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i purchased a used older bike.. i was told it ran perfectly.. and it didnt marcelo.. i ride it for a bit and it loses power then dies.. its missing the spring screw on the side of the carb.. my throttle cable broke off the carb and i cant get it back together.. ANY AND ALL HELP WELCOMED!!

PLEASE AND THANK YOU!!
 

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Okay, first things first: welcome to the site.

Do you have any pictures of your bike? Pictures help a lot on this forum for identifying what you have, and pointing out specific things. Just coming on here and saying "I have a pocketbike, can you help me?" without pictures is kinda like saying "I saw a woman shopping at Walmart, do you know her?" Since there are about a hundred different styles and models of pocketbikes, we could be here or a while trying to figure out which one you have ....

You can get a free account at a number of image-hosting sites. A lot of our members use PhotoBucket - upload your pictures there, copy and paste the links to 'em here.
 

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Looks like an mt-a2???:
Very close Nick...Thats the MT-A1 half fairing Cagllari...Its also has a 40mm cylinder judging by the fins on the head............

Losing the idle screw is bad...It makes the carb run lean and not be able to keep it running properly by not being able to have the idle set

It also appears you have RTV sealing the reedblock....RTV on intakes or anything with suction is bad..........

To fix the carb cable problem you need to make sure the lead end is still good and you have the clip that fits between the batrrel and the carb spring

To gap the coil you remove the pullstarter......

Remove the coil............Clean up coil thongs if rusty or painted...........Magnets too...

Rotate flywheel so magnets are at the 12 o'clock position facing UP

Place .020" thick strip of business card over the magnets.....

Stick coil to magnets

Add coil attachment bolts and tighten

Pull out business card strip and you now have sucessfully gapped the coil to the flywheel..

You should do the petcock mod to the carb and add a 1/4" in-line fuel shutoff

You should also mod the carb barrelslider so the rate of slider to rate of fuel is properly balanced

You should sand and polish the mainjet passageway thats part of the carb body to make the float operate without hanging up

Reset the float forks if needed and thoroughly clean out carb

Upgrade the stock tin reeds to carbon fiber or composite type and do the reedstop mod..

Upgrade the crappy Torch plug for a NGK BPM6A sparkplug..Gap is .030"

Make sure you change the carb and reedblock gaskets to insure there arent any airleaks..
 

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New throttle cables are pretty cheap.
 

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Looks like an mt-a2???
MT-A1: round frame, square gas tank

MA-A2: square tube frame, six-sided gas tank, chrome pieces down sides of frame


Nice paint job on that bike, Victor, although that chain guard looks a little sketchy. I'd try to put something on there with a little more meat between the chain and my foot ... I built this one up a while back for my avatar bike.

 

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Discussion Starter #9
**** thats alot of work.. and i just want a mini bike to ride around.. but thanks for all the suggestions guys!! greatly appreciated.. time to get to work on it..
 

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True, it's a lot of work, but you have to look at a few things concerning these bikes, Victor. First off, they're cheap Chinese copies of the real European bikes, which run in the thousands of dollars. Second, I haven't seen one of these little bikes come right out of the box and right onto the track/parking lot without some problems, usually loose bolts and/or engine problems - even the bikes I bought off craigslist all needed tuning and re-tuning before I could ride them. And third, the Chinesemade bikes are not known for their high quality ....

I'm not going to lie to you - if you want to own one of these bikes, you have to be willing to put in the time on it. That means tuning, testing, tightening and replacing bolts, cleaning the carb, all the usual maintenance stuff. It takes a while, but in the end, all the cussing, burned fingers, and busted knuckles trying to squeeze that extra little bit out of the engine is worth it.

One of the very first mods I do to all my bikes is replace all the cheap bolts in the entire bike with high quality hardened or stainless bolts. Why? Answer: reliability. I know the stuff I'm putting in is better quality than what came in it, so I don't have to worry about bolts stripping out or breaking as much as before the mod. (Since the bolts are already out, I also put rubber/metal bonded washers between the engine and the frame to help kill engine vibration ... rides like a whole different bike. Hey, works for Harley-Davidson ...)
 

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yea.. that true... but first i want to get the bike started and running.. before i do anything else.. then slowly move up from there..

so i gotta start with replacing the spring bolt on the carb(where can i buy those?) Then i gotta get the throttle cable back together and working.. casue everytime i put it together it comes apart.. i dont know if im missing a piece or if its actually broken..
 

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They don't have parts like that, a new carb is $15 + S/H on ebay.
 

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I don't know where you could find a new idle screw ... as EPR said, finding a new carb might be easier.

When you open up the top of the carb and pull out the throttle assembly, the order of parts on the cable should be this (going down from top):
-Throttle cable
-Throttle cable adjuster (usually brass)
-Carburetor top cap
-Throttle return spring
-Throttle slide (the black barrel piece)

Inside the slide (going down from top):
-Half-moon washer
-C-clip (on throttle needle)
-Throttle needle (brass needle)

Notice on the throttle slide that there is a long grove on one side, and a small angled cut-out on the other. This angled cut-out is on the bottom of the slide - the return spring goes inside the top.

Okay, to replace the cable in the slide:
-Make sure the c-clip is on the needle, and drop the needle into the top of the slide. The needle has to go through the center hole in the bottom of the slide.
-Take the half-moon washer, and place it over the end of the throttle needle inside the slide. The open side of the washer has to face the long groove of the slide. Set this assembly aside for the moment.
-Thread the cable through the top cap of the carburetor (through the brass adjuster).
-Slip the spring onto the cable under the cap and hold it there. The cable must go THROUGH the center of the spring.
-Grab the top cap between two fingers, and compress the spring until the end of the cable is past the end of the spring.
Pick up your slide assembly, needle pointed down, and slide the end of the cable through the long groove, hooking it onto the bottom of the slide.
-Release the spring so that it falls inside the slide. Your throttle assembly is now complete.

Now, the long groove faces the petcock (right) and the angled cut-out faces the idle screw (left). There is a tiny pin inside the carburetor well that MUST pass through this groove, otherwise the slide will not drop all the way down into the carburetor. If the top cap is very difficult to screw on, you may not have the slide lined up correctly (and trust me, you do NOT want to start up the bike in that situation!)

Hopefully, all this helped to get the top end of your carb back together. Sorry, no pics, but I tried to explain it the best I could.
 
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