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Discussion Starter · #61 ·
I think we're all forgetting that the OP isn't the first owner. How do we know some butcher hasn't had a go at that head?
The only facts I know for sure about the bike are what I have learned in the last 6 months and 200 miles of ownership. The previous owner bought the bike new, according to him. I really have no idea if this engine has been opened up before. I would assume not, though. Without looking at another head, there is no way to know if this one has been "butchered" or not.

In the pics, the exhaust side is the closest.

I finally got the new exhaust valve and seal. I will swing by on Monday and drop the parts off for reassembly. The head bolts are on backorder so I won't have them for another week or so.

Baby steps!
 

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That is quite an odd torquing method on the cylinder head - specifically the loosening of the bolts at step 2, before re-torque +90° turn.
I wonder if you can't find a replacement grade 8 bolt at one of those Ace Hardwares that specializes in fastners. There is one in Tempe that does that, don't know about Glendale.
I'm surprised they are using a "torque to yield" bolt (the normal reason to replace head bolts).
 

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Duh. I just saw the images. Is the issue the head expert talking about, the uneven cut marks where the seats are pressed into the head?
 

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That's nothing, that's just where the cuts were made in the head material for the seats. If it bothers you, you could smooth that out with a dremel. But I wouldn't bother.
The critical factor is the seats themselves.
 

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Discussion Starter · #67 ·
I got the head all done and back. I don't have pics but the work turned out great. Next I need to assemble the head on the bench and check valve clearances before bolting it to the block.

I am still waiting on head bolts. They were on backorder but I should have them early next week.
 

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Discussion Starter · #68 ·
I think this concludes the saga, at least for a while. I got everything all back together and the valves adjusted properly. (though it took me 3 times to get the exhaust valves correct, lol) I won't know how well it runs until I have the engine back in the frame, but before that I need to pull the bottom end all apart to fix the transmission.

I have sure learned a lot about this engine! I also learned how bad these bikes can be beat and still run.
 

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Yeah I don't know what everyone else was smoking, I could clearly hear the cranking was uneven, my FZ09 cranks immediately when cold but when she sits in the sun for a while, she does struggle to start but the cranking is an even gak gak gak gak gak gak gak, not the asyncopated gak gak, , gak gak, , yours was doing.
Sometimes I feel like people that have no idea about any mechanic work come here and post without having a clue of what they are talking about.
Well the results of the compression test are in:

Cylinder 1: 180 psi
Cylinder 3: 170 psi
Cylinder 2: 30 psi - I tested this cylinder twice, just to make sure the reading was correct.

No offence to anyone posting in this thread, but there hasn't been a lot of help on this one. Obviously this is an issue that doesn't happen very often, but every single person who posted after watching both of my videos claimed that my bike "sounded fine" when I insisted that something mechanical was wrong.

I will reiterate what I stated earlier. If your bike truly sounds like mine does when you start it up, and it seems to lack power at low RPM, maybe a compression check is a wise idea.

When I get back from work this afternoon I will hook up the leak down tester and verify where the compression loss is going.
 
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