1993 kx250 cold start help

[scobydo_kevin]

hi, i am new to the boards and have also just baught a bike. i baught a 1993 kx250, and it has all the bells and whistles. well, i am posting because i am having trouble getting it started when it is cold. once i get it started initially, it starts easy. i have heard that the reeds and other stuff may have an effect on starting it, so i will tell all you guys what i have on it. ok here it goes, it has fmf gold series pipe, fmf turbine tip, new top end(about 8 hours on it), boyesen reed rad valve, jt sprocket, new fork seals, new suspension, desert riding tank, pro taper bars, and uni filter air filter. i know a few of thoes have nothing to do with the starting problem, but i just decided to list them any way incase people wanted to know what i had on it. so, like i said, it is hard to start in the cold, and i always hear about people that can start their bikes in the cold in one or two kicks when it takes me around 30 if not more. so please, if any one knows a way to help, please let me know.

Kevin :)

 

[Matt90GT]

blah blah blah what you have on the bike. It is a 93 bike.

How much compression does the motor have?
Have you inspected the power valves and governor?
Taken out the reeds and inspected?
What is the jetting on the bike?
What plug are you running?
What mix ratio are you running?

 

[scobydo_kevin]

173 psi compression
have not checked valves, dont no how
reeds are brand new, maybe 2 months old
no clue how to check jetting
ngk 9 plug
42:1 mix
i think the jetting is fine, cause once started it runs fine and restarts fine, and i have no clue how to tell if the valves are messed up.

 

[KXtrailrider]

If everything is OK with your bike and your having trouble maybe it's you. Try pulling the enrichner up DON'T touch the throttle and kick, sometimes people crack the throttle without knowing it. This is what mine takes when it is cold. Good luck. Ed

 

[Matt90GT]

Well the older kawis are known for having power valves freeze up especially if you use cheap oil. if you have one stuck or broken that can cause some issues.

I would suggest to do some searching on the jetting. Then open up the carb bowl and see what you have in there. at least clean the carb jets with air

 

[CRazy250]

its most likly a dirty carb. or dirty air filter. bikes always start right up after they have been run because they have air/fuel mixture in the engine.

 

[scobydo_kevin]

i dont believe it is a dirty carb, soely because before i posted the tread, i cleaned the carb, i will check the air filter, but do you really think the air filter would stop it from starting but not from running? and how do i find out if the valves are frozen? and how do i fix it? but wouldnt a frozen valve keep it from running at all not just starting it up? and could it be the mix has to much oil so when it is cold it cant start it and burn the extra oil?

 

[Matt90GT]

Well having worked as a mechanic for a while I have seen what some people call "clean" carbs and they are not.

The power valves are on a governor and operate at a certain RPM. Take off the pipe, the side cover on the cylinder and the cover on the top from and move all the parts by hand. Other than that, you take off the top end, remove all the parts, clean inspect and replace what you need. The early kawis do have issues there if not maintained. but they will not stop the motor from running, just really hamper the power.

I was thinking that your jetting is probably the biggest issue. Running 40:1 means you are running more gas and less oil. The stock jetting is setup for like 32:1. Thus you are rich. I remember my 91 kawi 250, I had to lean the jetting and then even more when I was running 50:1. Again do some web searches for the jetting on the bike. Check sites like FMF, bills and pro circuit just to get an idea what jetting they have posted there (if they have it that old still). Tear open the carb find out what main, pilot and clip setting you are on. Remove the air screw make sure all the passages are clean. Inspect the bell and blow through all those passages. Also install a new plug.

 

[scobydo_kevin]

ok, i will do that, and while i am at it, if i need to change the clip, what clip should i put it on? 1 am also going to try changing the mix to 32:1. and, i will also try cleaning the carb again, and lastly, i read some where that the aftermarket reeds can have an effect on how a bike starts, is this true?

 

[scobydo_kevin]

i changed out the reeds to the stock ones and that made a big difference, it is alot easier to start now, thanks for all the help.

 

[elcamino12sec]

Try A B8es Plug Instead Of A 9.

 

[Bent6]

I had a few 2-strokes that were hard to start cold, but ran fine once started. The backyard solution? Lay the bike over on its side until gas runs out of the carb vent hoses. Cheap, easy, and works great on cold blooded bikes.

 

[scobydo_kevin]

thanks man, i will try that once i get my rad valve back in.

 

[elcamino12sec]

I have a 1995 kx250 and the stock plug is a b8es, I run a b7es (one step hotter) and it starts 1st or 2nd kick and I never foul a plug. I can run it hard all day in the hot Florida summer and never have any cooling issues ever. It has a fresh diet of 93 octain, 40:1 Redline 2t oil and stock jets, starts and runs great all day.

 

[76GMC1500]

Normally, when you start a 2-stroke, you roll on the throttle a little as you kick it. But, when the bike is cold and you have the choke on, you should not touch the throttle at all. For some reason, when cold, my bike only starts when you kick it gently... Too hard and she throws a fit.

 

[CRazy250]

man ive never had any starting problems with my bikes. kick them ovr once or twice and instant fire.