250f starting (or lack of)

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#1
If I let my 250f sit for more than a couple of days, I have to push start the bike to start it the day before I go ride. So, if I am racing at REM on Sat, I can be found running down the street pushing my bike Friday night! After bump starting it Friday night, I don't tend to have any problems on Sat. However, I still have to bump start it at least once on Sat.

I am unsure of adjustments to the carb that I can make that will remedy this problem. The carb on this bike is quite cantankerous, and I would be hating life if I messed it up more.

I have this problem with the stock pipe, Dr. D pipe, and the Big Gun pipe. My current jetting is stk main, one step richer pilot, and stk needle/clip. The air screw is 1 3/4 turns out. And to make things even more interesting, it is definately time to replace the rings. On that note: I know a hard-strating two-stroke can be the result of worn rings. Is the same true for a 4-stroke?
 
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#3
starting

I put clean air filter on every time I ride. I try the hot start when it won't start as well.

The one thing that did help, was that I after washing the bike, I replaced the air filter and started the bike up. Then before I tride starting it a week later, I ran through the stoke about ten time using the compression release before giving it a good kick. It started on the second kick. But I still ended up having to bump start the thing 3 times the next day at the races!

I have a friend who is having the same problem.

I'm thinking that there is an adjustment to the carb I can make. I just am not sure what it is, or what direction to go. But for some reason, I feel that this is not the first time this questions has been posted here. :)
 
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#4
The direction Okie was going is the logical starting point. Determining if it's too rich or too lean to start will go a long way towards finding a resolution to your problem.

Yes worn rings can contribute to the problem.
 
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#5
too lean/ too rich

Once I can't the bike started by kicking, I have tried pulling the hot start button out, choke on, choke off, you name it. And yes, it always has a fresh air filter on it.

If this helps- After riding for any period of time, I do not have exhaust residue inside the cap of my muffler. As well, it does not have that too lean "pop" when I ride.
 
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#6
Rich has mentioned before that some people have a tendency of over-oiling the filter, causing a rich condition... possibility?

It's funny, the first ride on my F, the fuel screw fell out. Stuffed a perfectly sized stick in it to finish the ride. Yamaha has the part on back order, a month later, the part still isn't here, the stick still is :)

The bike starts with no more than 5-10 kicks when completely cold (sitting for days), and starts 1st kick EVERY TIME during a ride. Sunday was the exception, it was over 100 degrees, needed to crack open the remote hot start for it to run.

I'm not sure I want the fuel screw :)
 
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#7
Van down by the river

nice location, as long as it isn't the Trinity or the LA river.......

I've tried that, I mean giving it a squirt before I start kickin away. Doesn't seem to help too much. I actua;;y set my idle a little above what is recommended, just so' s I don't stall it as much.

I'm still thinking that there is some type of jet adjustment that would help me start the bike easier. That's what I'm looking for, as long as it exists....:)
 

BadgerMan

Mi. Trail Riders
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#8
Originally posted by Rich Rohrich
The direction Okie was going is the logical starting point. Determining if it's too rich or too lean to start will go a long way towards finding a resolution to your problem.

Yes worn rings can contribute to the problem.
Rich,

Worn rings are not the issue here since they get replaced, along with the piston, every five hours!;)

Thump,

Make sure that the fresh filter you keep speaking of sets over night before you install it and kick that high compression engine over.
 
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#9
My F starts fine with no choke after about 10 kicks cold..... 2 kicks hot
stock jets but it is also 90 degrees outside and humid as hell.
 
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#10
It sounds like there IS a carb adjustment in order, but if you cant tell wich way to turn the screw its 50 50. If it dose not start with no choke, no, throttle, with the hot start on, it sounds lean. So try it with Choke on, and try bliping the throttle once or twice. One of these methods shold help the starting. Once you determine wich one is the key you can adjust the carb.
When you push start it, do you have to give it throttle before it startes or dose it start with no throttle?
 

sfc crash

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#11
wow! i feel lucky, my wr426 has only about 60 miles of tight woods riding on it, but always is "willing" to start. cold..2 blips of throttle, hot start out, and last time 3 kicks. if hot, hot start out, 1 to 2 kicks. and after having/kicking a 78 xl250s and litterally kicking and never getting the thing started " it had good days and bad" i feel like this wr is a piece of cake. knock on wood.
 
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#12
My 250F starts first or second kick, hot or cold. No kidding! When cold, I crack the throttle twice, pull the choke, then kick it to life. When hot, I just kick it. I never even need the hot start unless I crash it. There's got to be some kind of jetting adjustment behind starting. I'm completely stock, and I haven't touched the carb.
 

bassfool

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#13
Do you have a spare air filter? if you are using a freshly oiled one each time, it could be part of your problem also. If you have a spare, let the oil dry for a time before you install it, I have a friend that had that problem. If there is too much oil, creates a rich condition, and will not start at all.
 
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#14
air filter

I usually prep my bikes on Thurs for racing on Sat. So they do get to sit for one full day. As well, I use the Silkolene air filter oil, which when it is applied has the consistency of about water, however, it does become tacky when exposed to air.

But if this wher the case, I think that it would become richer as the filter became dirtier during my race day?

But I'm willing to try about anything.
 

BadgerMan

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#15
I have been warned that if you over oil the filter or install it prior to letting the solvents in the oil evaporate, filter oil can get sucked into the carb and some of the smaller passages (circuits) can get clogged which will make starting nearly impossible.