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  #21  
Old 10-12-2016, 08:32 PM
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I still can't seem to figure this out. I had a 45 in it before. I could. It get the idle to go very low. I think it's still too fast with the air screw all the way in. So I switched to a 48 and there is no difference. I mean it seems rideable. Just the idle is a bit high which I hate. It's got me wondering if the throttle cable is messed up. The idle screw does absolutely nothing.

---------- Post added at 06:39 PM ---------- Previous post was at 06:16 PM ----------

I still can't seem to figure this out. I had a 45 in it before. I could. It get the idle to go very low. I think it's still too fast with the air screw all the way in. So I switched to a 48 and there is no difference. I mean it seems rideable. Just the idle is a bit high which I hate. It's got me wondering if the throttle cable is messed up. The idle screw does absolutely nothing.

---------- Post added at 08:32 PM ---------- Previous post was at 06:39 PM ----------

Thanks for all the help. I'm so happy I finally figured it out. After I took the carb apart like 10 times and played with all the adjustments I figured out the throttle cable was zip tied too tight in one spot. Would not come back to idle. Gosh I was so frustrated. Still need to change the idle jet back to 45 I threw a 48 in with no help. Now I know why
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  #22  
Old 10-13-2016, 12:26 AM
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Quote:
Originally Posted by lcgordon711 View Post
I know how confusing this can be.. oil's coming out of the pipe, so you figure there's too much in the gas and decide to put less oil in (higher premix ratio), but no luck. It would only make sense that the less oil you put in the gas, the less comes out of the pipe, right?
I wish it were that easy..
What determines how much oil will come out of the pipe is how hot the conbustion temperature gets. You need a certain amount of heat to burn off the oil. When you run 32:1 premix, you basically have 97% gas and 3% oil. When you run 40:1 premix, you have 97.5 gas and 2.5% oil. So, in 40:1 you have more gas in each charge than in 32:1 - with me so far? OK - now more gas means richer mixture... the mixture is determined by a ratio of gas to air, and oil isn't factored into the equasion. 97.5% gas is more than 97% gas, right? Ok - so now we know that 40:1 ratio is actually richer than 32:1 (Air fuel ratio). The richer the mixture, the cooler the combustion temperature. Believe it or not - gas acts as a coolant in the cylinder! So - by going to less oil (40:1 or higher) then you're actually making the mixture richer, which in turn makes the combustion temperature lower, which means there is not enough heat to burn off the oil.
So what should you do? It sounds to me like you have a jetting problem. Go back to 32:1. Make sure you are running the proper temp plug for your bike, then lean out your jetting a little until the bike runs well, and doesn't drool oil excessively out the pipe.

From another forum. Good bit of info that really explains why more oil makes fuel/air leaner which is what you are jetting for.
glad that now you have understand the real deal.

about the idle, try to use the idle screw to adjust the rpm then use in conjuction the air screw to get the low-mid rpm mixture right, adjusting the air screw also affects the idle speed so you have to adjust little by little both of these two to get proper idle and low rpm air-fuel mixture correct.

about the oil on the pipe, is all about getting proper combustion temperature and you can achieve this only by getting the jetting right (air/fuel mixture throughout the rev range) no matter if you use 32/40/50/60:1 oil mix ratio, leaning the mixture actually raises the running temperature because as you said less fuel/air mix = less cooling through the cylinder + less lubrication (oil). there is a sweet spot for every engine that you've got to figure out and that is the challenge. oil does affects rich-lean mixture but not by much at these % differences such as the jets that are used (bigger jets flow more fuel/oil mix so more oil gets through too) ALL these derivatives have to be set in a good BALANCE depending the engine use you gonna do e.g. desert racing (high engine rpm) go high oil mix and a tad on the rich side, trail riding go lower oil mix (less engine rpm) and a tad on the lean side through out the rpm range.
jetting is a big chapter but once you have understand it and know what you are doing it gets sorted easier.

my 2cent.
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  #23  
Old 10-13-2016, 07:23 AM
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Thanks for the response and info. I could not believe that was the problem. I have worked on the bike for 6hrs the past 2 days and its 2 days before my dad comes. I was starting to freak out.

The good thing is is that I knew a bit before about carbs but now I know way more and when I get some time am actually really excited to do some actual tuning.
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  #24  
Old 03-18-2017, 03:12 PM
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Hi guys im back. Having a weird problem with my bike now. It seemed to go well today for about 30 min and then it seemed like it was starving for gas at mid to high throttle. Couple of issues is I dont know the difference between a rich sound and a lean sound. I thought it was lean but It could have been rich.

I was riding before at about 15 degrees cooler and it seemed a bit rich but still very ride able. I had a little bit of oil coming out of the exhaust but not a ton. Today I had it running all down my pipe and onto the swingarm. I tried changing the plug on the trail and it was black but it was dry black not really wet looking. It was wet kinda on the threads tho. I got back to my house which is 4000 ft elevation difference and it did the same thing. I then changed to a 155 instead of a 158 and seemed to be the same.

I almost feel like maybe its an electrical problem and its cutting out. I dont know thats just a guess. I wish I knew more about a lean/rich bog noise. I just feel with all the oil coming out it would not be too lean.

