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Did basic mods, TTR 230 not quite right yet.....help!!!

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I did a successful upgrade to the bike via the jetting (pilot and main, along with air/fuel screw), air filter and exhaust. Bike notieceably runs alot better and not the dreaded warmup times. My only question is that after I run the bike for a while and twist the throttle very quickly while idleing, I still get the cough, sputter, etc. What I did notice was that the mods recommended here on the site said the fuel air screw should have been 1/4 turn out from bottom in stock form. When I did drill out the plug, my stock setting must have been 1-2 turns from the bottom easy. I buried the screw and backed out 1 full turn. Based on my description above, will turning out another 1/2 turn help my sputter and coughing when I quickly twist the throttle? A "normal" turn of the wrist is fine, it is just when I really twist quickly.

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This solution is easy but time consuming. Your'e on the right track. The solution is a proper fuel screw adjustment. The screw isn't easy to reach so take a stubby or pocket screw driver an saw it to fit. Paint a mark on the handle so you can see how far you turned it. Only turn it one eighth of a turn at most and try it out. Keep doing that untill you get the perfect throttle response. I think mine ended up one half turn out from the seated position so that might be a good place to start.

Don't get carried away with this and let it idle too long. I don't want to get blamed for a seized piston.

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Before you go fine tuning, make sure the coarse setting (pilot jet size) is right. Follow the instructions "dialing in the pilot" on this page: http://articles.superhunky.com/4/55

If you get the screw the whole way in or it is turned out excessively, you'll need to change it and all the screwing around with the mixture screw won't change it.

You could also try dropping the needle one clip too. That would be my guess, but it's more of a pain to do that than it is to test your pilot jet setting first.

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Before you go fine tuning, make sure the coarse setting (pilot jet size) is right. Follow the instructions "dialing in the pilot" on this page: http://articles.superhunky.com/4/55

If you get the screw the whole way in or it is turned out excessively, you'll need to change it and all the screwing around with the mixture screw won't change it.

You could also try dropping the needle one clip too. That would be my guess, but it's more of a pain to do that than it is to test your pilot jet setting first.

ALERT! The page this poster linked to describes a carb with an idle air screw. Correct me if I am wrong, but the TT-R230 TK carb has an idle FUEL screw, so tuning would work OPPOSITE of what was described in the linked article.

I would offer this advice for determining the correct pilot jet and fuel screw setting:

Bring the motor up to normal operating temperature. Raise the idle with the throttle stop screw to something around 2000 - 2500 rpm - faster than a normal idle, but not racing. Turn the fuel screw in until the idle drops. If the fuel screw turns all the way in without the idle dropping, the pilot jet is too big. If the idle does drop before the screw reaches bottom, turn it back out until the idle drops again, counting the number of turns. If the idle doesn't drop again before the fuel screw is backed all the way out, then the pilot jet is too small. If the idle does drop, your pilot jet is ok. Turn the fuel screw back HALF the number of turns between the two points where the idle fell. Lower the idle back to normal with the throttle stop screw.. Ride away happy.

If you have done this, you will have a very good idle mixture, and best response from low RPMs, but it may not totally get rid of bogging when the throttle is whacked open. Here's why - This carb is not a CV carb, and it doesn't have an accelerator pump... it can't maintain a proper mixture for very quick throttle opening at low RPMs. It's an old school carb. You have to open the throttle smoothly to get the best power. This is how grandpa learned to be so smooth - he had to or his bike stalled out.

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i have the same problem and tryed all that but when i hit woops hard it seems like the bike is cutting out

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If you set the fuel screw at about 1.75 to 2 turns out to start, you will probably never have to change it.

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so you're just rapping from 1/3ish to WOT? there's no accel pump so ofcourse it's going to happen, my 125 in perfect order (intake wise :) ) does the same thing, and it doesn't have an accel pump my 250 does and it doesn't do that thing!

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