|
|
Post by racingrandy on Jun 28, 2011 21:19:02 GMT -5
To give you a quick background on my knowledge, I've sold over 100 scooters over the past few years (mostly two stroke) and recently got back into the scooter business selling 50cc Tao Tao VIP scooters with GY6 engines. I've been able to fix all the minor problems I've had in the past. I've been working on cars my whole life, as a hobby, and own a 1968 Camaro convertible and 1941 Plymouth Coupe street rod. I have a good knowledge of basic troubleshooting, but these new scooters have me at wits end.
Here goes... Once again these are 50cc Tao Tao VIP scooters brand new out of the crate. After assembly, oil change, high test gasoline, and break in I take them for a test ride.
After roughly 6 or 7 miles at higher speeds I start to hear an occasional "spark knock" as if you're not running high enough octane gas in a car.
At this point if I continue at higher speeds the "spark knock" becomes worse. Continuing to ride, especially on an uphill grade it will get to the point, within the next mile or so, where it acts like it's running out of gas. If I pump the gas I can continue at about quarter throttle, but any further and it acts like it doesn't have enough fuel to support the request and falls on its face.
If you don't ride them at higher speeds, except for a mile or two here and there, this problem doesn't happen near as much, if at all.
I've tried riding without the gas cap, bypassing the fuel filter and valve, adjusting intake/exhaust valves, new carburetors (they seem to fix the problem but don't run very well), new spark plugs, among other things.
When it does get to that point of hardly running, it is running lean. The plug is fairly white. When running normal it is slightly lean, but seems to prefer it.
Of the dozen scooters I've purchased, most of them have had this problem.
I would greatly appreciate any insight into how I could fix this problem. Thanks for your time.
Sincerely,
Randy
|
|
|
|
Post by edfr on Jun 28, 2011 21:29:18 GMT -5
Have you tried 87 octane gas, how high is the High Test Gas? High Octane Gas does not burn as fast as the lower octane. High test is usually good for high compression engines to slow the burn. You could be running to lean and causeing a soft seize I would richen it up just a little to be on the safe size.
Lefty
|
|
|
|
Post by racingrandy on Jun 28, 2011 21:36:28 GMT -5
These are 2011 scoots with anti-tamper carbs. The bowl has anti-tamer screws and the air/fuel mixture screw is plugged. Yes I have used 87 octane and have the same problem.
By the way, if I leave it sit for around 10 minutes I can go through the whole process again.
|
|
|
|
Post by ltdhpp on Jun 29, 2011 11:53:21 GMT -5
Some one here posted a link to an article where someone determined the 50CC VIP's got some bad casting/machining for the spark plug hole that somehow made it act up when hot. I cant remember if some just used a different (longer?) plug or just got better heads for them.
I recently rented one that did the same thing, lots of threads here about the same scooter/problem
|
|
|
|
Post by noday on Jun 29, 2011 13:12:59 GMT -5
I bought a cy50-T3 about a month ago. (same engine and carb) did a minimal ride before changing a few things including the carb. The carb was jetted very lean, the pilot jet (idle) was 30 or so. main 70, needle not adjustable. pulled/removed the epa stuff & capped the port into the cylinder case. replaced the carb with one fully tunable and upped jet sizes to 34/88 with a free flow air filter. replaced the 2 port stock intake manifold with a single port type so that the only vac line is straight to the fuel valve. the epa stuff may well be allowing an intake vac leak. didn't run it enough stock to fully check this out as that has always caused problems in the past on other scoots so I removed it up front. I expect you will have do something similar to get good performance. when you change carbs you will need to find the right jet sizes. that is usually somewhere around 34/74 with the stock restricted air box. you can drill the tamper resistant float bowl screws out. that smooth head is only about 1 to 1.5 mm thick. the brass cap over the A/F screw also drills out easily. you need to rig up some type of jig to hold the carb steady for a straight shot. I used an old wood working vise and a drillpress  |
|
|
|
Post by mainepeace on Jun 29, 2011 14:16:15 GMT -5
The 2011 carbs generally DON'T have an A/F screw in there, it's a plug to nowhere. The issue with the Peace Sports VIP was that the spark plug hole wasn't drilled deep enough so the spark plug so they would die. I've had the issue with spark plug blowout from the crappy Torch spark plugs.
If you can drill out the screws to the carb bowl, I'd try to swap in a larger main jet. It sounds like it's running very lean. The only other thing is to somehow block off the intake a tiny bit to restrict the airflow.
Greg
|
|
|
|
Post by edfr on Jun 29, 2011 15:18:53 GMT -5
The problem with the Other Scoots was the Head, It was to thick where the Spark Plug hole was so the Plug was Actually NOT PROTRUDING into the Head. So at WOT it would when a Spark is really needed it was partically grounding out on the inside threads. The manufactuerer sent him NEW heads properly ground around the Spark Plug hole so that the Plug reached inside.
Lefty
|
|
|
|
Post by waterjunk on Jun 29, 2011 15:45:56 GMT -5
We have been selling the VIP's like crazy for the past few weeks. I might have gotten lucky or the customers may have not rode hard enough but i havent had any complaints as far as that problem.
Before I send them off i usually swap out for the cr7hsa ngk plugs. Maybe that helped avert the problem.
How is that cy50t3 running for you noday? On the pictures they look ugly as hell but i saw one in person and they are definatly pleasing on the eyes
|
|
|
|
Post by dyoung1167 on Jun 29, 2011 16:37:34 GMT -5
the others seem to have the problems figured out but you should go to harbor freight online and pick up a set or 2 of tamper proof bits. only a few dollars a set and come with all the standard types, such as star bits with a whole in the middle, and the ones that look like phillips head but only 3 sides, etc.. very much worth the money even if you just want to mess with the people at mcdonalds.
|
|
|
|
Post by noday on Jun 29, 2011 17:19:11 GMT -5
hey dyoung... the tamper proof bits do not work for these carb screws. they are shear-shaft or break away type... the top of the screw head is smooth & recessed flush into the rim of the carb.
you either cut a slot in the smooth head or drill em out.
for waterjunk... I have had no problems with the CY50T3. It does not really look like most of the online pics. It looks pretty much like a Tank Urban 50/Jonway QT-6 except with 12" wheels and dual rear shocks. Mine is orange. Just a normal sport style scooter.
|
|
|
|
Post by dyoung1167 on Jul 4, 2011 11:47:45 GMT -5
ok, i was thinking of normal tamper proof,sheesh, why would they make it so hard? i'm glad i don't have one.
|
|
|
|
Post by Premier Scooters on Jul 4, 2011 13:02:12 GMT -5
I've been opening the carbs with a easy out. On the screws I cant get out that way I put a slot in them with a dremel cut off wheel and use a flat blade screw driver. It is annoying but you can still get in there. The stock Tao Tao jet is a 78. Put a 85 main and a NGK C7HSA. It will solve the problem.
|
|
