Carb/Tuning Issues....HELLLLPPPPP
 

Hi everyone! I have a Bashan Storm 250 that is about 6 months old. I am very new to motorcycles and working on engines. I replaced the intake with a K&N style intake and was told I should re-jet the carb. I replaced the stock "main" 105 jet with a 110 jet. While I had the carb off, I decided to watch MotoCheez's tuning video. He suggested to modify the idle mixture as well. Mine looks different but I'm ASSUMING the below picture shows that. Well, I got distracted half way through and have no clue where it was stock and where I should put it back to. Also, it's a complete bitch to turn, is there a special tool for it or something? Pliers are definitely NOT ideal!

Anyway, I put the bike back together, getting it to start/idle is now difficult and giving it ANY gas makes it bog out and die. It runs somewhat alright on half-choke but still doesn't work right. Does anyone have any clue what I screwed up?? Should I put the 105 jet back on? I live slightly below sea level, btw. Please HELLLLPPPP! I don't know what I'm doing!!! Thanks! :thanks:

https://i.imgur.com/sCYDsOn.jpg

Had my carb on and off about 18-19 times before it was "dialed" in. Wish there was a shortcut, but is a trial n error sort of thing. Some lose guidelines are available from guys on here that know way more than me.

Would help to know if you've done any other mods, exhaust n such.

The only things I have done are aftermarket gauge and intake and remove the EPA/charcoal thing, whatever that is. As an update, I just put the 110 main jet back on there and it is starting, idling great now but still bogs really bad if I give it any throttle. How do I know which way that fuel mixture thing needs to go? Which way does it need to be turned (in or out) if it's bogging down?

Start with the idle mixture at 1 and 1/2 turns out from lightly seated then adjust from there. You will need a special D shaped screwdriver or use a Dremel or hack saw and cut a s slot for a regular screwdriver. What notch is the clip on the needle?

Mine had sat for the better part of two years.
I replaced fuel lines ( they were a bit rotten from sun) and am getting good fuel, but cleaning the carb didn't help.

Yesterday I installed a new Mikuni carb and an NGK plug.
Bike starts and runs smooth and twisting the throttle revs it up, but idle is way too high.
The info above is helpful, I'll take my Dremel and cut a screwdriver slot in the idle screw so I can back it out.

I have no idea what jet to use, I live at 6200 feet. Riding around here is 6000 to 8500 feet, but this winter if I want to ride I'll have to take the bike down to the desert, elevations there are from 1500 feet to 3500 or so.

Below sea level ? I hope you have a snorkel rigged up and waterproof everything else !
Just kidding. I am new to this carb thing myself, my last 5 bikes were fuel injected.

Perhaps back off the screw all the way out and see if you can get a replacement with a standard phillips head ( be careful, I believe there is a spring there when you back all the way out ).

First order of business for me was to buy a clone carb and rebuild kit, just to have it, its basically the heart of the bike.

I think you are going to get to a point where you strip or damage that screw and create a problem for yourself.

Get it out of there and get a regular screw in.

A good option

https://rover.ebay.com/rover/0/0/0?m...2F303210680840

If I missed something please forgive me but did you tank the gas tank off and turn it upside down and remove all the old gas and rinse with new gas?
If not do that, and I also would remove the Petcock and clean that thoroughly.

@JerryHawk250 - I'm going to try that this evening. Is there an easy way to adjust this thing WITHOUT having to take the whole damn carb off every time??? Also, we have the same bike and live pretty close to each other; do you think I should go ahead and get a Mikuni? Something's just not right with this one. I mean you (and many others) recommended a 110 jet and that just made my carb absolutely spazz out and not even start/idle! Also, do you know anywhere locally I can get this "d-shaped screwdriver" or will my only options be online?

@sandog - I PMed you but if you don't see that, the "screw" in my picture is NOT the idle RPM screw, it's the air/fuel mixture. If your bike is idling too high, there's a flat-head "screw" type of thing with a spring on it on the right side of the carb. Clockwise increases idle RPM and counter-clockwise decreases idle RPM. Just make small adjustments and listen to it. Having an RPM gauge is helpful too. I bought this one and it works pretty well: https://www.amazon.com/gp/product/B01CR2IC2Q

@NzBrakelathes - I see that's your eBay store and no offense, but I could buy a whole new Mikuni style carb for about the same price as that kit. I also don't need the sprocket as the Storm comes with the proper one.

@herbie - I really don't think it's a fuel issue. I only ever put 100% gasoline in it, the bike is only 6 months old and I rode it last about a month ago (it's been stupid hot lately).

Thanks for the input everyone! I will definitely keep you updated as to what is going on.

Not sure who would carry the D shaped screwdriver locally. If you have any problems getting it tuned I do have my original PZ30 carb that's already tuned for the stock engine plus extra jets. I have no use for it anymore if you want it.

@CaesarVis I have the PZ30 and have the same fuel mixture screw. Do NOT buy the Motion Pro D-Shape carb tool from Amazon it won't fit it's too big.


I ended up buying this but NzBrake's ebay kit version is even better. I use a small flexible screwdriver extension from Harbor Freight to reach it.


The main jet you put in won't affect the idle much. Factory fuel screw setting is 2 turns out on mine. Optimal is 1~3 turns anything else to get the highest idle RPM you should change out your slow jet.

OK guys, so here's where I am now. I took the carb off and used pliers/hemostats/tweezers to screw it in absolutely as far as I was able to...not sure if it was bottomed out or not. I backed it out 1.5 turns. The bike now idles much more stable than it did but it still bogs HARD if I give it any throttle. The exhaust also gets black when I give it throttle...what does that mean? Would a short video be beneficial to show exactly what is happening or do yall know what I'm talking about?

Check the needle clip position. It may be set on the rich side. Should be on the middle slot for starters.