94 yz 250 starting problem

[1BAD250]

hello everyone. i just bought my first 2 stroke 250. its a 94 yz 250 i went threw with my genral mantenance checking everything over toping off fluids & neww gas. so far what i now is the guy said the bike had a new complete rebuild 2 summers ago [ top & bottom ] plus clutch. it has 210 pounds of compression a boyesen rad valve complete pro cercit exhaust & i beleve the air box has been modified cuz there is no lid ween the seat is removed all you see is a twin filter . anyway it seems to be hard starting i notest the reeds had gaps so i fliped them but only one would have no gap but it helped a little but it takes like 20 kicks but once worm it will fire right up but if i let it cool for around 2 hours i start the hole prosses over agin & the kick start lever goes down close to the foot peg & im braking my foot so i have to remove the peg to start it then put it back on when running once started it idles & runs great it runs a bit rich but id rather that it just sucks to have to fool with it to get it running & i hate the kick lever.im vary good with my hands so what ever you guys think i can do i have done a serch but theres nothing new allways the same old stuff that i allready know it has plenty of gas nice wet plug great spark runs great when its running other than it seems to tochy like you barley touch the gas & its there im also thinking its to powerfull for were i ride cuz i still have to lean forward in 5th gear i dont know if i can get used to that. please help

 

[SKIDOOrider800]

quick start may help. I've noticed on my bike that as the cooler weather has set in it has become harder to start. place a space heater beside the engine for 10-15 minutes before your ready to start. when your ready follow your normal start procedure (fuel on, choke on, two hits of throttle, then 16th throttle in and kick it over is should start right up..thats what works for me anyway).


if you do have a gap in your reeds they should be replaced, I believe this can cause hard starting as well.

 

[RocketRaccoon]

after reading your post I noticed that you never mentioned the choke. You are starting it with the choke on?

 

[1BAD250]

yes i use the choke. but if i over do it it soaks the plug then i have to pull it hit it with a bit of flame then thats when it usuly starts. i know that i need a new plug i just cant aford it right now so im switching between 4 plugs i have. so a part of the problem is fouled plugs but ive owend a blaster cr 125 & a kx 80 before & never been like this its allwayes 1 or 2 kicks & the 250 is much more harder to kick over i have to use my body to start it. plus what you guys think about my kick statrter smashing my foot on the peg its like its to shoryt but the guy said it original.

 

[SKIDOOrider800]

there should be a built up spot on the kickstart where it contacts the peg i would presume. maybe a lighter tranny oil would also make it easier for you to kick over. also start it in neutral but also start it with the clutch lever in? (so your not rolling the whole clutch boss against the oil

 

[dogs_bolox]

some bikes will lose compression with the clutch in but others will not.

 

[1BAD250]

ok. about the carb. on the left of the air/fuel screw in the middle there is a screw with a lock nut on the end what is it for when i move it it dont seem to change anything? the kick starter does stop on the peg but were your foot rests on the L part to start it goes just down past it to were your foot goes just under the peg and slams the top of my foot. also are 250s common for the trotle being totchy its like if ya barly touch it its gone i tryed to add a little free play from the top of the carb. but it seems to just ajust the idel also on the trottle cable ther is a ajustment but it does the same only idel. is there a trotle stop screw somwere? i mean its crazy on just a small jump or even just a wleely when i come down if your not carful with you hand it will rev up & almost flip back. i orderd a 15T sprocket hoping it will kill some of the power to be able to shift at full tritle with out the front end coming up now it has 14T / 52 renthal sprockets & chain. i mean my freinds kx 250 was never like this even when he rode it he said damb.its like i cant have fun when im trying not to wipe out.

 

[1BAD250]

thanks for your replys guys.when i bought the bike the guy said that he only road it maby twice a year & im starting to beleve it cuz it seems the more i ride it the easier it starts

 

[splatt]

I have a 94 and the kick start lever is a foot breaker. I won't even give it a full kick anymore. I just kick straight down so the bottom of my foot lands on the peg. As far as your starting problems go get a new plug or two for starters and then you'll probably have to play with your jetting. Once you have that all sorted out you'll have probably the most brutal 250's Yamaha ever made.

Steve

 

[scottyh770]

ya i agree with splatt,my bike wont even run off pump gas and if i try all it does is foul plugs and not run,ive been told by alot of people that rejetting your carb can fix them kinda problems,it can depend on what gas you run and what the owner before you had it set up to fun,i need to jet mine all i can start the bike off is cam 2"5.40 a gallon"wich kinda sucks

 

[rosscopeeko]

I would also get a replacment set of boyesen reeds for your rad valve and swap them out. I had the same bike back in the day and i loved it. Your air filter is not modified. All bikes are missing the top area for removal when cleaning. Hope i understood you right. Anyways, as mentioned before get a new plug, play with the jetting, keep the air filter clean all the time, same with the tranny oil, get those new reeds, use high octane fuel and a consistent pre mix ration. Also, 250 2 strokes are all touchy on the throttle. You'll get used to it with time.

