Taotao atm50 isnt happy

silofox · 08-01-2019, 10:31 PM

Hello all! long time lurker/reader but this is my first post.

For the past few days, my 2011 taotao 63 has been near impossible to start. If I do choose to turn it over for a couple minutes, it'll eventually start to putter but has very little power. Ill top out at MAYBE 25 on flat and hills that I can usually go 30 on will slow me down to 5-10. I weigh ~145lbs and usually have 20lbs of tools and junk with me. It will also stall unpredictably, requiring another couple minutes of cranking to restart. I have tried two different carbs, both cleaned before use. New fuel lines, Valves set to a TIGHT .006 (my smallest feeler).. has been fine for ~1500km. New spark plug, gapped @ .024, spark checked against valve cover, Compression tested @ 145psi and holds. Mechanical timing is correct from everything I can see ("T" mark, marks on sprocket, rocker nubs positioned correctly). Spark plugs indicate i'm running rich, which i'm ok with having heard these tend to run lean and burn up rings. I dislike starting fluid but have tried it to no effect. Vacuum lines are still stock (i think) but all connected and in good shape. Bike has ~2400km on it, 2000 of which I've put on it since getting it a few months ago. Up until now its run very well, usually starting up with one or two kicks, even @ 30F.. I also checked the oil from my last two changes and it was metal free. Im sure I'm leaving something out but ill add it if I remember

Heres a video of it cranking.. when it give it some gas, ill get a faint popping sound and it definitely produces some exhaust

and a compression test

It seems to me like the spark is out of time.. Im reasonably competent when it comes to the mechanical side of small engines but electricity is still boarderline magic to me. Open to any ideas.. this thing is basically my car at the moment.

Thanks,

James

tortoise · 08-01-2019, 11:48 PM

Quote:

Originally Posted by silofox

It seems to me like the spark is out of time.

Any chance the crankshaft-flywheel woodruff key was sheared . . which would throw off the pickup-coil ignition timing a bit?

Insert a probe into sparkplug hole to determine when the piston is at top-dead-center . . then observe if the flywheel T-mark is aligned with the case indicator.

Advance video to 7:46 . . .

benhonda · 08-01-2019, 11:58 PM

I've had a bad CDI box do some weird stuff before...like produce a spark when check with a spark tester but still not allow the bike to run (spark was either weak or timed wrong) and I checked a bunch of other stuff before plugging in a spare CDI box and the bike started right up.
Things like the CDI box, ignition coil and pulse pickup can go suddenly on these bikes. If you ride one often, it's good to keep spares. On the upside, they are cheap. A CDI box and ignition coil together are only about $20 on amazon.
Since you have ruled out fuel, and you have compression, and testing spark against the head can give a false positive...I'd replace first the CDI, then the coil...and if that doesnt fix then the pulse pickup.

culcune · 08-02-2019, 12:03 AM

Are you a member of http://49ccscoot.proboards.com/ ? Lots of scooter specific knowledge there, and they are Chinese scooter friendly.

silofox · 08-02-2019, 12:10 AM

Thanks, I'll take a look at that tomorrow. Vehicle is stuck at work as I didn't trust it for my 10 mile ride home. The lines on the gear that he mentioned are the ones I was referring to though. They're flush with the case when I have the T lined up.

Im also gonna go to my local scooter shop tomorrow morning and see what they have to say.. they wouldn't even talk about potential problems until I had done a compression test. They don't work on china bikes but they carry parts and the main mechanic there is pretty cool, very knowledgable and helpful.

Any chance it could be a bad cdi? Before things got bad, it would usually start with a kick or two when cold but was a little more difficult once it warmed up. Never really figured out why but it wasn't a big problem.. by more difficult, I mean 4-8 kicks or a second or two of electric start.

silofox · 08-02-2019, 12:21 AM

Quote:

Originally Posted by culcune

Are you a member of http://49ccscoot.proboards.com/ ? Lots of scooter specific knowledge there, and they are Chinese scooter friendly.

not yet but I was probably gonna post on another forum or two.. Thanks for the suggestion. I've had small bikes for 15 years but this is the first problem I haven't been able to work out with friend or google search

Ive done a lot of searching over the past few days and problems that sound similar to mine usually turn out to be something simple like a stuck vacuum petcock, which mine doesn't even have or go unresolved. Didn't wanna post anywhere until i'd ruled out everything I could.

benhonda · 08-02-2019, 12:25 AM

Quote:

Originally Posted by silofox

Thanks, I'll take a look at that tomorrow. Vehicle is stuck at work as I didn't trust it for my 10 mile ride home. The lines on the gear that he mentioned are the ones I was referring to though. They're flush with the case when I have the T lined up.

