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new to 2 stroke

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First off hello to everyone. I was fortunate to aquire a 93 RM 250 pretty cheep I've been banging my head trying to figure out a few problems so thought i'd try asking for some help.

so excuse me if i seem a little confused.The guy i bought the bike from had it sitting for about 5 yrs. in his garage. Here is what i have done so far, redone top end since (compression was down to 90 psi) new piston, rings and so on. Cleaned carb which is PJ model after i redone the top end i took it into the dealer to have them rejet and check carb since i was having a hard time starting it well i got it back and still could not kick start it my leg would go numb from trying now when the bike is running it runs great on the top end but on the bottom it seems to sputter and bog down till i get into third gear it seems to me but like i said first 2 stroke (always worked on Harley's) that something is not right with the carb. I live in Las Vegas,NV and right now i have a 45 pilot 180 main with the needle set on 2 down the air screw which i have adjusted while bike is running is about 1 1/2 turns out. a couple of days ago i realized that no matter how many times i kicked it it would not start even using the choke ( pull plug its dry so not flooding it out) which is what the dealer kept telling me i was doing or fouling out the plug. By chance i poured a little premix down the top of the carb and low and behold bike started on 2nd kick run it for awhile but when i shut it down for lets say 3 minutes or more it will not start again checked reed valves and yes the were curled since dealer didn't have a set they told me to turn them over which i did has not done anything to change the way it starts or should say don't start have changed plugs going to a hotter plug and opened gap to going back to stock plug. So here i am finally :thumbsup: at the end of what i think might be wrong with it and looking for some suggestions as to what to try next. Sure would like to get out and :ride:

Thanks all

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Definately sounds like a problem with a carb or a spark plug. First, get the stock plug, and start jetting from there assuming that your air filter is clean and oiled. Use the jetting tips and charts at the Suzuki 2 Stroke FAQ section. If that does not help, your problem could be in electrical. Check how strong the spark is and test all electrical as per your manual.

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Time out, what dirt bikes have you owned up to this point? The reason that I'm asking is that dirt bikes do require a certain "technique" to start, you do not just "kick and go" a 250 or a 500, sometimes not even a 125.

Also, as far as the air screw being 1½ turns out, that seems excessive. Most require them to only be about ¾ of a turn out. If it's too far out then you are actually letting too much air in and not enough fuel and that could be problem #1 (remember it's an air screw, not a fuel screw).

As to starting the bike there are some tricks that might help. First off, instead of pouring fuel down the carb, just turn on the gas, pull the choke and then lean the bike over to one side until fuel spills out of one of the carb over flow tubes (a 5 second deal), then stand it back up and kick. This works just like dumping fuel down the carb only it's quicker and you do not have to actually touch the gas.

And as far as kicking it goes, lever posistion and quickness is what starts a 250 2 stroke. When you kick it through you will notice that it's "soft" for most of the lever travel, but it will get into a section where it's hard - soft - hard. You want to slowly kick through until you get in the middle of the two hard spots, then posistion the kicker as high it you can get it, then in one quick and smooth motion ~ kick the starter all the way through it's travel.

So re-adjust your air screw, lay it over long enough to flood out, then get between the hard spots, and in one fluid motion kick it all the way through.

Your bike should be running after 3 to 5 kicks when it's cold.

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ok well i'm willing to try anything at this point as far as the air screw everything i have been reading says to warm bike up then adjust air screw turning untill highest RPM's about 1 1/2 turns from bottom. also the guy told me to do almost what you said about kicking it over said turn on gas pull choke up kick thru 2-3 times then when i feel the resistance on the kicker let it raise all the way up and kick thru i've done that countless times untill i'm outta breath pull the plug and its still dry like it has not gotten any fuel. i could understand it if the plug fouled from flooding it if that were the case. I have checked the stator and coil with OHM meter and manual and all reading are within spec's so i will try leaning the bike over and try that to see if it works something has to????

