2000 RM250 questions...

[ckassen]

I am new to the whole 2-stroke thing. I know nothing about carbs or jetting. I just purchased this 00 RM250 and have some questions about how the bike should run. All that I know for sure is that the bike has a stock pipe, boysen reeds, a keihin carb, and that my spark plug is as black as can be. I dont know alot about the history of the bike except that I am pretty sure that it WAS raced and then they decided to put the stock pipe back on it when it was sold, so I am thinking that they had it jetted for an aftermarket one, but not sure. Anyways, I have changed the oil in the crank and stuff but what should I do next? It seems to drive OK....but like in the low rpm's it seems to cut out alot, what would be causing this, and what should I check and/or clean? What oil/fuel ratio should I use, what octane fuel, and what brand of oil? I am not big on the whole "buy the best, highest priced stuff out there"....I just want something that wont hurt it....
Thanks
John

 

[whenfoxforks-ruled]

You seriously need a manual,that was one of the few years rm I liked!

 

[Mavrick70004]

when you say black as can be do you mean the color is black or there is actually still oil on the plug when you pull it out and that is causing it to be black?

 

[Mavrick70004]

as for the ratio run 32:1 or 40:1 100 Octane works fine for me, say your cruisin around in 1st or second gear if you completly open it up what happens does it sputter, die, fling you off the bike as it hauls ass down the road?

 

[mox69]

1.) I would personally run 91+ octane pump gas. You probably don't need racing gas, unless there has been motor work done.

2.) Brand of oil is purely a opinion. Amsoil has never treated me wrong, but is a bit spendy. I would goto my local motorcycle shop and ask them, they will point you in the right direction.

3.) For mixture, do whatever the new manual you are going to buy says :). If you don't have one yet, 32:1 or 40:1 works fine. Again opinions vary on this.

4.) If that were my bike I would start by getting a new spark plug, new air filter and cleaning the carb out. Once that was done I would run it again and go from there. If it still was off, I would rejet the carb.


All of these things are explained in the shop manual, which again I very much recommend you buy.

 

[ckassen]

Yeah, the plug has some oil/gas on it; well on the threads.

On the air filter, should I just get a stock Suzuki one or a twin air?

I have been running 91 octane with just a conventional 2-stroke oil and then a good 10w-40 oil in the crankcase.

Ok, in 2nd gear when I am running down the road, I hammer it, it will sputter and kinda bog down and then it will hit the powerband and haul ass. The throttle response just isnt very crisp.

I have been looking for a manual, where is the best place to get one, e-bay?

Also, what kind of rear tire? I need a hard terrain tire, but what are the downsides?

I think that I am going to get a Pro Circuit Factory Sound silencer, but what about the head pipe, the FMF SST?????? Or should I stick to Pro Circuit? I just want to have a fast......not drag bike but.......you know......It just pisses me off when I get beat by a RM125, although it is highly modified... :yell:

Thanks,
John

 

[ckassen]

Oh, I was reading on a different thread and he said that the engine was spitting oil....Anyways, after 2 maybe 3 hrs of riding my rear fender will be covered in oil, and if I am wearing a white shirt then you can see little spots of oil on it as well. I also believe that my bike has been recently rebuilt just because their appears to be all new gaskets in the engine.

 

[whenfoxforks-ruled]

I prefer the oem manuals,clymer will do.You need tools,a compression and leakdown kit.You could have a bad right crankseal.Once you are certain there are no mechanical issues then its time to learn!http://dirtrider.net/forums3/showthread.php?t=48348 http://dirtrider.net/forums3/showthread.php?t=92818

 

[mox69]

A highly modified 125 will not be faster than a properly tuned stock 250. If your 125 buddies are going faster than you, your bike is not in optimal condition, or they are just more experienced riders than you.


Learn how to do the maintenance things and spend some time poking around this forum.


I can guarantee you if you do nothing but put a new pipe and silencer on you will be disappointed.

A lot more throttle response and HP can be found by getting the bike back to optimal condition. That includes performing maintenance and checking for problems.

Again, put in a new spark plug and air filter. Clean the carburetor. Take the reeds out and visually inspect them. After that you might want to try a compression and leakdown test. If those check out ok, you will want to re jet the carburetor.


Stock filter is fine. Personally I am a fan o the "ready filters." $9.99 a piece and pre-oiled.

 

[ckassen]

That really helps alot. Thanks, I dont think that there is anyway that they are better riders than me, but then again we were just going in a strait line, on pavement. Their bikes are tuned perfectly and have just been rebuilt, and one of them is a stroker motor???...idk...I could get into some specifics but it doesnt matter....

The plug is close to new, and the air filter will be replaced soon but doesnt really look that dirty or should I say old.

On the Compression and leakdown test, what exactly is that and how can I do it? Well I know what a compression test is but what would I need to take one or would it be easier to simply have it done?

What is a sign of bad or worn reeds? Would I just be able to tell or is there something to look for?

When taking apart a carb, what should I NOT do? I just dont want to mess anything up. I have taken carbs apart on older and smaller 2-strokes, but this keihin carb looks a little more complex. Also, the screw on the carb next to the choke, what does this control, I was messing with it and it seemed to change the idle, but I know that this isnt the idle control. I just dont want to screw anything up, I have blown up one crotch rocket engine and that was expensive, not including how much of a pain it was to change.

Thanks,
John

 

[Jeromeo]

I think that may be your pilot air screw you are playing with. YOu need to get a manual my friend and also do what mox69 has told you.