 

[1BAD250]

yea iv been using the same plug it been starting easyer. im going to tear the carb. apart agin & check all the jets & holes & give it a complete cleaning.im going to get new reeds but havent decided witch ones i want yet black carbon or the same ones in it right now fiber glass single peddle .[what you think] i weight around 190 6' tall my sprockets are 15T 52T rear i pre mix 10 oz oil 2 one gallons 93 octane it smokes a little when idel to half but hardly none at [ w.o.t ] my air fuel screw is 2 turns out.i still have a problem with the trottle thow its so tutchy & the kick start lever man i dont know i need somthing longer

 

[RocketRaccoon]

yea iv been using the same plug it been starting easyer. im going to tear the carb. apart agin & check all the jets & holes & give it a complete cleaning.im going to get new reeds but havent decided witch ones i want yet black carbon or the same ones in it right now fiber glass single peddle .[what you think] i weight around 190 6' tall my sprockets are 15T 52T rear i pre mix 10 oz oil 2 one gallons 93 octane it smokes a little when idel to half but hardly none at [ w.o.t ] my air fuel screw is 2 turns out.i still have a problem with the trottle thow its so tutchy & the kick start lever man i dont know i need somthing longer

:yikes: How much oil do you use?!?! What ratio are you mixing at? At 32:1 you should be doing 4oz. oil to 1 gallon gas. If you are mixing 10oz. per gallon...better get a few cases of plugs. You are going to need them.

 

[1BAD250]

woops i ment 10 oz to 2 gallons around 28:1 the guy i bought it from said he only road it 2 to 3 times a year so im being carefull.

 

[rosscopeeko]

If it was me i would go with the black carbon pro reeds to replace on your rad valve. I don't remember my kickstarter being a bitch either, but i bought the bike used and it may have had a kickstarter off of a 94 wr250. That gearing you're riding must be extra tall. I run a 13 front 51 rear on my cr and it's a little low for the fast trails. It was way to fast in first stock gearing at 13 48. You might want to keep an eye out for a flywheel weight too, that might tame it a bit. My 94 had a long rod kit installed in it, flywheel weight, fmf pipe and silencer, rad valve. Felt very smooth for power. I'm light too at 5'7" 160lbs. Anyways, keep tinkering and you'll figure it out.

 

[1BAD250]

well when i first got it the gearing was 14T 52T it seemed to low probubly went 65 to 70mph but couldent seem to keep the front wheel down but now im getting the hang of holding my body weight forward. as far as mods iv notest the full pro cercit platnum exhaust polished,rad valve, carb. spacer, aluminum renthal bars & sprockets & chain,track buster tires,i think my front triple trees & forks are aftermarket cuz there gold colored not like ive seen on other bike being crome, theb guy i got it from said it was standard bore weisco pro-lite piston kit & he said somthing about a aftermarket power valve but i cant check that, & full set of ceet grpfics package id like to put pics on here but dont know how.The 2 stroke oil i use is the same i used in my blaster full senthetic mobil 1 mx oil, as for transmission oil iv allways used rotella 15w30 it has no friction modifiers its about $8.00 a gallon you can get it at any auto parts store its good stuff i use it in all my engines it realy stands up to the heat. i cant wait till i get my manual there is still a screw on the carb. that i dont know what it is its right to the left of the air/fuel screw its like the air screw but it has a lock nut maybe i have a diffrent carb. it says TM MIKUNI its got like a big trap door on the inside not a piston i was thinking of checking my needle clip setting iv just been busy.

 

[2strokerfun]

ok. i orderd a 15T sprocket hoping it will kill some of the power to be able to shift at full tritle with out the front end coming up now it has 14T / 52 renthal sprockets & chain.

And you can't afford a new spark plug ????????

 

[KX250Dad]

Virtually no one, and I mean no one, not even Ricky, Bubba or Chad have a need to run a 250 2stk balls out (at least not often). Why do you think 250 2stks run right with the 450F's Should you have checked the compression correctly and it's 210psi your basically new, if you had reed issues it would show up in compression loss and bogging low end. Should the bike have the throttle response you describe the reeds are OK so save your money for now. In so far as starting, at 210psi you should have a 1 kick bike. When you use the choke don't ever apply any throttle until the choke is down, throttle and choke = foulded plug especially at 28:1 In so far as the kick, you'll learn to position your boot back and outward a bit further this will become a natural thing. When all else fails go back to factory jetting, jetting's and art form all in its own, jet wrong you crash/trash the bike. The "snap" of a two stroke is what 2-stoke guy's want, it's what will give you an edge on some of the 4F's. To tone it down you can broden the band via sprockets 14-48, use 8oz flywheel weights, or distance the head from the cylinder a few 0.000" I might suggest while your going thru this new 250 learning curve you move up a gear prior a jump this will help keep the front down and help when barking the throttle when you land or go thru whoooops. Take it from a fellow 250 rider with metal in his shoulder, its better to slow down to become fast than to be fast between emergency room visits.

 

[1BAD250]

im starting to figer it out. i did some tread serches & learned no throttle works great.i was thinking of a flywheel weight & need to go threw the clutch it still drags even when worm so im thinking the clutch basket is notched im just going to do little by little threw the winter plus i sure hope i get used to that kick starter its tearing my foot up.il let you guys know how it turns out as i keep going threw stuff it sucks i cant tune the carb. till wormer weather. oh well.