Spark Plug ??

[Old Okie]

This is my first experience with iridium spark plugs. This plug is from a 2005 CRF450R.

Sorry for the fuzzy photo. Is this plug OK??

Also, does anyone use fuel filters on these bikes???

 

Edited April 16, 2019 by Old Okie

[Augoose]

More can be told by looking at the electrode, but it looks like it is running rich with how dark it appears.
What is the condition of the rubber spark plug cover? There seems to be a lot of dirt around the exposed part of the plug where the socket wrench goes. Maybe someone sprayed the bike off with a pressure washer and dirt got beneath the cap? You don't want any of that crud falling into the head.

The fuel outlet pipe under the tank has a screen in the pickup but they often deteriorate with age. I haven't run a filter on my CRF450r because I keep the tank clean and I screen/filter my fuel as it comes out of the gas can, but I do have an in-line filter on my DRZ. I wouldn't think your fuel demand would exceed the ability of fuel to pass through the filter, but who knows.....

[Old Okie]

The boot was in good condition and was tight in the hole, no one knows how old thatspark plug is or where it hs been. The bike was running well and it started losing power and making a popping sound occasionally so I am looking for the problem.  The tiny electrode on the plug surprised me.  The plug is a little smokey but the bike has been putted around some. I will replace that spark plug and check the valves tomorrow.  I have the official shop manual and the racing manual so I should be able to muddle through this.  Should I continue with the iridium plug??  Thanks for the help.

d

[Augoose]

Yup, stay with the factory plug. The sharp point on the electrode is that way by design. The smaller the point, the stronger the spark and the hotter it runs (iridium handles heat very well) and the smaller the head of the electrode the less voltage is needed to create the spark.

Definitely check the valves and the condition of the carb as well if you think you might have a fuel delivery issue.

Edited April 17, 2019 by Augoose

[Old Okie]

Not sure about the fuel system. The bike started bogging down when throttle was applied. I am doing the easy/simple things before I pull the carbs.  I have a lot of carb experience with CX500 and GL650 Honda bikes so I can probably handle this one.  My first CX500 I bought not running. Everyone told me it is the carbs, they are so hard to get right.  Three carb cleanings later I replaced the ignition module with one from a parts bike and it ran.

[Augoose]

Hard to say what's causing the bogging at this point without getting some other details. Did the bogging come on all of a sudden? Is it intermittent at all? Will it rev up slowly?

[Old Okie]

Not sure about the details. My grandson rides the bike, he brought it in and told me what it was doing and I haven't started it yet. He said it would not start or was hard to start. It has always started easily. I am a pretty good mechanic but I am 81 years old and I do not ride this bike. I try to keep it running for Zane.  I think this started suddenly and is constant. This is the bike with the oil filter installed backwards. I am expecting the worst. More later.

[Shawn_Mc]

Carbs have pretty easy jobs. Id say the majority of "carb problems" are mechanic induced, or are actually ignition problems, like you found out.

[Old Okie]

I think I am in over my head. This bike needs someone with more experience than I have.

I checked the valves, they seemed tight but the bike was running OK before it quit??

When I roll the engine over with the kick starter it makes gurgling sounds inside the engine

and pops through the carb and also makes a click every turn or so????  Any ideas??

I should take this job to the dealer or a competent mechanic??

[highmarker]

valves tight, as in zero, can't get a feeler gauge under it without forcing it ?

clicking noise is just the decompression device, normal.  

Be prepared for sticker shock if you take it to a dealer. Better to find an enthusiast that works out his garage. Ask around in your area section of thumpertalk.

 

[Old Okie]

Yes I know about sticker shock.  Intakes 0 clearance, exhaust .007 or .008.

How can the clearance just change?? Cam shaft was clean with no damage showing.

I am near Oklahoma City, OK, any one in the area??

 

 

[Shawn_Mc]

52 minutes ago, Old Okie said:

Yes I know about sticker shock.  Intakes 0 clearance, exhaust .007 or .008.

How can the clearance just change?? Cam shaft was clean with no damage showing.

I am near Oklahoma City, OK, any one in the area??

 

 

With the intakes at 0 lash, it wont start. The decompressor comes on and with insufficient lash, there isn't enough compression to support ignition.

The valve lash disappears when the hard coating on the Ti valve is worn off. The Ti doesn't stand a chance against the powdered iron seat. (google powdered metal valve seats). The valve face begins to cup out, the valve recedes into the head and the lash goes away. It happens to all of them, regardless of what some people say. Reshim the valves to regain correct lash and it'll run fine.  But look forward to a valve job in the next 20-30 running hours, would be my guess.

[Old Okie]

I have no history on this bike, would this be a good time for a top end rebuild??

 

[Augoose]

I would. If you are going to be in there checking valves, getting down to the piston is not that much more work. Then you are good for the long term.

Edited April 21, 2019 by Augoose

[Shawn_Mc]

Id reshim the valves first. Reason being, you want to eliminate any other issues before you tear the engine down and wonder if you did something wrong when it wont start still.

[Old Okie]

Going to shim the valves on Saturday, my grandson wants to help/watch/hinder???

Do I buy a shim kit, $89.00?? I can buy them at the dealers but 7 or 8 dollars each, seems extreme??

I have 2 shop manuals and some you tube videos, looks pretty easy.

[Augoose]

That's great that your grandson wants to help! I have to drag my 13 y/o outside to work on his own bike....

You can run your measurements and then go to the dealer and pick up two shims for the exact size you need. Many shops will trade the shims you remove for the ones you need.

I opted to purchase a 52 piece kit online for $34.99 so I have them on hand. I have two bikes that run the 9.48mm shims and I'm 40 minutes from the dealer which is only open Tuesday through Saturday so it made sense for me to buy the kit.

It is very easy. Shawn_Mc and several others have put some excellent information on the forum. Remember to cup your fingers or hold a rag beneath the buckets when you lift the assembly up or you will be chasing a rolling shim across the garage floor.

Edited April 24, 2019 by Augoose

[Fenmore]

Or worse, in your engine.

You can find shim calculators online to get the ones you need.  If you're at zero it's easy.  The shims are about $2 each on Rocky MTN. Depends how much time you have and then shipping if that's all your buying.  

I would follow Shawn's advice and do the shims first 

[Evan D]

Agree. Except if the valves are zero they probably are not. Once they touch they can't go negative but probably are in reality. H e will have to put some thinner shim in to get a reading and then do the math.

[Old Okie]

I was wondering how I would do this without a baseline clearance to work with.

I see the light.