|
|
Post by giupalaz on Nov 3, 2010 9:50:13 GMT -5
I have a scooter Kymco People S 50 cc 4 stroke and bought some new components but not original:
• Bolt Stud 6x62 - 139QM-0122
• Tensioner GY6 50cc 139QMB 4-stroke - 139QM
• Racing Cylinder + Head Kit 47mm 72ccm - Variation:without SLS
• Nozzle 4mm (075-120) Size:0,95 - 139QM
• Rocker Arm with Holder complette GY6 -50cc 4-stroke 139QM
• Oil Seal 16.4x30x5 - 139QM
• Oil Pump GY6 50cc 4-stroke 139QMB
• Gasket Set 10" for 50cc 139QMA 4-stroke (47mm / 72ccm) - 139QM
• Cham Set 50ccm 4-stroke - 139QM
I have encharged my mechanic to install the above components but at the end of the work the scooter shows very poor performance (i.e. max speed 30 Kmh).
The suggested check of the fuel/air ratio has been done and the compression as the fuel/air Ratio and phase has been preliminary checked and were found OK.
How can I fix this?
Thank for you help!
Joseph
:help:
|
|
|
|
Post by 2strokd on Nov 3, 2010 10:00:43 GMT -5
|
|
|
|
Post by 90GTVert on Nov 3, 2010 10:29:26 GMT -5
Welcome to the site! I agree, check the valve lash. While you are doing that, you should notice if the markings on the cam and flywheel are aligned. If not, they need to be. See the link 2strokd posted for more info. While you are working on it, pull the spark plug as well and see if it's color or condition may offer any clues to the reason for poor performance. This is actually for a GY6 150's carb, but it's pretty similar to the 50cc version in many ways. It may be useful if you pull the carb apart to check the diaphragm. 49ccscoot.proboards.com/index.cgi?board=carb&action=display&thread=734 |
|
|
|
Post by stepthrutuner on Nov 3, 2010 10:57:57 GMT -5
Proper cam timing would be the most likely check to remedy your problem. Why is your mechanic off the hook for making it run right?
|
|
|
|
Post by 90GTVert on Nov 3, 2010 11:11:14 GMT -5
Good point Reg. Explaining the problem to the mechanic since it was just done would be your best course of action.
|
|
|
|
Post by giupalaz on Nov 3, 2010 11:41:05 GMT -5
All this check has been already done:
• Carburettor is ok (diaphgram in good condition)
• Air/fuel ratio is ok (spark plug lightly brown)
• Cam timing is ok
• Compression is ok
• Valve adjustment ok
Thank for you help!
Joseph
|
|
|
|
Post by 90GTVert on Nov 3, 2010 11:56:17 GMT -5
You say compression is OK. Is that from putting your thumb over the spark plug hole or did you use a guage to check it? If so, what's the reading?
Any other symptoms? Does it respond or not respond to certain throttle positions? Does it sputter or smoke or anything else unusual? 30kph is about 18-19MPH, so something's gotta be way off.
|
|
|
|
Post by 2strokd on Nov 3, 2010 12:50:18 GMT -5
Any trans or CVT work ever done or is it stock?
|
|
|
|
Post by giupalaz on Nov 4, 2010 6:17:55 GMT -5
the compression has been cheked by a gauge and shows normal
any works has been done on the cvt that is stock.
Thank you
|
|
|
|
Post by 90GTVert on Nov 4, 2010 7:08:18 GMT -5
Any other symptoms? Does it respond or not respond to certain throttle positions? Does it sputter or smoke or anything else unusual?. |
|
|
|
Post by giupalaz on Nov 4, 2010 7:39:42 GMT -5
any sputter or smoke
|
|
|
|
Post by rocketdog on Nov 14, 2010 13:07:59 GMT -5
Does it run well, as in there donesn't seem to be any problems other than it doesn't meet your expectations? Has it been derestricted? My Kymco Filly had a spacer machined into the variator boss limiting it's top speed. Sorry the pic isn't that great, but you get the idea.  That's all the restrictions my model had, but I understand others have CDI rev limiters on them. RD |
|
