Jump to content

crf250r 2006 Honda CRF250R Starts Sometimes / Doesn't start sometimes / Doesn't idle well sometimes / and more

Recommended Posts

Okay so the title is a little vague. 

So it was having trouble idling and even starting when I first bought it about a month ago for $2k. 

So I did a rough clean of carb, looked up on YouTube, Forums, Etc on how to do it. I only cleaned jets with carb cleaner and sprayed around the float bowl area and such, so not too extensive.

Did that and I took it out to a park, It would start up right away mostly, few kicks sometimes, but when I got it started, I had to keep the choke on. Right when I was ready to go fast and go up to 3rd and 4th gear I'd switch it off and it would work fine and sound fine and everything, but when I slowed back down and coasted around 1st gear i'd pop it back out again because it sounded like it was going to do. I have some videos if people would like me to link to them.

 

So after that I decided to take it apart and replace spark plug with OEM NGK R0409B-8, replace main jet from a old 170 to a new 170, replaced pilot jet from a old 40 to a new 42, and kept starter jet the same just made sure that wasn't clogged, ordered a new adjustable fuel screw and used that.

and it was still having a little bit of problems! I just started up today and the day before today. It would run only with choke on, if i twisted throttle in neutral it sounded pretty good, no gun shot noises or anything, pretty smooth. 

If I tried to take choke off it would die immediately. So I started it back up again, took around 6 kicks.. So again with choke on it sounded like it was starting to lose power and RPM's would drop so I'd twist throttle a few times and it would stay idling.. then after a small amount of time, start to sound like its about to die again... so I would rev it up again, and repeat..

 

Fuel line isn't clogged, flows fine.

I tried fuel screw everywhere between 1 and 2 turns out..

I checked valve clearances, and I'm no expert but from the videos I watched the slipped underneath intake and exhaust with only minor force.

So I'm lost.. 

Maybe float bowl is messed up? Should I just do a COMPLETE carb rebuild from videos I've seen on youtube, like this one -> https://www.youtube.com/watch?v=3AXb9UprT30? Or what? 

 

It's getting annoying taking it apart all the time, I jsut want it to start up quickly and run well!!

 

Thank you!

 

Austin, TX, Elevation 600ft, where I ride its around 900ft

 

 

Edited by Matt Ray

Share this post


Link to post
Share on other sites

From the over all explanation, I’d say you need to look into the pilot jet.  It’s probably clogged or too small.  

The pilot jet will cause a bike to act just like your describing.  However with these high performance 4 strokes there are a million probable issues, but I’d start with your pilot jet

Share this post


Link to post
Share on other sites

Haha I just replaced it with a new 42 pilot jet, stock is supposed to be 40.. I haven't blown air through the pilot jet hole that leads to fuel screw yet.. 

Share this post


Link to post
Share on other sites
On September 24, 2018 at 4:39 PM, Matt Ray said:

Haha I just replaced it with a new 42 pilot jet, stock is supposed to be 40.. I haven't blown air through the pilot jet hole that leads to fuel screw yet.. 

The pilot circuit is clogged then. The fuel goes into the jet then into a myriad of passages, those fuel passages are likely clogged up with old rotten fuel and/or debris. Happens all the time, you just need to better clean out all of the carb's air AND fuel passages and verify flow-through before putting carb back on.

Edited by Eddie8v

Share this post


Link to post
Share on other sites
On 9/29/2018 at 7:37 AM, Eddie8v said:

The pilot circuit is clogged then. The fuel goes into the jet then into a myriad of passages, those fuel passages are likely clogged up with old rotten fuel and/or debris. Happens all the time, you just need to better clean out all of the carb's air AND fuel passages and verify flow-through before putting carb back on.

I honestly think that’s what it is because I have new pilot jet in and it’s clear but I never blew out the passages with compressed air.. lol..

 

is dust cleaner compressed air okay?

Share this post


Link to post
Share on other sites

Did you check to be sure the idle speed (knob) is turned up/in enough to promote a decent idle rpm?

Share this post


Link to post
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:


×