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Matt04
Pro-Am
221 Posts |
 Posted - 02/07/2010 : 11:47:35 AM
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I got a CRF 250 r 2005 model. I have been having a really hard time getting this bike to start. I know that the cold wheather has something to do with it, but I wouldnt think it suppose to be like this
I resently adjusted the valves I set the intake at 7-8 and the exhaust at about 4-6. Could the valves still be to tight causeing some of this?
Also I checked the fireing to make sure that it's getting good fire. First I replaced the spark plug, then a tried to ground it out on the frame while kicking it to see if it fires. Well..... it didn't everytime. Sometimes (very few) it would get one spark. So then I tried with just a screw driver stuck in the spark plung wire to make sure that I was getting fire to the plug. Same results as when I had the plug in. Are these bike suppose to fire while grounding out it the frame?
So then I thought well just maybe it could be the ignition box (I guess thats what its called, the box that plugs to the spark plug). So a buddy had one that we knew was good. I put it on there and it had no change in results. Then I unplugged the CDI box to inspect the wires (all was good there) and when I plugged it back in I had the spark plug laid up on the frame and it sparked when I plugged the CDI box in. So...... could it be the CDI box?
THIS THING IS DRIVING ME NUTS!
Oh... by the way it starts when you pull it off!
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CGray256
Pro-Am
185 Posts |
Posted - 02/07/2010 : 4:17:54 PM
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if it starts and runs when you pull start it it isn't going to be an electrical problem, have you tried adjusting the fuel mixture? I had a similar problem with mine but it was a combination of fuel mixture and tight valves, i had just adjusted the valves in the bike probably 2 rides before mine started doing that and i haven't rode it since. My engine is completely torn down at the moment and my suspicion was right, tight valves again, but this time the intake valves were just hammered.
It may not be the case for you but the honda 250's are natorious for Ti valves getting tight and wearing out due to the stock seats being so hard and beating the valves to death quickly, the only way to exspand the life of the Ti valve is to has Berillium or Bronze seats installed or switch to SS valves. There is alot of talk about power loss with switching to SS valves but unless you ride AMA you won't notice any difference really. This is just my $.02. Hope you can jet your problem sorted out quickly. BTW, there is also a great how to article on Thumpertalk about trimming the decompression lever in the cyl. head to ease hard starting on the 250's. |
Midway Cycle www.midwaycycle.com
09 KTM 250XC-W woods weapon
08 CR-F250R fer da dirt (for sale)
If you haven't crashed you ain't ridin hard enough! |
Edited by - CGray256 on 02/07/2010 4:30:35 PM |
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Matt04
Pro-Am
221 Posts |
Posted - 02/07/2010 : 4:44:33 PM
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Thanks. I'm glad to know that it not a eletrical problem, as that can get expensive. I was thinking a going down there tonight and checking the valves and losing up the exhaust valves some.
Where should I set the fuel screw? I always heard that a starting point is, screw it alway in and turn it 1-1/2 rounds out, then adjust from there. Is that correct?
Also what you think exhaust valves and intake valves should be set on? |
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CGray256
Pro-Am
185 Posts |
Posted - 02/07/2010 : 6:23:09 PM
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i will have to check the the clearance for the valves, i have an 08 and im not sure if there is a difference in it and your 05. i don't have a manual, i always look all my stuff up on my Autodata at work. I will try to find out for you in a few minutes and post back up.
About the fuel screw, you want to run it all the way in and run it out 1 1/2 turns and start from there, 2 turns might be good for as cold as it is outside but it is something you have to adjust accordingly. |
Midway Cycle www.midwaycycle.com
09 KTM 250XC-W woods weapon
08 CR-F250R fer da dirt (for sale)
If you haven't crashed you ain't ridin hard enough! |
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Matt04
Pro-Am
221 Posts |
Posted - 02/07/2010 : 7:11:20 PM
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Went down and checked the valves. Intake is 06 and exhaust is .10. I put it all back together and tried to start it. After about 12-15 kicks (in the heated basement) it finaly started. But......when I moved it outside so I could let run for a few min, guess what? Wouldn't hit a lick!!!!
