Jump to content

04 crf250r hard start and idle


Recommended Posts

Hope there is a crf250r expert available here.  Bought with out a head found a head and checked all clearances intake is set at .006 and exhaust rt side is .010 and left side is .009  The timing marks are dead on.  Pilot jet is 42 main jet is 152 air mix screw is 2 turns out.  when I get it started without choke, if I choke it, it will not start, if riding it, it runs and takes fuel great when I back off it backfires if sitting still the pipe will glow red at, I am going to call it idle but I have to keep giving it fuel to keep it running and it has the backfiring problem, if I let off of the throttle it will die, before I tear it down I would like to here some opinions. any help appreciated

Link to comment
Share on other sites

Hope there is a crf250r expert available here. Bought with out a head found a head and checked all clearances intake is set at .006 and exhaust rt side is .010 and left side is .009 The timing marks are dead on. Pilot jet is 42 main jet is 152 air mix screw is 2 turns out. when I get it started without choke, if I choke it, it will not start, if riding it, it runs and takes fuel great when I back off it backfires if sitting still the pipe will glow red at, I am going to call it idle but I have to keep giving it fuel to keep it running and it has the backfiring problem, if I let off of the throttle it will die, before I tear it down I would like to here some opinions. any help appreciated

What altitude / climate....and also, have you done the CCC mods? (Air box, pipe/arrestor, etc)

Edit: and what does the plug look like (have ya had a chance to do a plug chop?)

Re-edit: just checked my log book, I run the same pilot, but have to use a bigger jet on the other side...250x here...but I'm just a couple hundred over sea level

Edited by bobsled
Link to comment
Share on other sites

Service the carb, before messing with jetting; the most common problem with carbs is neglect, then poor running

Use a brand new pilot jet, and ream the passage above the jet with fishing line and spray cleaner

 

http://i10.photobucket.com/albums/a147/Krannie/RIDING/IMG_1082_zps51e9ad1b.jpg

 

You should have 45p

 

Put in a Remote fuel screw

  • Like 1
Link to comment
Share on other sites

I reshimmed the exhaust side last night and got it to .011 on both sides. put back together got it started rode for a few adjusted and got it to idle better, but letit die and had to roll it off to get back running. is this a hot valve problem. I am going to mess with the jets tonight and see what happens but I still feel there could be some sort of valve problem. please chime in and give any input 

Link to comment
Share on other sites

Ok so here we go cleaned carb last night, installed new jets 45 pilot and 172 main she runs great still hard to start, worst part is when it gets hot and trying to restart. it is better now than it has been still not where I think it should be. Other thing when sitting at idle speed hands off throttle it races up and down what is cause of this.

Link to comment
Share on other sites

Ok so here we go cleaned carb last night, installed new jets 45 pilot and 172 main she runs great still hard to start, worst part is when it gets hot and trying to restart. it is better now than it has been still not where I think it should be. Other thing when sitting at idle speed hands off throttle it races up and down what is cause of this.

 

 

Dude, no one is going to help you if you keep posting ' I cleaned the carb' when we KNOW you did not replace any of the worn parts, or service the hot start, accelerator pump, etc.

 

Good luck.

Link to comment
Share on other sites

I have been through it completely checked acc pump and cleaned it thoroughly but I do not know what to look for as far as worn parts everything just looks clean, only thing it will not come off rev kinda like it is sticking internally but with carb in hand it appears to open and close just like it should

Link to comment
Share on other sites

yes the hole was on the top. What do you mean one half in backwards. I still have a problem with the idle it seems to take four or five seconds to come to idle after throttle closes is this normal or is there something else I can check thanks

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

×
×
  • Create New...