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  1. #1 Got my Xian Racer exhaust and other bits, couple of questions... 
    C-Moto Noob
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    Sep 2008
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    Hello everyone!

    Just received my exhaust from xianracer as well as the Molkt carb, jets, filter and a new spark plug also.

    I have a couple of questions that I thought you may be able to help me with! When looking down inside the exhaust I see a section of the baffling in the middle which flattens out. The picture explains what i mean:



    Here you can see that the baffle flattens a bit in the middle of the pipe to form a flatter hole. Is this normal?

    And finally, how loud can I expect it to be? I can't fit the exhaust until next week, and I really like loud exhausts. What would it take to remove the baffles, if it is at all possible.

    Thanks very much for the help everyone!
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  2. #2  
    C-Moto Regular Luis Carlos's Avatar
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    I found these pictures that I believe is what you describe.


    Sundown 200cc STX motard
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  3. #3 Exhaust from Xian racer for QM200GY 
    Honorary C-Moto Guru
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    I saw that flattened out bit when I looked inside mine. I imagine it's some sort of restriction to help the silencing a bit. Being of a straight-through design they can be a bit loud at wide throttle openings. As it is the noise at town speeds and small throttle openings is not bad, rising to a pleasant loud thumper noise at higher revs.
    Jincheng Monkey JC50Q-7
    Skyteam Dax replica ST110-6
    Zongshen ZS125-43
    Qingqi QM200GY-BA Super Motard
    Qingqi QM110GY
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  4. #4  
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    Thanks a lot guys,

    Spoke to Tony from Xian and he told me its there to keep a little back pressure, which is the same as a friend said!

    All sorted then, like my exhausts to be loud so might be tempted to ttry it without the baffling after having it on a little while!

    Thank you again everyone!
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  5. #5 Molkt carb for Qingqi QM125/200GY 
    Honorary C-Moto Guru
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    Great. I thought at the start that there was something wrong with mine...by the way do let us know what results you get with that Molkt carb. I thought about experimenting with one, getting rid of the complex CV type carb fitted to my 200cc model.

    The problem was that the rubber carb adaptor fixing screws are at a 65 mm pitch and the Molkt carb only 47 mm. Even if the pitches matched, I would have to find or make some sort of insulator and gaskets.

    I notice that the 125 head is probably the same 65 mm pitch between studs but you have a sort of step-down adaptor that matches smaller carbs. This means that I could get one of those adaptors and possibly try one on mine. The only thing left would be obtaining a suitable throttle cable, as the 200 has one of those twin-cable pull-push set-ups. I suppose, once again that the original OEM 125 model throttle cable will fit.

    This is the carb set-up on the Qingqi and derivatives 125 cc models. Note that it's a normal slide-type carb ( I imagine it's a Mikuni, but not sure) with a adaptor that permits a 47 mm stud pitch carb to be fitted to a cylinder head with a 65 mm stud pitch. This adaptor also acts as an insulator, used to stop engine heat being transferred to the carb by conduction. Also note the single throttle cable:



    On the 200 cc models they go for a genuine Mikuni CV-type BST28 mm carburettor and the twin cable push-pull throttle mechanism. The carb is not bolted on, but plugs into a rubber adaptor and it's held by a round clip:



    Once again, I think it would be feasible to obtain a high performance slide carb, Mikuni or that Molkt, round about 28 or 30 mm choke plus the Qingqi QM125 carb adaptor and throttle cable and end up with a more responsive carb set-up, easier tuning, and it would be easier to remove the enormous airbox and replace it with a K&N type pod filter. This is not advisable with the CV carb. CV carbs and pod filters don't like each other...

    Note that due to the peculiarities of the CV carb, its slide substitute doesn't have to be the same choke size to obtain the same performance. A 28 mm carb can be swapped for a smaller slide one, say 26 mm without loss of airflow capabilities. This is because the internal construction of the CV carb has obstructions that need a bigger choke diameter to compensate.
    Last edited by forchetto; 01-10-2009 at 08:11 PM.
    Jincheng Monkey JC50Q-7
    Skyteam Dax replica ST110-6
    Zongshen ZS125-43
    Qingqi QM200GY-BA Super Motard
    Qingqi QM110GY
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  6. #6 Re: Got my Xian Racer exhaust and other bits, couple of questions... 
    C-Moto Not-so-Noob
    Join Date
    May 2011
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    california,usa
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    Quote Originally Posted by Rainer View Post
    Hello everyone!

    Just received my
    Quote Originally Posted by Rainer View Post
    exhaust from xianracer as well as the Molkt carb, jets, filter and a new spark plug also.

    I have a couple of questions that I thought you may be able to help me with! When looking down inside the exhaust I see a section of the baffling in the middle which flattens out. The picture explains what i mean:




    Here you can see that the baffle flattens a bit in the middle of the pipe to form a flatter hole. Is this normal?


    And finally, how loud can I expect it to be? I can't fit the exhaust until next week, and I really like loud exhausts. What would it take to remove the baffles, if it is at all possible.


    Thanks very much for the help everyone!

    hi mate ive been looking for the stainless exhaust tips and i know you are done with this trouble. im asking now for help on finding one. hoping for your help. thanks!
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