Noise from engine at 50 mph

[~Cheap_Ride~]

Recently I have noticed some vibration and noise from my PCX that usually starts at 48 mph and lasts thru 52 mph. The bike doesnt seem to be affected by this as performance is good all the way from start to top end speed. I need to get it up to the dealer before warranty expires (july 3 2014) I just havent had time to do so.

Has anyone else experienced something similar to this? Did you figure out what it is or where it comes from if you have?

[kramnala58]

How many miles (kms?) have you got on it?

[~Cheap_Ride~]

1004 miles

[kramnala58]

1004 miles

With that few miles, I would take it to the dealer as it shouldn't be a regular maintenance issue. Hopefully it is a consistent problem and not intermittent because if the dealer can't hear/feel it when you take it in then he is likely not going to do anything about it.

[~Cheap_Ride~]

I talked to the service manager last night before the dealership closed. He wants me to do a few things on my own to see if there is any effect on the noise/vibration. One is tire pressures. He did say though that I need to bring it in before the warranty expires. The problem occured again this morning going up the long hill on my way to work, and like magic at 53 it quit. It is short in durration, perhaps 20 seconds and always between 45 and 55 mph. The bike ran just fine and I dont feel any loss of performance what so ever. I think it may be fan related, IE: fan bearing on its way out.

It will be another week before I get the opportunity to get it out to the dealer.

[apeacezalt]

Mine got some vibration between 25 - 40 mph , but it not too much , I usually ride at 50-60 mph, so that's ok :-/

[A1ex]

hey guys, did u figure it out where the vibration comes from? I tried almost all the 110 cc bikes here in Thailand and they all have this weird kind of vibration which is rising up as you speed the bike up. Usualy starts at 40 km/h when u can physicaly feel it and the frequence is rising till after 60 - 70 km/h it becomes almost unnoticeble. the only bike that didnt have it (it was barely noticeble) was a pretty new honda click 110cc.

[you you]

I talked to the service manager last night before the dealership closed. He wants me to do a few things on my own to see if there is any effect on the noise/vibration. One is tire pressures. He did say though that I need to bring it in before the warranty expires. The problem occured again this morning going up the long hill on my way to work, and like magic at 53 it quit. It is short in durration, perhaps 20 seconds and always between 45 and 55 mph. The bike ran just fine and I dont feel any loss of performance what so ever. I think it may be fan related, IE: fan bearing on its way out.

It will be another week before I get the opportunity to get it out to the dealer.

Does the fan have a bearing. In my mind it was effectively bolted to the crank

[A1ex]

ok, so after talking with a few experienced folks i kinda came to a conclusion that this is most probably tires out of balance. I wanna try using ceramic beads (so far only found dyna bead on the internet, not sure if there are other brands) as an alternative way of balancing the tire since it is difficult to find a workshop that has neccessary equipment on the island. Has anyone ever used those beads?

[maddiedog]

I used Dynabeads on my Nighthawk with much success, it didn't make a difference on the PCX though.

The fan definitely has a bearing, even if it's bolted to the crank, but if it was going it would have more effects than just a noise.

Generally on the PCX, some slight shuddering at certain RPM ranges occurs due to the belt slipping on the variator. My PCX did it with the stock variator, and an aftermarket one. I get slight shuddering from somewhere around 15-25mph for about 2 or 3 seconds during acceleration. The noise doesn't come on suddenly, it fades in then fades out.

[you you]

I used Dynabeads on my Nighthawk with much success, it didn't make a difference on the PCX though.

The fan definitely has a bearing, even if it's bolted to the crank, but if it was going it would have more effects than just a noise.

Generally on the PCX, some slight shuddering at certain RPM ranges occurs due to the belt slipping on the variator. My PCX did it with the stock variator, and an aftermarket one. I get slight shuddering from somewhere around 15-25mph for about 2 or 3 seconds during acceleration. The noise doesn't come on suddenly, it fades in then fades out.

Where is the bearing if it's bolted to the crank? Between the fan and another bearing surface?

Not saying you are wrong, just saying I don't understand

[A1ex]

Generally on the PCX, some slight shuddering at certain RPM ranges occurs due to the belt slipping on the variator. My PCX did it with the stock variator, and an aftermarket one. I get slight shuddering from somewhere around 15-25mph for about 2 or 3 seconds during acceleration. The noise doesn't come on suddenly, it fades in then fades out.

Yeah man, i think that is exactly what it is, at least it make some kind of sense to me now. i tried all the scooters here in Thailand and they all have this kind of shuddering at the speed exactly between 40 and 60 km/h, it fades out as soon as you get above 60 km/h. It cant be that all of them are having out of balanced wheels. As for the dyna beads, i dont know but i think it made the bike smoother on high speeds up to 80-90 km/h. but i has only put one ounce to the rear wheel so far may be its just my imagination. Thank you for your answer, realy appreciate it.