I'm going to go back down therein little while and try it again. Usually when I wait about a hour or so it will hit again. Could I be flooding it while trying to start it? I usually pump it about 4-5 prior to starting. Thats when it'll hit. After that it'll go dead and I'll pump it one more time. If it don't start then, it usually won't hit another lick until you let it set for about a hour or so.
Are these(Honda)bikes REALLY that complicated to start? We have a 08 Kawi that starts in about 3 kicks. |
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Rallendude
Pro
3928 Posts |
Posted - 02/07/2010 : 7:29:26 PM
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Every four-stroke race bike, 250 or 450, will start on just a kick or two if jetted and tuned properly.
Sounds like you found your valves to be .006 intake and .010 exhausts. That is just right. Has the bike sat for over two or three weeks recently? You may need to clean the carb. The ethanol in gas lately is causing a lot of problems with carbs gunking up lately.
If the carb is clean your jetting should be as follows for this time of year. Pilot jet should be 48, main should be about 180-182, and the needle should be adjusted so it doesn't blubber at 1/4 throttle on the stand. Set the fuel screw about 1 1/2 to 1 3/4 out.
You can get away with a 45 pilot but you'll need to run the fuel screw out an additional 1/4 - 1/2 turn. When the weather warms up you'll need to go back to a 45 pilot and 175 main.
Are you running stock exhaust or aftermarket? |
Ricky Allen |
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Matt04
Pro-Am
221 Posts |
Posted - 02/07/2010 : 8:33:38 PM
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Ricky,
It has the stock exhaust on it. Also it has not been setting. Did you see that about the firing? Whats your opinion on that?
In the mean time I'm going down there to check the jets to see what size they are and I'll get back to you |
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Matt04
Pro-Am
221 Posts |
Posted - 02/07/2010 : 8:38:37 PM
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| The main jet is a 170. Not sure about the pilot yet. I guess I need to go up to at least a 180? Think this was my problem? |
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CGray256
Pro-Am
185 Posts |
Posted - 02/07/2010 : 10:25:55 PM
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the main jet won't keep it from starting but like Ricky stated you need to adj. the carb. accordingly for the weather/temp.
Did you push the bike outside while running at try to rev the bike and it died or did you shut it off and then try and re-start it again outside?
I'm scratching my head on this on.... Ricky? your up. |
Midway Cycle www.midwaycycle.com
09 KTM 250XC-W woods weapon
08 CR-F250R fer da dirt (for sale)
If you haven't crashed you ain't ridin hard enough! |
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Matt04
Pro-Am
221 Posts |
Posted - 02/07/2010 : 10:51:49 PM
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I cut it off then tried to re-start it again outside.
Yea, I know what you mean on scratching your head. I've gotten a bald spot on mine. Been dealing with this problem now for about 2 weeks.
I can always tell when this thing is going to start, cause the first couple times you kick it may hit. But if it's not going to start it's like it has no fire, fuel, or anything. When you kick it, it gives no hint of starting. When that happens, you might as well quite and come back later.
I know we have already talked about this, but it really seems this thing is firing when it wants to. But there again, you ask yourself, why does it start sometime, and why will start when you pull it off?
Puzzling Uh??????? |
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CGray256
Pro-Am
185 Posts |
Posted - 02/08/2010 : 12:13:16 AM
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the starting problem may be from overloading the cylinder with raw fuel and the spark not being able to detinate it all or something to that effect.
The last time i rode mine was on Thanksgiving Day, i took it out of the truck and got my gear on and tossed the leg over and tried to start mine and i kicked and kicked and kicked, then i let my friend kick it over about 20 times too and still it would not start so we had to roll it up on the table top and i had to jump it to start it and i don't know what caused it to not want to start by kicking it but it just did wanna, i thought it was tight valves. Saturday me and my mechanic tore my engine down and inspected the head and valves and althought they weren't extremely tight one of the intake valves was hammered more than the other and that is puzzling to me but we are gonna clean the seats up and install all new SS Kibblewhite stuff to prevent that from happening again.
To me the problem you seem to be having sounds like carb. issues to me but i could be wrong, i know that part of my problem starting mine was carb. related and all of that will be sorted out when i re-assemble my bike in a few days.