Im also gonna go to my local scooter shop tomorrow morning and see what they have to say.. they wouldn't even talk about potential problems until I had done a compression test. They don't work on china bikes but they carry parts and the main mechanic there is pretty cool, very knowledgable and helpful.

Any chance it could be a bad cdi? Before things got bad, it would usually start with a kick or two when cold but was a little more difficult once it warmed up. Never really figured out why but it wasn't a big problem.. by more difficult, I mean 4-8 kicks or a second or two of electric start.

If she has good compression...and you can spray starting fluid into the carb (or through the vacuum line at the intake runner) and it won't fire up for a second or 2, then the issue is spark...either not enough, or at the wrong time. A bad CDI box, ignition coil or pulse pickup could cause this. my money is on the CDI box. I've had one show a spark but still not start the bike. Plugged in a spare CDI, bike fired up and ran good.

silofox · 08-02-2019, 12:26 AM

Quote:

Originally Posted by benhonda

I've had a bad CDI box do some weird stuff before...like produce a spark when check with a spark tester but still not allow the bike to run (spark was either weak or timed wrong) and I checked a bunch of other stuff before plugging in a spare CDI box and the bike started right up.
Things like the CDI box, ignition coil and pulse pickup can go suddenly on these bikes. If you ride one often, it's good to keep spares. On the upside, they are cheap. A CDI box and ignition coil together are only about $20 on amazon.
Since you have ruled out fuel, and you have compression, and testing spark against the head can give a false positive...I'd replace first the CDI, then the coil...and if that doesnt fix then the pulse pickup.

Thanks! CDI is my main thought at this point. Can probably get one locally tomorrow. Like I said, this POS is my car ATM so the brick and mortar premium is quickly outweighed by the lyft rides it'll save. I definitely have a strong spark and I know i'm not losing it to compression because it WILL start if i crank it for an unreasonable period of time.. The low power also indicates to me that it isn't firing when it should, as well as the "popping" when I crank it.. I also know there is SOME combustion occuring as the exhaust warms up a little with a few seconds of this, along with some exhaust production. I'm just glad it wasn't compression. Was a little worried about it before today.

benhonda · 08-02-2019, 12:39 AM

Quote:

Originally Posted by silofox

Thanks! CDI is my main thought at this point. Can probably get one locally tomorrow. Like I said, this POS is my car ATM so the brick and mortar premium is quickly outweighed by the lyft rides it'll save. I definitely have a strong spark and I know i'm not losing it to compression because it WILL start if i crank it for an unreasonable period of time.. The low power also indicates to me that it isn't firing when it should. I'm just glad it wasn't compression. Was a little worried about it before today.

I buy and fix up 50cc bikes fairly often. 70% of the time the reason the bike was sold was because it sat for a time and then the carb got gummed up. The rest of the time there was an electrical issue that stopped the bike from running...the CDI box is the most frequent part that fails.

Once you get it running, it will be worth $20-$30 to buy spare CDI/ignition coil off amazon and keep them with you. Hopefully the brick&mortar store wont charge too much for a CDI.

dirtbkr188 · 08-02-2019, 07:55 AM

I'm not familiar with that style engine, but is there relatively easy access to the valve tappets for a possible valve clearance check?

silofox · 08-02-2019, 05:10 PM

Quote:

Originally Posted by dirtbkr188

I'm not familiar with that style engine, but is there relatively easy access to the valve tappets for a possible valve clearance check?

valves are in spec.. lol i've probably checked em a dozen times over the past week. they're very accessible on the gy6. Pop off the cover and they're right there. loosen a nut and have at em. none of the obnoxious little shim disk BS like my ruckus had.

