Advice appreciated

[Kilroy]

Hi all, long time listener first time caller here. So my bike has a 4-stroke hua sheng 49cc engine with the centrifugal (automatic) clutch. Today I was riding and something happened with the clutch so that it changed to being permanently engaged. I would appreciate any advice as to a fix. I know i've read somewhere that these clutches have a tendency of arriving in the box with the clutch 'stuck' and I know there's a simple way to fix it.

My gut says the spring either broke or there's something (a piece of debris or a geartooth maybe) preventing the spring from retracting. But before I take it all apart I would love to hear from you guys, especially if you've had the same or a similar problem in the past.

Thanks a lot! If you have any questions about the specs of the engine that you think may be relevant please ask.

 

[2door]

Broken clutch spring or springs.
There are three of them that keep the clutch pads disengaged until centrifugal force pulls them out to engage the clutch.
Tom

 

[MotorBicycleRacing]

You don't say what gearbox you have on your Huasheng.
There are 2 different shaft types for the Huasheng motor.

Where did you buy your kit from and what company?

Pull it apart and let us know what you find.

 

[Kilroy]

Broken clutch spring or springs.
There are three of them that keep the clutch pads disengaged until centrifugal force pulls them out to engage the clutch.
Tom

Yeah, i definitely remember that from the diagram and from when i took it apart prior to installing it. Thanks for the imput - I think it may be the springs just by the noise it's making.

You don't say what gearbox you have on your Huasheng.
There are 2 different shaft types for the Huasheng motor.

Where did you buy your kit from and what company?

Pull it apart and let us know what you find.

I don't know what kind of gearbox or shaft i have, or how to look that up. I have a couple pics here, let's see if i can post them...

http://a7.sphotos.ak.fbcdn.net/hpho...205835213_100002564032961_81914_4925796_n.jpg

http://a3.sphotos.ak.fbcdn.net/hpho...405835193_100002564032961_81921_1051253_n.jpg

I got the engine and the kit from a seller on ebay, so i don't really know how to check what company it came from... I thought the company was huasheng? I know it's the kind of gearbox that you can't open up, unfortunately.

I know that i've seen replacement clutches for this engine all over the net (I took a look at it prior to installing partly to check that the clutch was working ok, so i have a vauge recollection of what it looks like). If I end up having to get a new clutch assembly I'll be kinda irked, but no big deal really. I'm hoping I can just replace the spring(s) if that's what's wrong with it.

Thanks for the imput guys! Let's keep it coming, I really appreciate it.

 

[KCvale]

Can you roll the bike around freely with the motor off?
If not the clutch is seized engaged and not very likey, but if you here it rattle then it's springs.
If not the springs may have just gotten a little weak and a drop or two of light oil in the cup and maybe a little lower idle speed may get you going again.

One last thing.. did it get wet and stay wet for a long time?

 

[wayne z]

Looks like you have the Hoot chainbox.
Why can't you open it up? It needs to be opened and lubed once or twice to make to about 300 miles if yer lucky.
They don't have a good track record. Mine crapped out at about 250 miles, the case wallowed out away from the bearings. Great lil motor though. There are better trannys out there that fit this motor.

 

[2door]

Don't be surprised if when you open up the clutch that a spring is missing. Actually there's no way the spring can get out of there but what can happen is when it breaks, the spring can get thrown through the elongated slots in the clutch bell and fall in behind it.
I just repaired one for a friend and found the spring between the bell and the case. I had to remove the clutch bell to get the old spring out. Good luck, let us know how you make out with this.
Tom

 

[Kilroy]

Hey thanks for all your replys fellas. So I did fix the clutch today - the problem was that one of the three springs had actually come unhooked from one of the feet and had lodged itself in such a way that one of the feet could not retract. So what had actually been going on is two of the three feet were working fine but one was stuck in the engaged position. I just dislodged it and reconnected it, after clearing away some of the gunk. Anyone attempting this at home would be well advised to grab some needle nose pliers for the job.

The end of the hook on the spring is chipped a little, so I don't know how permanent this fix is going to be (I'm looking into ordering a replacement now, if anyone has a recommendation on a good place to get replacement parts that would be awesome) but the bike works fine now so i'm satisfied. After taking a closer look at the clutch assembly I'm not surprised this happened, it definitely seems that the springs are the 'weak link in the chain' if you will. I might end up replacing all three with higher quality springs, but we'll see.

Thanks again for all the thoughtful replys! I really do appreciate it.

 

[Kilroy]

Looks like you have the Hoot chainbox.
Why can't you open it up? It needs to be opened and lubed once or twice to make to about 300 miles if yer lucky.
They don't have a good track record. Mine crapped out at about 250 miles, the case wallowed out away from the bearings. Great lil motor though. There are better trannys out there that fit this motor.

All I know about the gear box is that it has the letters 'XHD' embossed on the side and it uses a chain. What i mean by i can't open it up is that if i take off every bolt that I can turn, the front plate loosens but is still held by something on the inside on the small side. I think it may be possible to turn the only other bolt, but it's connected to the drive line and my attempts to turn it result in turning the gears and the drive sprocket. Since the sprocket has a freewheel mech inside I can't hold the sprocket to still the bolt, and I can't find any other way to get leverage. I don't really need to though, with all the other bolts off the plate's loose enough that i can pry it open a few millimeters on the other side and shoot some spray lube at it, which i do when i change the oil.

I would definitely be interested in getting a better gearbox for it, if you had any specific recommendations i would be glad to hear them. And yeah, i love that little motor!

 

[wayne z]

Hey Kilroy, There are bearings in there that are a light fricton fit tnto the cover. If you
pry on opposite sides of where the resistance is with even pressure, it will come off

Dax sells a better inespensive chainbox with a double row chain and a heavier case.

I've heard good things about the 4G tranny but I don't know how available they are.

The stock 44t sprocket is way too small. The clutch spent more time slipping than engaged. I changed to a 56t and still is geared a little too tall. I think a 60t sprocket would be better.

 

[wayne z]

I converted my Chainbox to oil bath, and it worjed great until the case wallowed out around the clutch bearing at 300 miles.

I made a gasket for the cover and tapped and added a drain plug low on the cover, another slightly higher for the fill level added a small vented filler cap made from lamp hardware atop the case, and used motor oil in there.

 

[Kilroy]

Hey Kilroy, There are bearings in there that are a light fricton fit tnto the cover. If you
pry on opposite sides of where the resistance is with even pressure, it will come off

Dax sells a better inespensive chainbox with a double row chain and a heavier case.

I've heard good things about the 4G tranny but I don't know how available they are.

The stock 44t sprocket is way too small. The clutch spent more time slipping than engaged. I changed to a 56t and still is geared a little too tall. I think a 60t sprocket would be better.

Ok cool! I thought that might be the case but i have a nasty habit of breaking things that i don't know how to take apart properly and i didn't want to take the chance. I'll definitely give that a try next time i look at the bike.

 

[locutus_1]

broken spring or springs get rid of those stock springs they are horrible get some 1/4 inch ones from a hardware store they are small enough to fit in and cut them to lenght of the old ones bend them the same way walla you have new springs for 3 bucks and they engage right after throttle..

ive had mine for a while they work great no more 75% throttle to take off

 

[Lance Portnoff]

glad to hear a success story on you fixing your clutch