I think someone needs to write a CRF's for Dummies book or something and let it explain every minut possible problem/solution for these things |
Midway Cycle www.midwaycycle.com
09 KTM 250XC-W woods weapon
08 CR-F250R fer da dirt (for sale)
If you haven't crashed you ain't ridin hard enough! |
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Matt04
Pro-Am
221 Posts |
Posted - 02/08/2010 : 08:23:20 AM
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Yea, I thought about that too. I guess sometime I get a little aggressive with the throttle pumping. However it seems that it's the only way to get the thing to hit. So it's a two edge sword.
Is there anyway to check the firing to see if it's working correctly? Does grounding it out on the frame work? I'm still aggreeing with you on this one. If it starts sometime or when you pull it, it shouldn't be a firing issue, but I guess my mind keeps wanting to go back to that by default I guess. |
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CGray256
Pro-Am
185 Posts |
Posted - 02/08/2010 : 10:21:43 AM
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| have you checked to make sure the bike is timed correctly? i'm not sure how far out it could be before the valves and piston get in a fight but.... I'm just throwing some guess' out. |
Midway Cycle www.midwaycycle.com
09 KTM 250XC-W woods weapon
08 CR-F250R fer da dirt (for sale)
If you haven't crashed you ain't ridin hard enough! |
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Matt04
Pro-Am
221 Posts |
Posted - 02/08/2010 : 12:31:15 PM
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| yea, I checked that out too. Confusing ain't it? |
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Rallendude
Pro
3928 Posts |
Posted - 02/08/2010 : 1:45:28 PM
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What did you find on the jetting?
Electrical problems are pretty rare on these things. In fact, intermittent electrical problems are really rare.
If the bike's got a 170 main I'm betting it is a 42 pilot. Your problem isn't as much a jetting problem as it is an air temperature problem. The smaller the bike size the more susceptible they are to air temperature changes. You can ride a 450 pretty much year round with no carb jetting issues. On a 250f, they get lean when it gets cold out.
Set your carb up the way I suggested above. Roll it outide with temps from 40 to 60 degrees and you should be able to: pull choke, give throttle TWO twists, and kick. The bike should light within about three kicks. More than 6 or 8, twist the throttle ONCE. If that doesn't work, your jetting is still not right.
Once warm, you should be able to just kick it to life.
As for the fire issues you saw, a four-stroke engine only fires once ever other revolution. My guess as to why you saw irratic spark issues was you weren't kicking hard enough and maintaining the contact to the frame. It's best to ground the outer plug electrode to a steel bolt on the engine for good spark but it should work on the frame as well. The engine has to be turning significant speed to spark as well. |
Ricky Allen |
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jholt
Administrator
807 Posts |
Posted - 02/08/2010 : 8:15:35 PM
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i am waiting to hear from him ricky, It sounds like after he came in the shop today that his hot start is stuck. He was going to install a 45 pilot and check the hot start...
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Joel Holt
JMR Power Sports Inc.
256-381-7556
2008 kawi Kx 450f |
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Matt04
Pro-Am
221 Posts |
Posted - 02/08/2010 : 8:41:25 PM
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Here's the latest. Ricky you were right had a 42 in it. As Joel said I went by his shop and got a 45 jet. Installed it and took the hot start apart. When I pulled the hot start out it did look like it was pull in a little. So I worked the cable back and forth while pulling on the brass stopper to assure that it was all the out.
Put it all back together and got ready for a drum roll................. Got on the bike kicked twice and it started!!! Whoooo Hoooooo!!!!!!!!!! I only let run for just a second or two. I let it sit while I went to eat my supper (best one I've had in two wks by the way) then went back down there to try it again. Started kicking and had to pump the throttle about 2-3 times and it hit. After about 8-10 kicks it started. So just a little harder than the first time, but that was what I was expecting anyway.
While I had it started I twisted the throttle about a 1/4 of the way and then quickly reved the bike. It was smooth and no hesitation in it at all. Even though at a 1/4 throttle it was just a little rough when you just held it there. However it did have a very good idle and smooth throttle response from idle to a quick rev.