silofox · 08-02-2019, 05:22 PM

went to the shop this morning.. Didn't get to talk to the mechanic that I usually do but the guy I did speak to didn't think it was the CDI. He sold me a new coil which didn't change anything and said CDI would be next.. Ended up having to shut down early at work today and managed to ride the thing home. I don't think I made it above 25mph on flat but fortunately only had to go up one hill, again I slowed down to 5-10. It's also very sluggish accelerating from lights and signs. Knowing its tendency to stall, I stayed on the throttle the whole time and just kind of forced it to a stop when I had to. Finally let off it when I got home and as expected, she cut out after a few seconds. Being warm does not cause it to start easier, same ridiculous cranking marathon as if it had sat for a day.

On the plus side, My speedometer started working again after hitting some bumps lol.. I have a new cable but haven't gotten to it yet as this BS started the same day I got it.

Guess I'm gonna take a walk back to the shop in a few minutes..

Also, YES, the piston is at TDC when it should be

EDIT: got new CDI, Problem fixed! the shop still didn't think it was my problem but it's not like they were going to refuse to sell me one.. Ended up paying $32 for both the coil and box. Not terrible for getting them without a wait, and along with some advice.

silofox · 08-06-2019, 11:21 PM

another update for anyone who cares or might read this in the future..

The CDI fixed the hard start problem but the thing still ran like garbage, still giving me the same awful power and acceleration. I revisited the keihin carb that came with the thing, gave it a real good cleaning, installed and saw a little improvement. I then moved my focus to the airbox.. for as long as I can remember, there had been a piece missing (cracked off)where the intake hose connected to it. I could literally cover the box intake and feel zero suction.. guess it was worse than I thought. I rigged up a ghetto filter to that replaced the box. It took a little trial and error but I got it running ok. I could still tell it wasn't getting enough fuel and the "filter" i made didn't really do much filtering. Needing a proper filter anyway, I went back to the scooter shop but they didn't have a stock airbox to sell me so I ended up with a pod, my only option there. I also picked up a couple jets (was using a 78 main, bought an 80 and 82. Anyway, the guy messed up and actually gave me an 82 and a 90. Id already regretted not going larger so this was a happy discovery. I got everything together, also upped the pilot jet to 34 from 28. Started her up and WOW! this thing runs better than ever and sounds awesome. easily hits 40 on flats now and has no trouble keeping up with the city traffic I usually ride in. I cant tell if the plug shows me running a proper mix or if it's a little lean so i might try going up to a ~95. 90 already feels high as I live in denver @ 5300ft but I cant argue with results.. Its also been in the mid 90s pretty much every day for the past few weeks so that might have some effect on things as well.

ride safe,
James

culcune · 08-07-2019, 01:19 PM

Glad to read you solved your issues! That seems to be the thing with Chinese made scooters; you have to work on them, and be willing to work on them. They are fairly reliable; at least the engine is, but once sorted out, will give you miles of riding pleasure.

benhonda · 08-07-2019, 06:33 PM

Quote:

Originally Posted by silofox

another update for anyone who cares or might read this in the future..

The CDI fixed the hard start problem but the thing still ran like garbage, still giving me the same awful power and acceleration. I revisited the keihin carb that came with the thing, gave it a real good cleaning, installed and saw a little improvement. I then moved my focus to the airbox.. for as long as I can remember, there had been a piece missing (cracked off)where the intake hose connected to it. I could literally cover the box intake and feel zero suction.. guess it was worse than I thought. I rigged up a ghetto filter to that replaced the box. It took a little trial and error but I got it running ok. I could still tell it wasn't getting enough fuel and the "filter" i made didn't really do much filtering. Needing a proper filter anyway, I went back to the scooter shop but they didn't have a stock airbox to sell me so I ended up with a pod, my only option there. I also picked up a couple jets (was using a 78 main, bought an 80 and 82. Anyway, the guy messed up and actually gave me an 82 and a 90. Id already regretted not going larger so this was a happy discovery. I got everything together, also upped the pilot jet to 34 from 28. Started her up and WOW! this thing runs better than ever and sounds awesome. easily hits 40 on flats now and has no trouble keeping up with the city traffic I usually ride in. I cant tell if the plug shows me running a proper mix or if it's a little lean so i might try going up to a ~95. 90 already feels high as I live in denver @ 5300ft but I cant argue with results.. Its also been in the mid 90s pretty much every day for the past few weeks so that might have some effect on things as well.

