Idle issues

Recently did a tear down and rebuild of my 95 250. Before bike ran great, idle forever, crisp throttle, pulled to the moon. 

Tear Down Included:

   New Honda Piston/Rings/Gaskets

   Reeds were replaced with Boeyeson Power Reeds before rebuild (maybe a couple hours run time)

   Carb cleaned/ New throttle cable


I didnt change any settings prior to reassembly and now the bike will start 3rd or fourth kick on choke from dead cold. When warmcant be idled, it always seems to high to me and when trying to bring it down, I crack the throttle to clear it and it will come down a bit, shoot up a little and then slowly (maybe 5-10 seconds) die out. Like its bogging out. If you pull the choke on, it will idle fine at what seems like the right speed to me. I am doing this by ear though. It still runs great, pulls awesome and is all around alright until you need it to idle. Bike will always hit on first kick with no choke after being warmed up. Not a huge amount of crap out the tailpipe, but the tip is a black inside. 

 I've tried turning the idle air screw till its fastest idle and then idling down from there, it helped a bit, but it did eventually kill itself. 

The only thing I can think of right now that may have something to do with it is the needle is a little boogered up at the end, not cut or anything, but a little smashed. But this has been like this before the tear down. I've been trying to locate one, but no luck.


Smaller side issue. My front brake is incredibly stiff, it's actually holding pressure on the pads and making it hard to turn the front wheel. I've had the caliper all apart new pads/ and bushings, greased pins. Still pretty tight. Using a mismatch of parts, that may be my issue, 2010 master cylinder(new) and new front brake line, with older caliper. 

Edited by HondaTech

Possibly an air leak. Make a pressure / vacuum tester. Or aim an unlit but running propane torch at all the gasket surfaces.

Sounds as if your caliper is dragging. Often from rust / corrosion on the pistons / bores.

The Boyeson reeds can cause those issues with idle.  Go to thier website and check if there is jetting specs with their reeds.  Generally you have to go up or down a size or two on the pilot jet.  My buddies CR125 gave him fits when he installed Boyeson reeds in his bike until he jetted up 2 sizes on the pilot jet.  I have had other bikes where I didn't have to change a thing.  As far as your brake goes,  you more than likely have air in the system and it needs to be bled and possibly a rebuild on the master cylinder. 

As mentioned above, have a look a the reed installation instruction / guide.


As an example, Boyesen Dual-Stage Power Reeds instructions mention to richen up the pilot jet and to lean down the main jet,

which when installed on my YZ125 was exactly what was required to maintain my previous 'spot-on' jetting adjustments.

Edited by mlatour

Will look at the reeds. Brakes have been bled over and over. My old master cylinder worked fine until I pulled everything apart, then it wouldn't pump any fluid. I bought a brand new,directly from the dealer I work at master cylinder from a 2010 250r. It didn't do this at first, about a week after sitting.

Make sure you didn't over tighten the master cylinder cap.

Pull your pilot and make sure it isn't clogged. Adjust the air screw

when you rebuilt the caliper did you have free movement or was it still stiff?  You might have to replace 2 cylinders ...I'm assuming you put all new seals and stuff in?

Didnt rebuild the pistons, no. But it didnt have the issue until i installed the new master and lines. Maybe the old one wasn't putting enough pressure out to make the caliper stick?

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