading. My guess is that the compression tester reading may come in a little lower than actual due to displacement size or quality of tester. Moving forward, both scooters test at 100psi and my "other" one flys, tops out at 45ish.
My rebuilt Wolf starts and idles great but has low power and tops out at 30. It has a small power band up until 15 but is just much lower power up until it tops out at 30.
The carb is good. It has been interchanged and runs great on my other scooter.
The top end is brand new and fires right up and idles good.
There is a distinct noise that I hear, it is hard to explain, while driving the weak wolf.
It sounds like a soft whirring sound. Not high pitched, but just a hum of sorts. Variator and clutch seem fine. But the noise sounds like it's coming from the crankcase. It sounds like it's a gentle whirring noise coming from behind the variator.
My question is this:
Can the crankshaft/bearings cause a low output of power to the CVT? The top end and it's timing all seem to be working as they should but the power that should be getting to the wheel isn't getting there.
The scooter doesn't get to excessive rpms when riding it. It has 6g sliders and a stock clutch. When I start it pulls away pretty close to normal with a small power increase up to about 15-20, then it about half as slow as it should be getting to 30 where it tops out. The only thing I hear that stands out is a humming/whirring sound that's coming from the crankcase area. Very much the bottom of it or right behind the variator to be precise.
What can you guys think of that could be causing this low power?
My instincts are saying crankcase related, maybe bearings or something inside causing a lower transfer of power. But I haven't read many things that support how a crank/bearings can cause a low output of power.
Thanks in advance for any help. I'll keep you posted of any changes or findings.