All 2st Jetting Chat - Need Help? Post Your Questions Here

LoL@Johnny...read your own posts and l'm sure you know your way around carbs

PS. Love to help you but l don't have much experience with Mikuni's.

Not sure what the actual fuel level is supposed to be. I lowered my float 3 times. Even the stock TMXX was set too high and both 36mm and 38mm Keihin PWK a/s.

I also noticed early in the enduro that on another hill that I had to slip the clutch and the engine just didn't want to respond and increase in power or speed when under a load.

Yes, i know jetting, but thought i would take the easy way and see what mods is required. I heard about exhaustports for example=). It feels weak, but it,s a 125, i know. I,ve been riding my ported Honda CR 500 for a while, so i guess that could be the cause of "feeling the weakness" too=)!

Johnny

If you move your clip one move and don't like it. Try 1/2 clip shim and see what happens?

Johnny...just don't get too use to the Wr125 or else you'll jump on the 500 and be the first man to do a double backflip standing still

Aahahaa! Yes, that,s a risk for sure! The 500 is something you have to respect. Wheelies in 3rd gear at 55mph on just throttle with 14/38 gearing=). I will make a dynorun on the 500 in the future, and then i can post the graph.

Mine is running perfectly through the entire range but the fuel mileage is suspect. I'm keeping track of the next tank or two to see what it actually is before I cry wolf. I kept lowering my level until it started running out of fuel at sustained wide open throttle in 5th, then I went back up with the level so that just before the peg touches the carb pees on the ground. The woods I ride on my property is 80% 1st gear logs rocks and bark scraping jungle with a few short bursts in 2nd and 3rd so maybe I'm asking too much for fuel economy. (I've been trying to get a trials ride organized as it suites that use better and may help ride in some new trails.)

My 09 is different, screw type no reserve

It's funny that you should post this because last week I was working on jetting and my 09 WR250 acted like it was running out of fuel so I turned it to reserve and finished riding later when I got back to the house I discovered that it still ha 1/2 tank of fuel. This matches your description exactly.

Have you looked to see if you can drill the spout out a little more?

Thanks, Will do. Wonder if I will have to drop the Main back from a 172 to a 170 ? I guess if it isn't blubbering it will be OK.

Sending a pic of the Honda 500=). Gixxer, so what you are saying is that the WR 125 also could be restricted in the fueltap? Is that right or am i just bad at reading?

Johnny

I don't think it is the petcock. Mine is screw type. Anyway if I want to run the bike out of fuel for storage it will run for several minutes once petcock is turned off.

I would think your main can stay the same.

Rode a H/S this weekend. My power / jetting problems fixed. Lowered clip on needle one slot to raise the needle to the #3 position. No more flat power. The H/S this weekend had a LOT of long uphills. I am still wondering how the promoter got more up hill climbs than down hills in a 11 mile course. LOL. My WR150 pulled all the hills with ease. Yes, my main jet stayed a 172. Bike ran great. I rode terrible. But, never fell. Course was slippery due to all the rain before and during the event. The tropical storm brought in a lot of bad weather.

Hi Johnny, yes this is what i was thinking

Interesting, the whole setup is gravity feed so you really have to measure the flow rate when the tap on 'ON' vs 'Reserve' in order to determine whether you have an issue that the 'ON' level of the petcock remembering, that the length of the tube of the 'ON' position of the petcock determines the point where you will need to manual switch to the 'Reserve' which operates that the bottom of the tank.
Not saying that you are wrong but I would have thought that these tubes are the same diameter..have you experimented taking the gauze off?

I've been kind of folowing this to see how it came out. Glad you got it fixed.

2011 wr300.

first got the bike it would cover the rear of the bike in oil and was a pain to wash, took it back for its first service and told them i think it was running a bit rich (all i wanted was the bike not too spit so much oil) my 99 rmx 250 never spat oil. They changed the air screw or air/fuel mixture screw (im not good with jetting very new to this). Since the change it has killed the performance doesnt have a hit or a power sling shotting you forward basicaly tamed it down and killed the fun factor.... so everything is still stock all they did was touch that one thing and it made a big diffrence. Not a wild front wheel lifting machine anymore.... so any advice before i try and do it myself? have the bike running? quater turns, half turns, full turns? how much diffrence does this adjustmeant really make?
a 300 two stroke should go harder then what it is atm...

My 2010 WR300 would hardly even run with the stock jetting. I am at sea level and I changed my jetting to gay needle (it actually says the on the side of the needle) 2nd slot down from the top, 40 pilot, 440 main, and air screw 2 1/4 turns out. I'm not sure if your bike comes with an extra needle and jets from the factory, but the bikes sold in the states do. Also, I run Dumonde Tech oil mixed at 50:1. You will need to pull the fuel tank, remove the rear brake reservoir to move it over, loosen the jam nut on the top of the carb where the throttle cable attaches, loosen both clamps on either side of the carb and then you can turn the carb enough to get to the needle through the top (two screws hold the top, and an 8mm holds the needle in the slide), the main and the pilot are on the bottom (17mm wrench to take out the plug on the bottom). This will get you in the ball park at sea level.