ride safe,
James

Wish I'd known about the cracked airbox hose. These small engines need the airbox restriction, otherwise they pull way to much air through the carb causing it to run lean, especially above 1/3-1/2 throttle. As you saw, going to a pod filter (which only has a little restriction) required much larger jets installed. I had to run a 105 main jet in a 50cc bike with a pod filter (sea level) I think stock most are running a 72-74 main jet. The funny thing is, even with a pod filter and larger jets the engine still doesn't make much more power than it does with stock carb/airbox setup. It will sound better though.

08-01-2019, 10:31 PM	#1
silofox Join Date: Aug 2019 Posts: 9	Taotao atm50 isnt happy Hello all! long time lurker/reader but this is my first post. For the past few days, my 2011 taotao 63 has been near impossible to start. If I do choose to turn it over for a couple minutes, it'll eventually start to putter but has very little power. Ill top out at MAYBE 25 on flat and hills that I can usually go 30 on will slow me down to 5-10. I weigh ~145lbs and usually have 20lbs of tools and junk with me. It will also stall unpredictably, requiring another couple minutes of cranking to restart. I have tried two different carbs, both cleaned before use. New fuel lines, Valves set to a TIGHT .006 (my smallest feeler).. has been fine for ~1500km. New spark plug, gapped @ .024, spark checked against valve cover, Compression tested @ 145psi and holds. Mechanical timing is correct from everything I can see ("T" mark, marks on sprocket, rocker nubs positioned correctly). Spark plugs indicate i'm running rich, which i'm ok with having heard these tend to run lean and burn up rings. I dislike starting fluid but have tried it to no effect. Vacuum lines are still stock (i think) but all connected and in good shape. Bike has ~2400km on it, 2000 of which I've put on it since getting it a few months ago. Up until now its run very well, usually starting up with one or two kicks, even @ 30F.. I also checked the oil from my last two changes and it was metal free. Im sure I'm leaving something out but ill add it if I remember Heres a video of it cranking.. when it give it some gas, ill get a faint popping sound and it definitely produces some exhaust and a compression test It seems to me like the spark is out of time.. Im reasonably competent when it comes to the mechanical side of small engines but electricity is still boarderline magic to me. Open to any ideas.. this thing is basically my car at the moment. Thanks, James
	0

08-02-2019, 12:03 AM	#4
culcune Join Date: May 2006 Location: Yuma, Arizona Posts: 9,035	Are you a member of http://49ccscoot.proboards.com/ ? Lots of scooter specific knowledge there, and they are Chinese scooter friendly. __________________ "They say that life's a carousel, spinning fast you got to ride it well..." TGB Delivery Scooter 150 TMEC 200 Enduro--carcass is sadly rotting in the backyard
	1

08-02-2019, 05:22 PM	#12
silofox Join Date: Aug 2019 Posts: 9	went to the shop this morning.. Didn't get to talk to the mechanic that I usually do but the guy I did speak to didn't think it was the CDI. He sold me a new coil which didn't change anything and said CDI would be next.. Ended up having to shut down early at work today and managed to ride the thing home. I don't think I made it above 25mph on flat but fortunately only had to go up one hill, again I slowed down to 5-10. It's also very sluggish accelerating from lights and signs. Knowing its tendency to stall, I stayed on the throttle the whole time and just kind of forced it to a stop when I had to. Finally let off it when I got home and as expected, she cut out after a few seconds. Being warm does not cause it to start easier, same ridiculous cranking marathon as if it had sat for a day. On the plus side, My speedometer started working again after hitting some bumps lol.. I have a new cable but haven't gotten to it yet as this BS started the same day I got it. Guess I'm gonna take a walk back to the shop in a few minutes.. Also, YES, the piston is at TDC when it should be EDIT: got new CDI, Problem fixed! the shop still didn't think it was my problem but it's not like they were going to refuse to sell me one.. Ended up paying $32 for both the coil and box. Not terrible for getting them without a wait, and along with some advice. Last edited by silofox; 08-02-2019 at 09:04 PM.
	1

