No High RPM????

[gotmonkeys1]

  Is there anybody on this site that lives in the Clermont or Davenport area that knows a 89 suzuki lt250r inside and out? I am sick and tired of going to all the different dealers with this bike and having them tell me i have to replace this or i have to replace that. I have spend hundreds of dollors in the last month trying to get this bike to run right.It will not produce any high rpms. It is like it has a rev limiter on it and it is set at 2,500 rpms. The only thing i have not replaced yet is the cdi unit itself. I know it is not bad becuase i did an ohms test on the hole electical system. I did however replace the stock stator with a 130w ricky stator, stator. The new high voltadge coil should be in on thursday or friday. If the coil dosnt work then i am ready to push this bike off a cliff. If you  have any suggestions on what might be the problem, please call me at 863-268-3210  my name is Bill. And like i said the only thing i have not replaced is the cdi unit.

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[Dr.Dirt]

Try posting this on www.Floridaatv.com too. There are a few people that have/had lt250r's on there too.

[Old_School]

Tell me all that you have done to it mod wise. I had a 92 that would scream. I owned quadracers since 98'. Let me know. -Mark

[gotmonkeys1]

Hey Old School, This is what has been done as far as engine mods go.
I beleive it is an fmf chrome expnion chamber and fmf spark arrestor
new jug with stock bore
stock head
wisco piston and rings(stock bore)
wrist pin and bearing
(hot rod) rod
boysen power reeds
200 main jet, 45 secondary jet
dg needle pin set on second notch from top
uni air filter
ricky stator 130w stator
stock cdi box
on its way is a high energy coil
11 tooth front sprocket
keihin 34mm carb (im pretty sure it is a 34mm)was on it when i got it
running klots 2 cycle oil and 93 octane gas on a 32:1 ratio
im hoping that it is just a weak spark problem and that the new coil will fix the prob. i have replaced and done everything that people have been telling the problem was. what turned me on to the coil was the manual. i did an ohms test on the components and the coil was only about 3 point above the lowest limit.   hanks for any help you give. This is my 3rd 89 250r. My first 2 never gave me any probs. like this.

[Old_School]

Hey Old School, This is what has been done as far as engine mods go.
I beleive it is an fmf chrome expnion chamber and fmf spark arrestor
new jug with stock bore
stock head
wisco piston and rings(stock bore)
wrist pin and bearing
(hot rod) rod
boysen power reeds
200 main jet, 45 secondary jet
dg needle pin set on second notch from top
uni air filter
ricky stator 130w stator
stock cdi box
on its way is a high energy coil
11 tooth front sprocket
keihin 34mm carb (im pretty sure it is a 34mm)was on it when i got it
running klots 2 cycle oil and 93 octane gas on a 32:1 ratio
im hoping that it is just a weak spark problem and that the new coil will fix the prob. i have replaced and done everything that people have been telling the problem was. what turned me on to the coil was the manual. i did an ohms test on the components and the coil was only about 3 point above the lowest limit.   hanks for any help you give. This is my 3rd 89 250r. My first 2 never gave me any probs. like this.

So low/mid range is fine until you go WOT? If the stator and coil is ok my guess would be the jetting. You have a 200 jet on a 250 cc engine where as I have a 522 and using only a 195 Keihin main. Before you start to mess with the jetting does it smoke alot or load up when riding? Do you have the air box lid on? If so take it off. That will give you more air on the top end. If the lid is already off then try to go leaner on the main like a 195.

What does it do when you goose it? does it start to pull then just die off or is it real sluggish from 3/4 thorttle to wide open? Also where is your power valve set at? -Mark

[gotmonkeys1]

I only get about 1/4 throttle before it starts to break up. When it does start to break up, it smoke like crazy. The air box lid is on. The carb had a 155 main jet in it when i got it. I put the 200 in becuase i was putting the stock settings back to it. The top end was 80 over and sloppy, thats why i started replacing parts. Other than the exhuast, the top end is back to stock. The 200 jet that i put in actually made it run worse. The air screw is set at 2 turns out. I have the exhuast valve return spring set at 180 degrees counterclockwise. The manual calls for 1 full turn, but i want it to open a little faster. When it is at idle and i give it wot, it will snap your head back for about half a second then just start cutting out. One other thing is that the one yamaha tech that i talked to said that the 155 jet was way to small and that i should put at least a 200 in. What gas mix are you using. He also told me that 16:1 was not good either that i should switch it to 32:1. Now the book calls for 20:1. Should i swith it to 20:1?  Thanks Bill

[Old_School]

If it breaks up that low in the rpm it could be timing. Pull the flywheel cover and see if the flywheel nut is tight. My zilla sheared the flywheel key one time and low end was great but would break up in the high rpms. Also pull the carb and make sure the needle is in the middle clip. The a/f screw should be 1 1/2 turns out.  Pull the plug and see what color is it. Being that you don't have any port work and stock bore I'd go down in size on the main and maybe the idle. But if you are too lean your idle will hang for a second then go down. If that does happen go up a jet obviously.  I'd try a 40 idle and a 190 main with the needle in the middle clip and go from there. I have a feeling you will need to go even smaller but start there. Better to run rich to lean than lean to rich.  I ran 32:1 on my 250 w/ Castor 927 oil. Rode trails all day and never fouled a plug. 20:1 is too thick.  My 250 said 20:1 too but it didn't run any hotter with 32:1.  The keihin carb you have is it just a regular one or the PWK, PJ series?