So....... I think it still may need a little more adjustment due to the rough 1/4 throttle. Think I need to adjust the fuel screw a little now? I got it set at 1-1/2 to 1-3/4 rounds from all the way in? Ricky, I know you said that I need to run that 180 jet and still have the 170 main in it. Could that be part of it?
Either way, I can live with it the way it is now. As long as it continues to start. I guess it's now to the fun stuff of tuning till it's juuuuuuust right. |
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CGray256
Pro-Am
185 Posts |
Posted - 02/08/2010 : 9:23:06 PM
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| a sigh of relief huh!! Glad to hear that was the problem, what exactly was the problem with the hot start, which part of it was sticking, the cable?? |
Midway Cycle www.midwaycycle.com
09 KTM 250XC-W woods weapon
08 CR-F250R fer da dirt (for sale)
If you haven't crashed you ain't ridin hard enough! |
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Matt04
Pro-Am
221 Posts |
Posted - 02/08/2010 : 9:36:53 PM
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| Yea, I think it was the cable. When i removed the hot start it was hard to push. |
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Rallendude
Pro
3928 Posts |
Posted - 02/09/2010 : 10:50:43 AM
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The Hondas are bad for hot-start cables and throttle cables to get rusty inside and start to seize up. The plungers on the FCR carbs will also seize in the carb and if they're not closed all the way this will cause a bad lean condition. Pressure washing makes all this worse.
You've got two possibilities on the 1/4 throttle roughness. It takes a really good ear to hear it but here's the best I can describe it. A lean bike will usually want to miss and pop. A rich bike will blubber like somethings over the exhaust or underwater. Lean will rev really quickly and like I said maybe pop a little. Rich will rev a little slower and seem to clear out when on top.
I recommend you pull the carb slide out and take out the needle. I'm thinking your roughness will be a little lean due to the 170 main and cold temps out. Lower the clip one position on the needle, which will give you slightly more fuel flow at 1/4 - 1/2 throttle.
If your roughness sounds more like a blubber and its a little sluggish, then do exactly the opposite, raise the clip one which lowers the needle into the main jet more.
It sounds like the fuel screw could stand to come out another 1/4 turn. The way to adjust the fuel screw is to start and 1 1/4 turn or so out. The bike will probably pop slightly when decellerating off the gas. Turn it out in 1/4 turn increments until it stops popping. When you've gone to far the bike will hesitate when you whack the throttle at idle.
Glad you got the bike to start easier. I had a 2005 CRF250 that Len Smith still swears is the strongest 250f he ever rode. It was basically stock but jetted just right with a WhiteBros full exhaust on. I ran U4 in it and it didn't matter what the weather was like, one kick and it would light. You had to know the process though. |
Ricky Allen |
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Matt04
Pro-Am
221 Posts |
Posted - 02/09/2010 : 11:31:25 AM
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Ricky,
I've got to go out of town for hte next couple of days. So I guess when I get back if it still starts easy I'll say that part of it is fixed. But it did start really easy last night so feel allot better about it now.
I'll keep you posted on the outcome. As for the 1/4 throttle problem I'm going to adjust that fuel screw and see what happens. |
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mx614
Pro
469 Posts |
Posted - 02/09/2010 : 9:51:14 PM
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Like RALLENDUDE says its cold out and that main is way too lean, I also had a 05 250f and never had a starting problem. Its better for your wallet to be a little rich as opposed to too lean. |
Danny Gardiner |
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Matt04
Pro-Am
221 Posts |
Posted - 02/10/2010 : 10:18:20 PM
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O.K. guys just got in from out of town. Went right to the basement and crawled up on that hard headed 250. Gave a few pumps kicked it about 8-10 time.... she fired right up!
I'm getting more confidence in this bike now. Thanks to all the help from friends on the JMR Forum. Hoewever I sill got to see it for the next few days to be totaly sure that the problem is solved. Yea, I really lost allot of confidence in this bike during the past few weeks. But it's building back up now.
I'm going to check out the needle position tomorrow night and see how that looks. Also get a 180 main in it as well.
When this conversation is over it should be put in a "How to book for CRF 250's" I think it about covers every avenue on valves to carbs. |
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CRF 250 fireing