08-07-2019, 01:19 PM	#14
culcune Join Date: May 2006 Location: Yuma, Arizona Posts: 9,035	Glad to read you solved your issues! That seems to be the thing with Chinese made scooters; you have to work on them, and be willing to work on them. They are fairly reliable; at least the engine is, but once sorted out, will give you miles of riding pleasure. __________________ "They say that life's a carousel, spinning fast you got to ride it well..." TGB Delivery Scooter 150 TMEC 200 Enduro--carcass is sadly rotting in the backyard
	2

08-01-2019, 11:58 PM	#3
benhonda Join Date: Jun 2019 Posts: 35	I've had a bad CDI box do some weird stuff before...like produce a spark when check with a spark tester but still not allow the bike to run (spark was either weak or timed wrong) and I checked a bunch of other stuff before plugging in a spare CDI box and the bike started right up. Things like the CDI box, ignition coil and pulse pickup can go suddenly on these bikes. If you ride one often, it's good to keep spares. On the upside, they are cheap. A CDI box and ignition coil together are only about $20 on amazon. Since you have ruled out fuel, and you have compression, and testing spark against the head can give a false positive...I'd replace first the CDI, then the coil...and if that doesnt fix then the pulse pickup.
	2

08-02-2019, 12:10 AM	#5
silofox Join Date: Aug 2019 Posts: 9	Thanks, I'll take a look at that tomorrow. Vehicle is stuck at work as I didn't trust it for my 10 mile ride home. The lines on the gear that he mentioned are the ones I was referring to though. They're flush with the case when I have the T lined up. Im also gonna go to my local scooter shop tomorrow morning and see what they have to say.. they wouldn't even talk about potential problems until I had done a compression test. They don't work on china bikes but they carry parts and the main mechanic there is pretty cool, very knowledgable and helpful. Any chance it could be a bad cdi? Before things got bad, it would usually start with a kick or two when cold but was a little more difficult once it warmed up. Never really figured out why but it wasn't a big problem.. by more difficult, I mean 4-8 kicks or a second or two of electric start.
	1

08-02-2019, 07:55 AM	#10
dirtbkr188 Join Date: Aug 2009 Posts: 519	I'm not familiar with that style engine, but is there relatively easy access to the valve tappets for a possible valve clearance check?
	0

08-06-2019, 11:21 PM	#13
silofox Join Date: Aug 2019 Posts: 9	another update for anyone who cares or might read this in the future.. The CDI fixed the hard start problem but the thing still ran like garbage, still giving me the same awful power and acceleration. I revisited the keihin carb that came with the thing, gave it a real good cleaning, installed and saw a little improvement. I then moved my focus to the airbox.. for as long as I can remember, there had been a piece missing (cracked off)where the intake hose connected to it. I could literally cover the box intake and feel zero suction.. guess it was worse than I thought. I rigged up a ghetto filter to that replaced the box. It took a little trial and error but I got it running ok. I could still tell it wasn't getting enough fuel and the "filter" i made didn't really do much filtering. Needing a proper filter anyway, I went back to the scooter shop but they didn't have a stock airbox to sell me so I ended up with a pod, my only option there. I also picked up a couple jets (was using a 78 main, bought an 80 and 82. Anyway, the guy messed up and actually gave me an 82 and a 90. Id already regretted not going larger so this was a happy discovery. I got everything together, also upped the pilot jet to 34 from 28. Started her up and WOW! this thing runs better than ever and sounds awesome. easily hits 40 on flats now and has no trouble keeping up with the city traffic I usually ride in. I cant tell if the plug shows me running a proper mix or if it's a little lean so i might try going up to a ~95. 90 already feels high as I live in denver @ 5300ft but I cant argue with results.. Its also been in the mid 90s pretty much every day for the past few weeks so that might have some effect on things as well. ride safe, James
	2