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Check the baffle isnt carboned up there will be a small screw right at the end of the outer skin of the muffler. Undo it and pull the baffle out....you may need to persuade it to come out if its rusted. Check the baffle for carbon build up.....you can run the bike without the muffler on to see if this helps. Use a blowtorch on any carbon bulid up.

Two strokes need compression for fuel transfer so if its low, (crankshaft seals) starting may be difficult. If the bike is hard to start once warm then it may be due to some loss of compression in this area...oil smears around the bottom outer cases might also be an indication of this. Carburetion can be a problem...check the oil pump isnt oversupplying...an oiled plug, (fouling) will be evident.

The initial setting for most carb jets is around one and a half turns out from light bottoming of the jet tips. I wouldnt think the rebore would make any difference to the fuel ratio so changing to a larger jet will not be an issue. Your throttle needle may be adjustable...a small circlip fits into one of several grooves in the top of the needle...raising it enrichens the fuel...lowing it leans the fuel.

Be very careful if you lean the fuel ratio out...two strokes are very susceptable to burning a hole on the piston top if run too lean. A spark plug chop test may be needed.

To do this you take the bike out to a straight bit of road and ride it at hight throttle settings....you dont need to speed just stay in second or third and get the rpms up. Stay riding for about two to five minutes then cut the ignition while pulling the clutch in so the motor stops dead. Then pull the plug and check the colour...watch out it will be hot! Light coffee brown is what you want...white is too lean and black/sooty is too rich.

Any oil on there is indicative of either worn bore....in your case not likely.... or broken ring/s....possibel. One other thing is did you rotate the rings around so the gaps were not aligned?

Finally What is the air filter/spark plug condition. The spark...needs to be fat and blue...anything less is suspect...it may be the cable/either boot/cap or the coil...even the current supply may be a bit iffy so all connectors need to be tight and clean. Check the connections to the CDI unit are clean and tight.

Hope this helps and good luck
 

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Discussion Starter #22
Technique can be important.

Make sure that the choke is closing.
Make sure that you are NOT twisting the throttle at all; it needs to be fully closed.
Crank it for a few seconds and then crack the choke open a tiny bit and crank again.
DO NOT OPEN THE THROTTLE until you hear it fire.

P.S. Having the idle speed set too low can hamper cold starting too.
I'll keep all of this in mind when I keep trying to adjust it this week, finals are over and it's finally spring break! I'll have a lot of time to mess with things. Can having the idle set too high also mess with cold starting?
 

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Discussion Starter #23
Check the baffle isnt carboned up there will be a small screw right at the end of the outer skin of the muffler. Undo it and pull the baffle out....you may need to persuade it to come out if its rusted. Check the baffle for carbon build up.....you can run the bike without the muffler on to see if this helps. Use a blowtorch on any carbon bulid up.
I just bought the muffler a couple months ago so everything looks pretty good there, except it has a small hole near the engine. Could that be affecting it enough to make it this hard to start cold??

Check the oil pump isnt oversupplying...an oiled plug, (fouling) will be evident.
My oil pump is broken so I've been mixing the suggested amount from the service manual.

Be very careful if you lean the fuel ratio out...two strokes are very susceptable to burning a hole on the piston top if run too lean. A spark plug chop test may be needed.
I've been slowly leaning it out (turning the screw out by about 1/4th turn every time I ride) to see if that can help it start. I'm thinking if I can get it starting well then I can do what you said below to make sure I'm not too lean. I've been getting this a lot from the forum and the shop I go to so I'm being super careful not to make it too lean! :)

Finally What is the air filter/spark plug condition. The spark...needs to be fat and blue...anything less is suspect...it may be the cable/either boot/cap or the coil...even the current supply may be a bit iffy so all connectors need to be tight and clean. Check the connections to the CDI unit are clean and tight.

Hope this helps and good luck
Air filter and spark plug are both brand new... but I'll pull it when I go to make some more small repairs this week. Maybe that will give us some more clues.
 

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If cold starting is the only problem then I would be checking the choke is actually working...not too sure but most of that era are simply a butterfly plate in the inlet of the carb. One other thing is to check the idle circuit....the tiny jets just after the venturi are used to assist cold starting too. Another point...is the carb a Cv type or the old slide type. Many CV types have a small 'o' ring fitted to the top that is directly associated with the choke mechanism.
 

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Discussion Starter #26
Sorry for the late response, but I got everything working! It cold starts perfectly (in around 8 kicks) and it runs sooo well! :) There isn't as much power as I think there should be in the higher rpms but I think that might be a jetting issue. I couldn't have done this without all of your guys' advice and help, and I can't thank you all enough!!

My next mission is to get the electronics working (turn signals, tail lights, etc.), hopefully that doesn't prove as difficult as this was hahaha
 

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Sorry for the late response, but I got everything working! It cold starts perfectly (in around 8 kicks) and it runs sooo well! <img src="http://www.motorcycleforums.net/forum/images/smilies/icon_smile.gif" border="0" alt="" title="Smile" class="inlineimg" /> There isn't as much power as I think there should be in the higher rpms but I think that might be a jetting issue. I couldn't have done this without all of your guys' advice and help, and I can't thank you all enough!!
So what was the final solution?
 

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Discussion Starter #28
Just carb adjustments. A friend of mine helped me out and with the bike warmed up he turned the mixture screw left until it revved up and then right when it started to drop he lowered it half a turn. He then upped the idle and now it runs really well
 
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