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Author Topic: Back fireing  (Read 3067 times)

Chris0381

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Re: Back fireing
« Reply #15 on: May 12, 2016, 10:31:40 AM »
Exhaust leak at the flange ?? Incorrect fuel mixture ??

A little google of scooter backfiring came up with those.
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2013 Super 8 50cc 2T Air Cooled Mfg'd 2012
Stock pipe derestriction
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6.5gm Dr Pulley sliders
Malossi Torsion Controller
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#95 Main Jet
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42 MPH on the flats with the wind

blue

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Re: Back fireing
« Reply #16 on: May 12, 2016, 08:13:36 PM »
Quote from: pipster326 on May 11, 2016, 08:22:02 AM
Gentlemen, I need some advice. My DT 300i is a 2012, I got it in October '15. It has less than 1800 miles. I noticed these little cracks in the tire. I don't know how or where it sat before I bought it. Should I replace the tires? Or should I wait? You guys have helped me in the past, I trust your opinions! Thanks 

    - Rich


Sent from my iPad using Tapatalk  its all good have a cup of coffe on me.....your tires are weather checked.I would get new befor you are left pushing the scoot home.
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blue

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Re: Back fireing
« Reply #17 on: May 12, 2016, 08:18:29 PM »
Did some fine tuneing today. Soon as I turn the gas mix screw to about 11/4 turns the scoot runs its best. But only gos 30 to 35 mph...with it 21/4 turns or less I can do 40 to 48 but then the back fireing starts.....Look like I need to go up a size in my main jet.
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CROSSBOLT

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Re: Back fireing
« Reply #18 on: May 12, 2016, 09:05:13 PM »
That mixture screw usually is for idle speed. You are on the right track with a larger main jet.

Karl
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Karl

Three motorcycles 1960-1977 (restored a 1955 BSA)
Agility 50
Yager 200i
Downtown 300i
Navy tech, Ships Engineer, pilot and aircraft mechanic

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Re: Back fireing
« Reply #19 on: May 21, 2016, 11:17:42 PM »
Ok back to the backfireing.I pluged off the big hose that comes from the bottom of the main head.took for a small ride.and the back fireing is gone. What gives. Is it safe for the scoot to have this pluged up.
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blue

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Re: Back fireing
« Reply #20 on: May 22, 2016, 01:32:46 AM »
Pic.
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xsel777

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Re: Back fireing
« Reply #21 on: May 22, 2016, 06:18:57 AM »
Pipster , If that is a maxxis tyre, run as far as you can from it.
I had maxxis on my 500 which also developed cracks like that,  but even worse, one right across the circumference.!
Also I noted that the front tyre developed uneven wear pattern.
In  my opinion, they are an inferior product.
Since changing to Michelin city grips, all such problems are non existent.


 Sent from my Samsung Note 3 with Tapatalk
« Last Edit: May 22, 2016, 06:21:21 AM by xsel777 »
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2010 Kymco Xciting 500Ri-Dark Blue

2wheelfun

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Re: Back fireing
« Reply #22 on: May 24, 2016, 12:11:40 AM »
Back firiing = timing on most problemos, =premature/after detonation. Just a cause maybe?
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