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New valves, won't kick but will roll start

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Okay, I bought this bike and the guy I got it off of said it was completely rebuilt top and bottom end. I confirmed He had infact rebuilt everything. And it only had 10 hours on it. Bike started getting extremely hard to kick towards the end of last season. And I thought it was valves. I put new kibble whites in over the winter (did them myself) it was my first time and I was eager to learn. That all went fine. I did take it to have them shimmed. After this I had a spark problem. I've literally replaced cdi box, coil stator tps, and put a new wiring harness in it.. I'm getting spark. But it doesn't seem to want to kick over, unless its been running for a minute. My question. I know I'm getting spark and fuel. If the timing is 180 out, would it still be able to roll start? (And seem to run fine) but not be able to kick over? Thanks in advance for your help Snapchat-821552002.jpg

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You mention replacing the valves this winter but were the seats re-cut ?

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Stainless steel or Titanium valves ?

Lapping can be touchy, big no-no on Titanium,

and can wear away the thin coating of other materials.

Edited by mlatour

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Stainless steel. Like I said. The valves were tested all sealed correctly. It seems to run good. It just doesn't Want to kick over unless it's warm

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I've rode it today for a while. It runs great. Will kick over when warm. But once it cools back down again has to be roll started.

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Top checked timing today. Its on the mark. On the clutch side. Also Have the cam lines lined up with the head. But the stator lines are off? Very confused by this as I double and triple checked that I was on the compression stroke. How can the line be off on the stator? If I'm on it on the clutch side?

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The way I understand it the spark goes off both on compression and exhaust strokes so you can't get that wrong.  Only the timing.

So if the stator mark doesn't line up with the gear mark on the clutch side window, maybe that gear just wasn't installed correctly (off a tooth or more on the splines).

 

I haven't seen this where the bike with timing not set quite right would start via kick starter when hot and run good (stable idle, carb settings within expected range), so I'm quite curious what's up.

You didn't touch anything in the carb while working on the bike and you're sure your TPS is set correctly and both carb boots tightened up?  Disconnecting the TPS might be a quick troubleshooting possibility just to eliminate that one.

Edited by dakh

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Yes. And nothing was done other then the valves. No bottom end work or anything. So nothing has been touched. It should run. As it did last fall

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Are you positive your valve clearances are in spec?. The bike I just bought did exactly what you are describing and one of the intake valves had zero clearance. 

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I had a 2007 CRF 250r and had the same issue. Would not kick start but would push start until it warmed up. Thought it was a valve issue but it turned out to be my pilot jet. Replaced it and fire up easily after that. I don't remember jetting sizes but it looks like you have a aftermarket pipe so more than likely the previous owner had it jetted. Check your carb. Hope that helps

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2 hours ago, Tiller_629 said:

Refresh my memory. Valve is
.004 Intake
.011 exhaust?

on an 07:

Intake:  .12mm +-.03mm or .005" +-.001in

Ex:  .28mm  +-.03mm or .011" +-.001in

Edited by TPA-MX

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A few things I can suggest.  

1. Did you put the right spark plug in?  04, 05, 06+ -- there are 3 different spark plugs that for these 3 different model year (ranges).  If you put 06+ spark plug into a bike with 04 CDI it won't run right and have weird fueling problems.

2. What's your starting procedure?  I would guess the bike is lean by your description, did you try whacking the throttle before kicking to see if more fuel would help?  Does it catch at all or is just dead?  

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I've rode a lot the last few days. It runs like a raped ape. Just has to be rolled. But like I said once its warm it will kick over. Sometimes first kick. But not always. I'm going to tear apart tonight or tomorrow and see what I can't figure out.

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If it starts and runs good when warmed up, the only thing I can come up with is somehow the choke is not working.  You don't have to take anything apart to check, just unscrew the whole choke assembly off the carb.  But yea, checking valve clearance seems the next logical step.  

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Valve clearance is spot on. Intake could be a touch lose (as I'm not sure how tight they need to be exactly) but shouldn't be effecting it. I'm almost positive that my timing is off. But I'm not sure how that's possible with the clutch side being on and the stator side being off

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Okay. Pulled the plug. It has an autlite 4302 can anyone tell me If that plug is right for this bike?

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Honda only specs NGK and Denso for those bikes.  I found some cross references but they all seem sketch.  I doubt you can be sure it's the right one.  What year is the bike?

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