 

[whenfoxforks-ruled]

The 00 I had would run like crap,until I put the correct plug in it,and at that price you had better not foul it! All your answers are in the manual,other than the special plug,adjusting the exhaust valve preload was crucial,I am pretty sure that carb has an adjustable choke,powerjet and tps. As I said before,you really need a manual!

 

[2-Strokes 4-ever]

Establish an oil you want to run, and pick your ratio. 32:1 is safe. For woods riding, I keep things simple.......I do 3oz oil to 1gal of fuel (like, 42:1?) You will find many sources that will help you dial in your jets. The thing is, don't mess with changing the oil brand or ratio during or after you find the jetting combo that works.

 

[ckassen]

Yeah, I have been running a 32:1 ratio, with 91 octane fuel. Does the brand of 2-stroke oil really matter?

 

[dmdee99]

First thing you need to do buddy is get a manual. Then I woudl do exactly what mox69 suggested.

"Put in a new spark plug and air filter. Clean the carburetor. Take the reeds out and visually inspect them. After that you might want to try a compression and leakdown test. If those check out ok, you will want to re jet the carburetor"

On top of all the other stuff that mox69 said to do I would also check the silencer packing.

I have the exact same year rm250 as you and I run 40:1 mix ratio. I use 91 octane pump gas and I run Redline premix oil. I have been doing that since I go the bike and have not had any problems.

Hope that helps out.
On

 

[ckassen]

Thanks, I was messing with my pilot screw and noticed that it was set to all the way rich and the idle control was all of the way down. I messed with that for a while and it seems to be running alot better, at least in lower to midrange, still to rich all of the way around but now I have alot more midrange power.

Should I just have the carb cleaned when I rejet it or????? Also, i have heard alot about the packing in the silencer, what exactly does that control, or do, besides keeping it quiet?

Also, how would I perform a leakdown test? Or will the manual explain that to me?

I have ordered a manual and it should be in early next week.

Now that I messed with the carb, I can pull the front wheel off the ground as high as I want in 4th with a slight pull on the front end, and I can pull the front wheel off the ground in 5th but must try my hardest.

Before I messed with anything I couldnt pull it up in 4th unless I tried to jerk the handlebars off. It is still running too rich but I think I am making some progress.

Thanks,
John

 

[dmdee99]

As far as the packing in the silencer goes, I had a buddy with a cr250 that had problems with his bike bogging when he was in the midrange and in the top end. We cleaned his carb and tuned it but it was still suffering slight power loss and bogging. We then just for kicks changed the packing in his silencer and that fixed it.

I read somewhere on this web site when I did a search that it is recommended to change your packing in your silencer 1 to 2 times a year depending on how oftern you ride. This is especially true if you are running a two stroke because the packing will get cloged with spooge (burnt out oil and gas).

The search function is your best friend on this website till you get the manual for you bike.

 

[_JOE_]

Yeah, the plug has some oil/gas on it; well on the threads.

On the air filter, should I just get a stock Suzuki one or a twin air?

I have been running 91 octane with just a conventional 2-stroke oil and then a good 10w-40 oil in the crankcase.

Ok, in 2nd gear when I am running down the road, I hammer it, it will sputter and kinda bog down and then it will hit the powerband and haul ass. The throttle response just isnt very crisp.

I have been looking for a manual, where is the best place to get one, e-bay?

Also, what kind of rear tire? I need a hard terrain tire, but what are the downsides?

I think that I am going to get a Pro Circuit Factory Sound silencer, but what about the head pipe, the FMF SST?????? Or should I stick to Pro Circuit? I just want to have a fast......not drag bike but.......you know......It just pisses me off when I get beat by a RM125, although it is highly modified... :yell:

Thanks,
John

I suggest getting a forestry service approved spark arrestor silencer that actually QUIETS the bike down. Just my 2 cents.

 

[sick 96 250]

you need to pull the carb apart and look at the jetting and let us know where you are. I think you should be around the 152-155 on the main, and somewhere in the upper 40's-low 50's on the pilot but cant remember that for sure. I just know the main is pretty close to what I said. And def get some better pre-mix oil for that thing. I had to use crappy 2t oil from a gas station once just to ride home and my bike did not like it one bit.

Yamalube is fairly priced at around $29 a gallon, but if you can find it, see if you can get Mobile 1 2T racing oil. You use to be able to get it at any autozone but I didn't see it for a while there until I moved out to AZ and they have it again. Seems to burn real clean with RM's compared to other oils I have used with these bikes.

 

[MAUIGROM23]

Slow Down Dude

Ok, you really need a manual. I have a 00 KX 250, which is very similar to your bike. When I bought it, it had blown fork seals, blown rings, and a burnt up clutch. (Race bike. :-) Being a mechanic I bought the manual and fixed it up. (The bike only cost me 700 bucks, and being my first bike I wanted to learn as much as I could about the way they worked.)

A 20 dollar manual saved me at least 1800 bucks.

Nothing is more important than having a good manual.

I have been to more schools than I care to remember and have logged more hours in the engine rooms of more ships than I can remember. Every time I take a tool to an engine I have the manual open right there in front of me. That's what will keep you from screwing up your bike.

Once it's dialed, 250s GET IT. You yank back on that throttle and she will leave any 125 on the planet in the dust behind you. She keeps up with the 450's on the track and in the desert, but in the dunes their found wanting as well. The only thing that I've found that can keep up with me in the dunes are the 500's, but that is a completely different animal. :cool:

Good luck and take care,
MAUIGROM

 

[ckassen]

As I said before, I have ordered a manual, it should be in very soon....

I will get back to you guys with the size of jets.

Thanks,
John