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dwint51
07-31-2013, 03:59 PM
I just hit 81 miles and my tach says 2100 rpms before the wheel starts to spin.its running great but isn't that alittle high or are my rings still tight.its a 2t 50cc

Firehawk989
07-31-2013, 06:48 PM
The condition of your rings won't affect your idle speed, the speed at which the wheel spins is determined by the clutch springs. If it's running good now, everything should be fine! You could turn down the idle slightly if it doesn't mind when warmed up, usually you want it around 1800 hot I think. It will run faster when cold because of the enricher.

These little guys don't idle at 200RPM like a Harley! :D

dwint51
07-31-2013, 09:08 PM
I only use it on short trips.thats why its not even getting warmed up by the time I get to where im going.

skuttadawg
08-01-2013, 11:31 PM
Always let a 2T warm up for at least 30 seconds prior to riding and up to a few minutes when its winter time . When new try to avoid long idles , as it will not help the break in and also avoid running at the same RPMs for a long duration as well no redlining . I bought a 2T scooter as was excited as it had been 20 years since I had a 2T and I hated the 4T 50 I used to have . I started off going around the block and secondary streets , but wound up riding all the way to another county as I did not wan tto stop riding it . Focus on getting up to midrange and go up and down with the throttle to change the RPMs and be easy going downhill . When new the piston is tight and after 500 miles or more you should be able to tell it will run with less friction and perform better .

A 2T runs a higher RPMs than a 4T . I can not recall what RPMs mine engaged when it was stock , but I now have a BBK and 1.5k clutch springs that engage at 1,500 more RPMs than the stock springs in order to have more take off power

blueboy5000
08-02-2013, 10:28 AM
Here's the deal with idles;

As high as you can get them WITHOUT the rear wheel moving when bike is on centerstand WHEN BIKE IS FULLY WARMED. Always start a cold bike on it's centerstand. A cold bike will rev higher than it's idle, high enough to spin the rear wheel a good amount. This is normal, and is the result of your ENRICHER. When the bike is fully warm (5-10mins) the rpms will return to what you set your idle at.

2-Ts like a slightly higher idle (1800rpm or so) than 4ts (usually 1600rpm).

But it is not unheard of to set either at 2000, it really does not matter where you set the idle as long as the rear wheel does not spin when on the centerstand.

To high of an idle will create "surge" at stops and will glaze your clutch bell and friction shoes. I would go so far as to say too high an idle is the #1 cause of clutch problems (well okay # 2, belts is #1)

dwint51
08-02-2013, 12:50 PM
this carb on mine has one screw on it.ive never seen anything like it.turn it to the left the idle goes down turn it to the right and the idle goes high.so if this is my idle screw where would the air fuel mixture be.its hard starting seems to be flooding out.when it gets warm it will start probably cause its getting lean.how can a carb have only a idle screw and not a mixture screw

skuttadawg
08-17-2013, 12:11 AM
Your mixture screw may be covered up like many are . Luckily mine was not and the idle screw is so big that I can adjust it with my fingers . When seasons change you may have to adjust the idle . Always let it warm up by riding around a bit before adjusting the idle . When it is cold sometimes mine will idle high for a minute or two then idle down on its own .

Should not turn the wheel on the CS at idle unless the choke has it running at a few more RPMs . Sometimes mine would want to want to spin the wheel but not a full engagement . Now you can get stiffer clutch springs like the 1K , 1.5k or 2k , which these engage at their rating that much above the stock springs . 1k the clutch engages at 1,000 RPMs more than the stock ones . 2k may be too much as it will wear out the parts faster and can have you popping a wheelie . I use 1.5k since I wanted to try 8g sliders to reduce the RPMs at cruising and top end . Most use 4g . I had 5g when it was a 50 but with a BBK it was too light . The 8g only slowed down the takeoff as I can still hit 9k RPMs going up a steep hill with a running start . So it looks like I will have to get taller gears as I want to tune it for long rides and hope to get better MPGs .

See what size idle jet and venturi you have and try a size up IJ . Mine had a 40IJ and I would have to give it throttle to start and during a long idle as I had to adjust the idle screw every 2 months . With a BBK it got worse even though it ran great while riding . I went to a 45IJ now it starts with no throttle and idles perfect . It was easy to find main jets as many use Mikuni VM11/22 but my TK carb had an oddball IJ and I only found it at one place . It does cost a bit retail but worth it . If you can get or know someone with a commercial account it will be much cheaper . Here is the IJ if yours has a TK (Teikei )
http://shop.jupiterscooters.net/Idle-Jet-45-for-TK-carburetors-MGMP-JET45TK.htm

I also am enjoying the 47mm BBK from MODCycles with 10mm wristpins . Looks like the Hoca kit , has way larger ports than the 50cc did along with a full ported exhaust port . The 50cc was shaped like a D instead of an O , so it restricted it from getting high RPMs . 50cc would max at 8k and if I went higher than that downhill it would fizzle and stall . Even a racing CDI made no diff on top end RPMs . With the BBK , Uni and a racing pipe with no baffle it can not hit 10,500+ but I try to not go above 9k to be safe .

2Ts will always need to warm up prior to riding , more so in winter . I rev it up just a bit on CS which also warms up the belt too . Only rev it up just enough to get the tire spinning and NEVER race up a cold engine . A NGK iridium does help it start and run better than a standard plug , but will not make it go faster . I use NGK BRP8HIX since it is a cooler temp plug than the BRP7HIX which some in cold climates may use in the winter . Winter seldom gets below freezing where I live

skuttadawg
08-17-2013, 12:12 AM
Forgot to say mine sometimes seem like it would get flooded so I bent the float valve and it fixed it

Frank Castle
03-03-2014, 07:17 PM
Forgot to say mine sometimes seem like it would get flooded so I bent the float valve and it fixed it

whats a float valve?