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outlawd140

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G'day all.

I recently bought myself a twin exhaust setup for my outlaw 140. Now when I fired it up I got a greeting of spluttering up high in the rev range. So I've changed the main jet up to a 110 from a 100 and it seems to be a little better but still has a massive flat spot up top. I have also tried a 102.5 and 105 both with no luck. It is the standard mikuni carb, think its the 30mm on the outlaw.

Needle clip is at the very bottom from standard so I can't gain any adjustment from it and I only have the option to purchase 1 more jet size being the 115. If failing the 115, What other avenue can I go down. I haven't been able to find anything on here about the same problem with the same bike, exhaust etc.

Any ideas??

Cheers

Matt
 
That's what come standard on it. The bike ran 100% before the exhaust was fitted. Don't really want to change the carb out for the sake of jetting.
 
yeah the DHZ 140 Outlaws had the 30mm china Mikuni standard

what Pilot jet is in it now ?

when you swapped the new exhaust onto the bike did you replace the copper o'ring seal at the head ?
 
It's a 20 in it atm. Yeah I did change the copper o'ring. Had a lot of trouble fitting it as the pipe wasn't bent properly so couldn't get anything to line up. Had to heat it up and bend it quite a few times.
 
^dont think he wants a new carb guys......
When jetting try to keep the needle clip in the middle somewhere,
sorry I dont have an awnser for you though, I am working on it....
 
When I had my 140 I had a 24mm oko dialed in with dual exhausts.
It had better power down low and was a nice medium between a revier or a more torquey power.
You probably won't be able to sort the 30mm carb out you just be chasing your tail the whole time.
Make an adjustment to get it to run up top and it will faulter somewhere else.
Try some simple things like getting an iridium plug and better coil which will give you a better burn intern allowing you to give it more fuel which it needs but like I said I reckon your best bet is with a smaller carb with this setup.
 
Lol yeh not after a new carb. Not trying to gain figures, just want to get this thing running right. Its weird as the needle clip was set on the lowest setting already. It was going to be my first place to start playing to see whether there would be enough adjustment for improvement. Thanks guys
 
Have you done a plug chop?
Run it at wide open throttle in 3rd or 4th and turn it off.
come to a stop and pull the plug, then check the colour.
 
Haven't checked the plug. Only had it running while stationary and wrapping the throttle on. Can't really get it past about 3/4 throttle before it chokes out. Will have to have a look in the morning. I have ordered a 115 main from DHZ so will give that a go as well and see what happens. Failing that might have a cheap twin exhaust for sale!! :clap:
 
Haven't checked the plug. Only had it running while stationary and wrapping the throttle on. Can't really get it past about 3/4 throttle before it chokes out. Will have to have a look in the morning. I have ordered a 115 main from DHZ so will give that a go as well and see what happens. Failing that might have a cheap twin exhaust for sale!! :clap:

Can't really tell wether or not a bike will run well stationary mate, it may in fact behave differently under load.
I've had a few bikes that when you blip the throttle would hesitate but when riding and under load would run sweet. Try not to worry to much take it for a ride, do a chop like Craig mentioned and go from there.
 
Ive worked as a spares manager/workshop manager in the bike industry (jap) for quite a few years. A bike shouldn't flat spot at anytime. It never did previous to the exhaust swap, just thought there might be something on these things that I may have missed.

I will have a tamper with it tmrw but in my years around bikes, if it isn't running right sitting idle and you can't blip the throttle without flat spotting then it def won't work well under load. It was incredibly responsive as a standard unit both sitting idle and out on it and now I can't roll the throttle on at even a slow pace without it dying out up the top end.
 
Mikuni jets are available up to a #180 for the M5 thread jet, and a #240 for the M6 threaded jet


i would fit a new spark plug, or reuse the old one if it's not too fouled/dark colour
put the 100 Main jet back in it, and set the needle clip to the middle slot.
then readjust your mixture screw to suit the stock jetting


now give the bike a decent run, take it WOT in 3rd or 4th, turn it off, close the throttle, put in neutral and slow to a stop.
pull the plug and check the colour.
you need a tan colour, white is too lean, black or dark is too rich.
then go from there with your jetting.

i think a #110 Main jet in a 140 is too big
 
Yeah the mixture screw was gonna be the next point. I will prob give that a go 1st and see if I can pull it back in line that way. Will sus it in the AM and see what happens.

Thanks all
 
have you been adjusting the mixture screw each time you swapped the main jet ?
 
only very slightly but never noticed a massive amount of difference. Haven't adjusted with the 110 in tho as I had to leave it. Hardest thing is I don't usually get home till 7ish and live in the suburbs so constantly running/revving/or any sort of riding pisses my neighbours off. Hopefully with a full day up my sleeve I can have a good go at it.
 
The mixture screw is all ways one of the first thing I fiddle with, easy to adjust and gives you an idea of what jet to use next. When you swap jets does the engine behave differently or allways the same symptoms? Have you checked for air leaks?
 
Ok fair enough forget about my experience and opinions then all good. Hope you get it sorted soon.
 
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