I've been working on an LT230E that my friend bought for 80 bucks for a month or so on and off now. When he first brought it to me it would only start with the choke on fully and would idle nicely until either you touched the throttle or turned the choke off. Since then i have rebuilt the carb, and cleaned it a couple times while testing it afterward. The bike will now start very easily with the choke off and idles well. Off idle it revs better in reverse than in forward gears. At times it has ran perfectly for me, but now since i have cured the choke problem (bad o-rings) it hasn't. Here's a list of the symptoms:

-Revs up better in reverse than forward gears
-Backfires, bogs, sputters at over quarter to half throttle in gear only
-Sometimes runs perfectly for a short period of time (cold or hot does not affect this)
-At times it still acts like it wants to die when i hit the throttle, it is very rare but none the less it does happen, almost as if it loses electrical power or something from it.
-I can power brake it and apply the throttle fully without it bogging.

It has 3000 miles on it and idles strong with minimal engine noise. Any ideas?

 

is it the stock size carb and stock exhaust? if you have some money and mechanicly inclined spend 100and buy a top end kit i just did it to the exact same quad about a month ago and i had some similar issues but not all of them and ive had no symptoms since its a very easy rebuild, and cleaning the head and valves always does some good

 

Yes, the carb and exhaust are both stock, although the muffler has seen better days. I've removed the valve cover and checked that its in time. The rocker arms and cam lobes showed no signs of wear.
Another question, while going through the wiring i came across a small bottle under the switch assembly. Further research showed it to be a coolant bottle. Is it supposed to be hooked to something?

 

i still don't know what that coolant bottle is for, maybe nothing, but i did get it running right. it turns out the carb was the problem. i bought some old messed up carbs off ebay for next to nothing and rebuilt one with parts i already had. the choke plunger was the problem i think, as the carb i put on had it sealed in with epoxy. i found a place online to buy carb parts for this bike as well, heres a link. thanks for the help guys.

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