New Rider
Currently Offline
Posts: 15 
Likes: 1
Joined: Apr 17, 2015 17:56:32 GMT -5
|
Post by madirishman on Apr 17, 2015 18:10:06 GMT -5
50cc taotao scooter with new carb, pin at center position, and 89 jet. All else stock. Valves - in .003/out .005. A month ago, the belt blew at top speed (doing about 40) replaced belt, and top speed dropped to 32. Started mixing rollers and I guess I went one to many times, but I stripped the threads on the drive shaft. I replaced the drive shaft, put in new gaskets, reassembled the engine and went on a test drive. Was doing ok, and suddenly rattled, lost power and died. It started back up but did the same thing at about 25mph (7000 rpm). New plug, same results. Valves, variator/clutch/belt, and fuel lines are all ok. What else can be causing this? Also no oil leaking.
|
|
|
|
Post by geh3333 on Apr 17, 2015 18:19:08 GMT -5
Where is the rattle coming from ?
|
|
New Rider
Currently Offline
Posts: 15
Likes: 1
Joined: Apr 17, 2015 17:56:32 GMT -5
|
Post by madirishman on Apr 17, 2015 18:29:32 GMT -5
Where is the rattle coming from ? Not sure. It goes from 25mph to dead in just a couple of seconds. |
|
|
|
Post by geh3333 on Apr 17, 2015 21:43:11 GMT -5
Can you hear the rattle at idle ?
|
|
New Rider
Currently Offline
Posts: 15
Likes: 1
Joined: Apr 17, 2015 17:56:32 GMT -5
|
Post by madirishman on Apr 17, 2015 23:10:47 GMT -5
No. On the center stand, I can rev up over 10k with no problem. Only with a load over 25mph (7000 rpm)
|
|
|
|
Post by geh3333 on Apr 18, 2015 3:26:05 GMT -5
I wonder , since you say you have a new carb , if when you get up to that speed at 7000 rpms if your carb is running dry , hesitating causing something loose to rattle . does it take a few times of turning the engine over to start again ? And does the scoot hesitate at all while shutting down.
|
|
|
|
Post by lain on Apr 18, 2015 4:24:00 GMT -5
This sounds really similar to a problem a friend of mine had where he would stall out seemingly randomly while driving. Shortly before he would stall out you could hear clacking/clicking coming from the carb. Turned out his petcock wasn't working right anymore. My theory is the clicking/clacking is the sound of the needle slide moving when not dampened by fuel.
|
|
New Rider
Currently Offline
Posts: 15
Likes: 1
Joined: Apr 17, 2015 17:56:32 GMT -5
|
Post by madirishman on Apr 18, 2015 5:27:11 GMT -5
I wonder , since you say you have a new carb , if when you get up to that speed at 7000 rpms if your carb is running dry , hesitating causing something loose to rattle . does it take a few times of turning the engine over to start again ? And does the scoot hesitate at all while shutting down. Yes, I have to turn full throttle and kick (I shorted out the ignition module while soldering on the tach) a few times to restart. Not sure about the hesitation, it pretty much just dies. |
|
New Rider
Currently Offline
Posts: 15
Likes: 1
Joined: Apr 17, 2015 17:56:32 GMT -5
|
Post by madirishman on Apr 18, 2015 5:30:59 GMT -5
This sounds really similar to a problem a friend of mine had where he would stall out seemingly randomly while driving. Shortly before he would stall out you could hear clacking/clicking coming from the carb. Turned out his petcock wasn't working right anymore. My theory is the clicking/clacking is the sound of the needle slide moving when not dampened by fuel. I'll change out the petcock and try it again. |
|
|
|
Post by geh3333 on Apr 18, 2015 6:27:56 GMT -5
I wonder , since you say you have a new carb , if when you get up to that speed at 7000 rpms if your carb is running dry , hesitating causing something loose to rattle . does it take a few times of turning the engine over to start again ? And does the scoot hesitate at all while shutting down. Yes, I have to turn full throttle and kick (I shorted out the ignition module while soldering on the tach) a few times to restart. Not sure about the hesitation, it pretty much just dies. You may need to adjust the float in the carb bowl. I think you may just be running out of fuel . as for the rattle , I'm not to sure without hearing it. |
|
New Rider
Currently Offline
Posts: 15
Likes: 1
Joined: Apr 17, 2015 17:56:32 GMT -5
|
Post by madirishman on Apr 18, 2015 14:10:06 GMT -5
Update: changed the petcock, still died. Changed fuel filter. Still died. Removed air filter, didn't die, but top speed of only 18mph. Then loud scary noise from trans box. Variator bolt had worked loose. I'm letting it cool off now and will post more soon.
|
|
New Rider
Currently Offline
Posts: 15
Likes: 1
Joined: Apr 17, 2015 17:56:32 GMT -5
|
Post by madirishman on Apr 18, 2015 16:42:17 GMT -5
Scary noise was crank shaft and drive face shredding each other. Crank shaft has groove cut into teeth and inside teeth of face are gone. Going to order new crank shaft, drive face and get the 80cc upgrade while I'm at it. All new innards should fix the problem, right?  ?   |
|
|
|
Post by geh3333 on Apr 18, 2015 16:49:09 GMT -5
Scary noise was crank shaft and drive face shredding each other. Crank shaft has groove cut into teeth and inside teeth of face are gone. Going to order new crank shaft, drive face and get the 80cc upgrade while I'm at it. All new innards should fix the problem, right? ? How did that happen ? |
|
New Rider
Currently Offline
Posts: 15
Likes: 1
Joined: Apr 17, 2015 17:56:32 GMT -5
|
Post by madirishman on Apr 18, 2015 17:11:43 GMT -5
No idea. Was doing a test run, heard loud grating sound, stopped scooter and when I pulled cvt cover off, that's what I found.
|
|
|
|
Post by urbanmadness on Apr 18, 2015 18:46:00 GMT -5
I can tell you what happened...... most likey...
One of two things......
One, the belt wasn't down in the clutch far enough when you put the drive face back on, so when you tightened the variator nut, it snugged up against the belt and not the dowel meaning the variator wasn't tight. It might of felt tight, but it wasn't.
Two,
One of the weights flipped in the variator when the belt broke, or when you were putting it back together. Net results, same thing. The variator nut wasn't tight. Might of felt tight, but it wasn't.
Two is probably what happened in your case. Only because you described a rattle. That is a symptom of an out of position weight. Not to mention the lack of top speed, and general misbehaving of the scooter.
|
|