[gotmonkeys1]

The carb is a PJ series. I will give those setting a shot and i will let you know how it goes. Thank you for your help. It is nice to talk to sombody that actually knows what they are talking about.  Bill

[gotmonkeys1]

Well i gave the 190 main,40 idle, and put the clip for the jet pin in the middle and took the air filter cover off and got the same results. I also check the fly wheel and it is set in the right place and the keyway is still intackt. This thing is really begining to burn my hid. The neew coil should be at the house by the time i get home,hopefully. When i get the coil on, i wil post the results.  I am still open for any suggestions.  Thanks Bill

[gotmonkeys1]

   OK, heres another one for ya. Now i dont know why i am asking a yamaha tech(nothing against yamahas) about problems with a suzuki, but here is one of the other things he told me. He said if the crank seals are bad than it is sucking oil into the piston at high rpm. This is a little confusing to me, granted i do not buil atv engines every day, but i do build car engines. The crank needs oil to be lubricated, it dosnt matter what kind of engine it is, there is always going to be oil splashing aroun by the bottom of the piston. If i am wrong, please correct me. i just dont see how a bad crank seal would cuase the problem that i am having. If this i possible, please let me know.

[Old_School]

No prob Bill. The beauty of 2 strokes is that the bottom end is dry.  The crank is lubed by the oil in the fuel. The crank doesn't see any oil that you pour into the clutch cover side. That oil is just for the transmission. You could take the jug off and flip the quad over and no oil will come out. If the crank seals are bad and it's sucking oil into the bottom end it would smoke more than it should and it would smell like your behind a car that didn't have any rings. lol. What's the gap on your plug? I know on my drag car I set the gap at .054" but on 2 stroke quads they are like half of that. I set the gap on my zilla at .024" Pull the plug with it still connected to the plug wire and kick it over. See if you are getting a good spark. Did it run good before you replaced the stator? Maybe the stator is touching the flywheel causing a short? Just a guess. After you tried the jetting and took the airbox lid off and it still did the same thing then it has to be the stator or the cdi box. It's something to do with the ignition and timing. With crank seal blowby it would still allow you to get into the upper rpms.  I'd pull the flywheel off and check the stator and then check the cdi wiring.  We'll get thing fixed. Always good to see another quadracer in the bunch.  -Mark

[gotmonkeys1]

The reason i replaced the stator is becuase of the prob. i am having, I just put it in on wed. The new coils still has not shown up yet. today i gapped the plug to what you said and pulled the fly wheel off and made shure it was not hitting the stator, i also went through all the wiring and made shure there was not breaks or anything in the wires. On thing i did not mention is that there is no light swith or on off switch on this bkie. All the wires are there, just no components. made shure none were touching each other. Then i pulled the air cleaner off and started the bike. Still no change. i know it is not easy to diag. a prob. without seeing are hearing what the bike is doing, but i do realy appreciate all the help you are giving me. After i ran the bike i pulled the pug and inspected.It looks normall, light brown on the electode. I double checked the spark and it seems to be very good, but is it possible that under a load that the coil will not produce enogh spark. that is what i was told and that is why i am replacing the coil. the last peice i would have to replace is the cdi unit itself. And i realy hope it is not the cdi cuase they are not cheap. Thanks again

[gotmonkeys1]

Hey Old School, when i finally get my bike running correctly, id like to invite you and a few of your buddies with bikes to ride in i little special spot that very few people know about. this place is huge and it is only about a 45 min. drive from tampa. There are no fees to ride here and we actually had the sherif dept. back here riding with us. The outter rim of this place took me about 20 mins. to walk around. i have lots of pics. but are to large to post. if you would like some pics i have to email them to you.   Bill

[Old_School]

Bill, sounds great. Let me know. Croom is whooped out and I always up for riding in new spots that won't get my quad impounded. My email address for the pics is bitemark46@tampabay.rr.com    Thanks. Any new news on the quad?  -Mark

[knucklehead]

can I ask a question from either of you since you both have quadracers . I have a 86 250r and I think I need a new crank ( as someone told me ) but I do not really know if I do . How do I check this ? I just put a new sleeve and piston in and in two rides it threw both rings and scored the wall a little and I have no one that can give me any information other then it will cost 600 - 800 to fix . Sorry for jacking the post but I just saw you guy's . Any help would be appeciated mike

