is this exhaust ports healthy?

[ozgurakman]

Hi, I just pulled my bike's manifold and looked it's inside. The #2 cyl's exhaust was black than I inspected the valves with a lamp.

I'm waiting your opinions...

Also can I change valve oil seals without taking apart the head like in this video:
https://www.youtube.com/watch?v=n_9Y8Y2vEXw

 

[Naked Stella]

I don't know much about this topic, but I would say that all that build up is bad.

 

[ozgurakman]

any thoughts? Should I change valve oil seals?

 

[TownsendsFJR1300]

At the very least the valve seals are leaking. Hopefully the valve guides are not worn too.

Right now, if you knock that build up off, you'll feel a difference in how the engine run's. I'd be curious to see big that chunk of carbon is too (once knocked off)...

I had the exact same issue on a KLR 250 but the build up was much worse. A bridge I crossed daily (when I was working) I could cross easily and accelerate in top gear W/O incident. With the build up, I had to downshift one gear to get across.

I'm not sure if there's a short cut for replacing the seals with the head on the block.

Some engines, you can pressurize the cylinder thru the spark plug hole with an air compressor.

Remove the spring retainer and the spring. Air keeps the valve up/closed. I suppose you can push the valve down a tad and measure the back and forth play, that its within spec's. If so R&R the seal, re-assemble.

Might be easier to R&R the head and just have a valve job done...I believe you can pull the head with the engine in the frame..


Just looked at the video, pretty slick little tool. I've used the rope trick on 2 strokes (to keep the engine from turning over if removing a flywheel, etc- works good)

In any case, you do still need to knock any excess carbon build up in the ports..

 

[ozgurakman]

hi Scott, thank you for your fine explanation. Now I'm enlightened. I'll change the seals then.

Cleaning the carbon buildup, is it essential? I can go with 142 mph, bike pulls pretty fine IMO. And, should I change the intake ports' oil seals or ex sides are enough?

 

[BlackAndBlue]

If you're going to bother changing the seals, may as well just drop it off at a machine shop and let them do a good cleaning and decking on it, and grind the valves while they're at it. head rebuilds really aren't that expensive usually, and it comes out super clean all around. in my experience it would run you around $300-400. And if you are not experiencing any output problems at the time, it won't hurt to wait. Most any engine that I take apart with any significant miles on it has some amount of oil leaking past the valve stems. If it's not enough to make the bike smoke or lose a notable amount of oil such that it needs topping off, no emergency.

 

[FinalImpact]

Just leave it be as nothing is wrong! If you decelerate this engine from 10k its going to pull some oil. Who cares! Is it smoking or consuming oil? If no, then leave it be.

Rev it more, run the best quality gas you can afford and the increased velocity will clean the ports.