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Oh and by the way this is the first dirt bike i have owned But did own an old 75 sportster that was kick start so talk about a bear to start

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if you are kicking it that much and you are sure you got gas to the carb you are sucking air somewhere. my 2000 rm 250 only takes about 5-6 kicks to start. unless its real cold?? if thats the case try warming your garage..

real cold =below 35-40 f

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Thanks willybslow but i don't think its the cold cause weather out here in vegas has been in the low to upper 60s. I guess i will have to pull carb again and this time see if i can find out what size needle i have in it that and get the number off carb and see if it really belongs on my bike cause if i think back when i first took it apart it had a 45 pilot and a 320 or 360 main and from what i have found on some jetting guides thats about right for an RMX carb don't know if that would have worked now ya see why i'm going a little nuts. I went to FMF's website and found the jetting guide they have so thought i would try what they have listed and see if that works any better than what i have

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Ummm, put your air screw back to ¾ turns out and leave it alone. It would be worth checking the jetting ~ you never know. Did the bike come from your area? What I mean is, you didn't buy a bike that was normally ridden in the mountains and your at sea level?

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I think Zig06 might be on to something.

I had a 79 shovelhead (kick only) a 66 triumph (kick only) and my rm250.

There is DEFINATELY a different technique to starting the 2-stroke.

You'll get used to it.....

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As said above, did you check and see how the spark looks, maybe a coil or something. But definitely sounds fat when its running.

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Ok guys i think i finally got it pulled the carb again and found it does have a stock needle so went back to ground zero stock pilot(45) jet stock(180) main jet, stock spark plug, and played around with that figured if i was having to put gas into it to start it ment it wasn't getting enough (sucked into it to start) so changed pilot to a bigger 50 kicked it and checked plug soaking wet, backed that down to a 48 pilot and kicked 3 times and it started whooopie even shut it off waited about 10 min and on 3rd kick started again warmed it up and adjusted air screw it's now about 1 1/4 turns out from bottom was dark out so could not take it out for a ride but going to do that today need to run down and grab a couple main jets (178 and i guess the next one higher than 180 ) some new plugs and check WOT. Think i'm finally understanding this jetting thing,since pilot seems ok and when i get the WOT done i guess if i have any kind of bog in the middle i would adjust the needle up or down one step right ? I want to say thanks to all that have given me ideas on what to try. I'll let ya know how its running later on again thanks to all

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well didn't get to do the WOT but did ride it a little bit around the house and i can tell i'm getting close now it's got to be the needle or main jet bike starts offin 1st gear great but when i get in between a 1/4 an 1/2 throttle it sounds like its got a governer on it shift to 2nd same thing also in third rev's a little bit then goes flat when i hit 4th i can open it up and it rev's out. so i'm kinda thinking maybe the clip is now 3rd down from top if i move it up 1 and try that see what changes if not then i'll play with the main jet go up 1 size then down one size from where i'm at now after i get this figured out maybe i'll try lacing a wheel for the first time

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yeah your so right on the dealer sticking it to me first they tell me i don't know how or i'm fouling out the plug then tell me everythings is right all that for around $200.00 well lets see after that i found out the reeds were curled so had to flip them around then go up one size on the pilot jet ran better but seemed like it was governed so played with the needle first moved it down one, it was on the 3rd from the top ran worse so moved it to the second down from top and finally got to take it out today runs great just got home pulled plug and its a nice tan color couldn't ask for better so after paying for it once then redoing the work myself i finally got it running right. Thanks again guys for all the input on ideas to check now to go out and have some fun

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yeah your so right on the dealer sticking it to me first they tell me i don't know how or i'm fouling out the plug then tell me everythings is right all that for around $200.00 well lets see after that i found out the reeds were curled so had to flip them around then go up one size on the pilot jet ran better but seemed like it was governed so played with the needle first moved it down one, it was on the 3rd from the top ran worse so moved it to the second down from top and finally got to take it out today runs great just got home pulled plug and its a nice tan color couldn't ask for better so after paying for it once then redoing the work myself i finally got it running right. Thanks again guys for all the input on ideas to check now to go out and have some fun

I personally HATE dealers. I even have several friends who have had top ends done (2-stroke and 4-stroke) and the shop didn't even put in the circlip rings. :banana: Dealers are especially over priced pay having an hourly wage of $85! So for right they can :lol:! :banana:

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