[Old_School]

can I ask a question from either of you since you both have quadracers . I have a 86 250r and I think I need a new crank ( as someone told me ) but I do not really know if I do . How do I check this ? I just put a new sleeve and piston in and in two rides it threw both rings and scored the wall a little and I have no one that can give me any information other then it will cost 600 - 800 to fix . Sorry for jacking the post but I just saw you guy's . Any help would be appeciated mike

Sounds like crank walk is what happened. To check you have to pull the jug and piston out. Take the rod and without rotating the crank see if the rod will move up and down. It should have very little play in it. if it has alot of play then your crank bearings need replaced. But if the bearings have been shot for a while they may have worn out the crank. But if you scored the walls that is a good indicator that your crank bearings need to be replaced and that the crank was crab walking (hence the name crank walk).  Is the bottom end still stock? If so, I'd say yes it needs to be rebuilt. On my zilla I have the whole bottom end bearings and seals replaced and even a new rod and it was 632$. I'd say yours should be cheaper.  -Mark

[Quad32x]

One  more  thing.  Untill  you  get  it  to  run  right  reset  the  exaust  valve  back  to  its  stock  setting.  Also  might  want  to  do  a  compression  test  just  to  make  sure  its  not  leaking  anywhere.  Just  my  .02  cents.

[gotmonkeys1]

No, there is no update on the conditon of my quad. Currently i am still waiting on the new coil to show up. i ordered it on the 3rd. hey knucklehead, dont worry about your post man, you got a good guy(oldschool) giving you advice on your problem. god luck with the motor. Hey old school, i will send you the pics to your email.   As soon as i get the new coil, i will post the results.  And quad32, thanks for your insight. even though the top end is not broke in yet, i cuoldnt hurt to make sure.  Thanks

[knucklehead]

hey oldschool I just checked my rod and I cannot move it up and down but I can move side to side about 1"- 11/2 and yes it is stock . I am wondering if the bearing on the crank are pressed on and is this something that i can do in my garage or should I send it out ? thanks again and I would like to ride with you guy's someday if I get this running .

[gotmonkeys1]

Anybody got a bomb!!!!!!!!! I put the new coil on this morning and got the same results.......       I have replaced everything i can replace besides the cdi box, but if i read the manual correctly, if the cdi box was bad there would be no spark at all. Please correct me if i am wrong. I dont know what else to do. Its driving me insane.

[knucklehead]

hey bill I had almost the same problem with no rpm's and mine turned out to be carburation but I did do the whole electrical thing just like you . Best of luck and maybe we can both get them running at the same time with any luck .

[Old_School]

Anybody got a bomb!!!!!!!!! I put the new coil on this morning and got the same results.......       I have replaced everything i can replace besides the cdi box, but if i read the manual correctly, if the cdi box was bad there would be no spark at all. Please correct me if i am wrong. I dont know what else to do. Its driving me insane.

Ok so you got the new coil, you're getting spark, and it's still not getting any rpms? If it's missing at low rpms it's gotta be timing. Lean or rich conditions at low rpms won't miss at such a low rpm. It's just wont' make any power but it should still rev up. Is there a way you can verify what the timing is at? -Mark

[gery350]

no meaning to hijack. but this sickness is going around. my sons z400 is the same. ive changed the carb and the cdi box and now am  waiting for coil.
no high rpm. it doesnt stall but it sputters like crazy.
things ive thought of:
arc jumping to ground from plug boot under load.
petcock valve diaphram busted and sucking fuel through vacuum line.
tearing her down and checking all wires for resistance and ground.
and of course the stuff ive changed/changing.(carb, cdi, coil w/wire)
driving me insane.
i feel your pain.

hey maybe we can put both of them together and get a good running bike or a really screwed up one.

well keep us posted as will i.

[gotmonkeys1]

The timing is set to stock. I alighned the the mark on the stator with the mark on the case behind the flywheel. The carb(keihin-pj), is i possible that it is to much carb for the stock top end. If i am not mistaken, the keihin is a 34mm and the stock carb is a 32mm. The reason i ask is i had on of our master techs. looking at i today and he said that it seems to be way to much carb. for the bike. He said it seems to be running to rich. Do you think i should go down in the main jet size? Oh, by te way, did you get the pics?

[gotmonkeys1]

Well the suspition of the carb being to big was right. i took a chance and out the 155 main jet  back in and i solved most of the problem. It ran great but still had a little bute of break up at top end. So i took the air box lid off and HHHHoooooollllllllyyyyyyy SSSSHHHH@#$#@#$$#@#$ttttttt. The bike just came right alive. No bogging or missing. I just need to make sure i am not running to lean now. i want thank all that posted and gave me suggestion, especially old school. Whith out your help i dont think i would have figured it out. I would have had to take it to a shop and pay an arm and a leg to get it fixed. Old school, let me know when you want to come up and try out my little area. That goes for the rest of you that posted a reply to my cry for help.      Thanks again,   Bill