My specs are 9000k elevation
main 158
needle 1st postion
idle 48( i think)

---------- Post added at 03:12 PM ---------- Previous post was at 02:51 PM ----------

I talked to a mechanic and he said it might be a crank seal. Does anybody know how hard that is to fix and if I need to split the cases?
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  #25  
Old 03-20-2017, 07:51 AM
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Little update, I bought the left and right side crank seals. They were cheap enough I figured I would just do them with out a leak down test. The right one went pretty good except for that I could not get the kickstarter off. I had to go rent a jaw puller from autozone to get it off.

While I am in there I am going to file my clutch basket just slightly. Also am going to change my kickstarter seal because it is leaking. I also have new gaskets on order for the clutch covers and water pump.

I hope this right side seal is my problem. Looking back it makes sense, the bike ran pretty good last year and then this year it started to run just a bit worse. Then this weekend it was ride able for about 20 min then it just went to crap. I was able to make it home but it had no power over 1/2 throttle pretty much. My buddy who rides with me said my bike smokes all the time so that is another reason I would think this is my problem.

I don't think I need to change the left side seal but I figured for 11 dollars I would. But I'm worried I will have to re time the bike after wards. Is that the case or If Nothing moves and I put it all back the same should it still be in time?

Thanks guys
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  #26  
Old 03-20-2017, 10:27 AM
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mark the stator with the cases using a permanent pen so you know how to get it back.
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  #27  
Old 03-20-2017, 10:07 PM
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Thanks for the tip. It sounds pretty simple. Im still not sure if I will do it though. I have alot of other things to get done on the bike. Good thing I have 2 so I can still ride this weekend.
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  #28  
Old 03-26-2017, 06:04 PM
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Ok guys so a little update with bad news. I put it all back together and it still seems to do the same thing. I put in an old plug and and warmed it up with it and it did it. So I changed the plug with a brand new one and it still did it. Im not totattly convinced its a rich issue. If I was going to do my best guess at what it is doing is it has good power bottom and mid and when I go full throttle it almost like I am pressing on the kill switch. The plug really does not look black or wet with 5-7 min of ride time on the bike.

So trying to think of things to check next. I want to do a compression test on it. I rebuilt it two years ago with not much riding on the motor and mostly trail riding. What about the reeds could they cause this issue. What about timing I know two strokes vibrate alot and this is an 03 could something have rattled loose? I am going to take the carb apart and clean it. I under stand the concept of float hight but am a little confused on how to change it and measure it.

I would love to hear from you guys any suggestions. What about cutting the plug wire back just a bit? I know stand up jet skis they recommend this.

I just dont know what to do
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  #29  
Old 03-26-2017, 08:00 PM
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Sorry for being lazy, but it's a long thread and I'm jumping in pretty late. Have you checked the reeds? Had a guy recently describe a very similar situation recently and as we tried to sort through it he found his reeds were cracked.
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  #30  
Old 03-26-2017, 08:41 PM
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Gusco, No problem at all I really appreciate the info and help. That was my next thing to check. I got new fuel lines for my carb so I will have to take the carb off to do that. So I was going to check the reeds when I did that. I hope that is the problem. Just buy the things and it is fixed. Really no labor. I hate chasing problems.
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  #31  
Old 03-27-2017, 08:50 AM
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Does anybody know if aftermarket petals will go on the oem block? Is it a noticeable difference if I put in the v force kit over oem. I see an almost new oem set on ebay for 50 bucks if in fact my reeds are bad I may do that.
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  #32  
Old 03-27-2017, 06:05 PM
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Well Im stumped again. Took the carb off seems to look ok on the inside. Ill Clean it though. I looked at the reeds and they seem fine. They all seem to have the same tension when I pull them back and I cant see any cracks. I took off the exhaust and looked in the cylinder and the piston seems to look good. I just dont understand.

I took the ingnition cover off and Im not sure what Im looking for their. I did notice a little bit of wetish dirt on the bottom in their so not sure if thats the problem. I checked the spark and it seems to be good. Not really sure what it looks like when its bad but it seemed to look blue.

The only thing I can think is somehow my jetting turned wrong with out any changes. Or I have bad gas somehow or it is something electrical. From my limited knowledge of electrical things I think there is 3 electrical parts on a bike. The Cdi, coil and the stator.

I always thought if the cdi went bad it was just bad and the bike would not run. Is this the case?

The other two things are the coil and the stater. What tests do I need to do to check these parts. Does one of these two parts going bad cause my problem.

Also one other thing is timing I dont know what Im doing there either. Any advice on that?

Thanks again guys for the help. I have arrived and waiting at frustration station and hoping to get the next train out of here.
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  #33  
Old 03-27-2017, 09:25 PM
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So question here. I got on youtube and figured out how to test my coil and my stator. I did it to the best of my ability. Here are the numbers from the book.
Primary .17-.46
Secondary 13-20K
mine
Primary .37
Secondary 15.6k

Stator (I dont know what the each of the wire combos do)
R/W-B/R 28-46 mine 46.6
Red-Green 78-122 mine 108

Does this seem like they should be in working condition? They seem good to me. Maybe that one reading is a bit high on the stator?

What do you guys think
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