Messages

1

Technical / YZ125 jetting questions.

« on: March 18, 2012, 12:49:05 AM »

i got it figured out. When i first bought the bike i messed up the stator being a dumbass. Anyways i bought an 06 stator and the cord was too short so i had to splice in the 05 harness to make it long enough to reach the cdi box. When i spliced it i used krimp connectors, and one of those had come loose causing my whole problem with jetting. I took it all apart and soldered the connections and it runs like a completely new bike. It just keeps pulling.

Thanks for all the help guys now it runs like a dream, wasn't even jetting after all.

2

Technical / YZ125 jetting questions.

« on: March 16, 2012, 12:01:09 AM »

Ive done everything. i really am starting to think its electrical. I get great power up until just after the powerband and it just bogs. It feels like its not getting spark and it cant burn the fuel. Im going to check all the connections and see what it can do.

3

Technical / How do I slow down my idle?

« on: March 14, 2012, 02:02:34 AM »

Check and make sure your throttle cable isnt out of adjustment or sticking. It could have too much tension on it causing it to be on the gas a little.

4

Technical / YZ125 jetting questions.

« on: March 14, 2012, 12:07:57 AM »

so this whole time ive been trying to jet this bike and i cannot get it right. Im thinking about putting everything back to stock and running 32:1. Its at 40:1 and I put a 37.5 pilot 2 screws out, tried a 400 main and it felt too rich,sputtering at full throttle, went up in the needle still too rich. Tried 390, too lean got surging and a light plug.

Any advice? im stumped on where to go from here...

5

Technical / YZ125 jetting questions.

« on: March 12, 2012, 01:22:55 AM »

Ahh man thats no good, but it sounds like you got it figured out.

If i was mixing 32:1 i would go back to 410 on the main, so i think you'll be happy with the jetting you got.

Im at about 2200' above sea level, and temps ranging from 60 to 80 f lately.

6

Technical / YZ125 jetting questions.

« on: March 10, 2012, 06:48:41 AM »

Im in San diego, and don't mess with the float, unless its obvious its the problem. I did and ended up putting it back to the way i found it. Anyways, right now im running 400 main, 37.5 pilot air screw about 2 turns out, and clip at 3rd.

I have some surging and hesitation at about mid throttle if i jump on it from low rpms. It kind of bogs then picks up, i think moving the clip back to 4th position will solve this and then it will be spot on. Plug tests so far show signs of great combustion, not lean, not rich.  The repacked silencer, new top end and the current jetting make it worlds better. Best of luck!

7

Technical / YZ125 jetting questions.

« on: March 08, 2012, 10:38:14 PM »

so i just got done cleaning the pipe. I used sodium hydroxide drain cleaner crystals, and it didnt do anything. literally came out a slight hue of brown, no carbon taken off nothing, and the stuff burns your skin and takes the paint off your pipe. Waste of time. I ended up putting a piece of cable on a drill and spun it/ rinsed like 5 times. That worked really well. So my advice, just either burn the carbon out or use a piece of cable and a high power drill.

Im trying 400 main, and 3rd position clip for the jetting. When i checked the air screw it was like 4 turns out so i adjusted that back to 2 1/4 and i set the float height.

going to do the heat cycles and plug testing tomorrow i think. still have to repack the silencer, change tranny fluid and refresh coolant.

8

Technical / YZ125 jetting questions.

« on: March 08, 2012, 03:30:01 AM »

For sure, ill take a bunch of pics.

9

Technical / YZ125 jetting questions.

« on: March 08, 2012, 01:55:17 AM »

Got a 390 and a 400 main to try out. still have to finish up on the silencer and top end. Also i bought some drain cleaner to attempt to clean out the head pipe, going to give that a try because if its anything like my powervalve was it has to be robbing some power.

Thanks for the advice!

10

Technical / YZ125 jetting questions.

« on: March 07, 2012, 06:28:35 AM »

Hey everyone, Im new to the forum but i have been lurking here for a while, great stuff.

Anyways, a few months back I ditched my  07 yz250f 4 stroke and picked up an 05 yz125. Relatively new to these 2 stroke beasts but i couldn't be happier with my decision.  The only thing is I noticed alot of stuttering and cutoff in higher rpms. It just doesnt sing like it should. It idles perfect, for about 8 seconds and the mid range power is fine though. I am in the process of doing the top end and could use some insight onto where to go from here jetting wise. When i opened the powervalve top it was packed full of gunk unburned oil. Im almost positive its running too rich. The plug is black and wet and the piston doesnt look to great, and i think it was a contributing factor to the poor operation in higher rpms.

I am looking for some advice on where to go from here, runing 40:1 maxima K2, jetting is stock, 410 main, 40 pilot, 4th position clip. Along with a new top end, the silencer is going to be repacked, reeds cleaned and checked, powervalve cleaned so i have a fresh base to jet off of.

also, i notcied some pretty bad blow by on the piston, the ring was out of spec aswell.

So what do you guys think? Rich? what to change first? any help would be greatly appreciated!
















And heres the bike just for some eyecandy