2010 YZ 450 Oil Leak!

[vette747]

Help Needed: 2010 YZ 450 Oil Leak!

I found oil on my right boot last evening after riding. I looked at the bike and found that it was leaking oil from an small hole in the cylinder head. See pic. Any one can tell me what could be the problem?

I have only 12.9 hours on it. I made oil and filter change after brake-in and every 3 hours.

I know that 2009 has similar hole.

Bike was still running great and oil level was ok.

I have been riding YZ 250 2 stroke for the last 10 years. Wanted to make the switch when the 450 would be injection. But I was not expecting problem that fast...

Anyway, if someone could tell me more, that would really be appreciated.

 

[jsantapau]

that hole looks extremely familiar with 2004 wr450and my old 98 400, it is a drain hole for the spark plug well. oil leaking out that hole is not your problem, oil filling up the spark plug well is, my guess would be the valve cover gasket, atleast for what I owned.

 

[vette747]

that hole looks extremely familiar with 2004 wr450and my old 98 400, it is a drain hole for the spark plug well. oil leaking out that hole is not your problem, oil filling up the spark plug well is, my guess would be the valve cover gasket, atleast for what I owned.

Thanks a lot Sir. Your the man!

After I saw your post, I went in the garage. Removed the tank and found that the spark plug cap was kind of greasy when I removed it. I also saw a little bit of oil at the bottom on the well, if I can call it this way. I made sure the spark plug was properly tightened. Then I put some windshield washer in the hole. The blue stuff came right out of the (not mystery anymore) hole. I saw that the head gasket had a flat spot. I removed the head cover and found the damaged seal around the spark plug hole.

You can see flat spot and slotted gasket in the bottom view. It looks like the seal is not round. Like the bottom and the left of the seal are going to crack also.

Thanks again. I went from an expensive time consuming fix to a quick head gasket replacement. In addition, I may be able ride next weekend unless the gasket is BO.

 

[jsantapau]

Roger DeCoster is the man! I don't deserve the moniker "sir" except from my kids, but I am glad I was able to point you in the right direction. just be careful, calling it a head gasket probably will get you the wrong part

 

[Matt90GT]

that is a valve cover gasket and if you put it on the cover first before installing it on the head, you may be able to save it if it is not torn.

if you leave it on the head more often than not it will not line up correctly with the valve cover.

 

[vette747]

that is a valve cover gasket and if you put it on the cover first before installing it on the head, you may be able to save it if it is not torn.

if you leave it on the head more often than not it will not line up correctly with the valve cover.

Thanks, Yes valve cover gasket. There is an half a inch slit in it. I ordered two. In case it fails again in the next 12 hours as previous one did. lol. I will get them tomorrow.

New question: After I removed the valve cover, I found some gray residue. Anyone knows what silicone or glue Yamaha uses? For sure I can use the same high temp silicone I use when I reinstall the valve cover on my corvettes, but if there is anything special Yamaha uses, I would prefer using the same product.

 

[Rich Rohrich]

New question: After I removed the valve cover, I found some gray residue. Anyone knows what silicone or glue Yamaha uses? For sure I can use the same high temp silicone I use when I reinstall the valve cover on my corvettes, but if there is anything special Yamaha uses, I would prefer using the same product.

That's Three Bond Liquid Gasket 1194. Lots of people remember it as Yamabond. All the Japanese OEMs use it. It's available at any bike shop.

 

[vette747]

Thanks a lot. I called my local bike shop and they have the Three Bond 1194 in stock. :cool:

 

[_JOE_]

How do you like the bike?

 

[vette747]

How do you like the bike?

I love it. This is my first 4 stroke. I can only compare to my 2005 YZ 250 two stroke. I have been riding indoor only with the 450. This is winter here, but we have an 80,000 square feet track.

My first reaction is the cornering. It is much easier to turn than my other bikes. It is easier to lean in the corner. The 450 is also easier to pivot in corners. I was looking at the pro-riders taking some line I had hard time to take with the two strokes. Following these lines is natural with the 450. The suspension is still stock but I find it pretty good. I will have it done in the spring. It has more traction in the speed bump. There is no breaking bump on the track, so I could not really compare. Suspension is smooth but is not bottoming out easily. I’m only 135 lbs though. Suspension was very stiff for the first 4 hours.

I do not feel extra weight. I do not get tired faster. This is actually the opposite. No need to shift and clutch all the time. It is also easier to handle in the air. Friends told me that my wips have more amplitude than with my two strokes.

The engine is much stronger than my 250. There is a 70 feet double I had to take in 3rd gear in my 250 and I can just take it in 2nd gear on my 450. There is an other 60 feet table I had to take full throttle in 2nd gear on my 250 and I can now take it mid throttle in second gear even if I do not take the previous corner fast. I just need to open the throttle. A lot of torque, I was expecting more top end, but I will play with the power tuner when I can ride outside. I was expecting more engine brake (compression) before the turn but it just goes fine. Never stalled it in a corner; (knocks on wood).

Vibration is also reduced a lot. The two strokes vibrate a lot. Like a weed eater. The 450 is much comfortable. I feel like on my garden tractor.

It starts very well. I need to put the piston at the top every time thought. I made a test: I had it on the trailer on the highway at 5 degree F for 1 hour and it started on the second kick start as soon I got the bike of the trailer.

There are 2 extra holes in the triple clamps to adjust the handle bar for tall riders. Not several position as my Bud triple clamp on the 250 but could be useful for your riding style.

The boots does not get stuck in the shroud. The bike feels slimmer. Some folks complain about intake noise. I do not.

The graphs in the user guide are too small. All languages were mixed up in the 2005 manual. They are now separated in the 2010 guide, but the graphs are too small and we loose accuracy.

I have not taken my lap times yet, but guys I ride with told me I was already faster.

What I do not like, change the oil every 3 hours. Air filter becomes dirty quite fast (75 minutes ride). And remember, this is indoor only. I’m not in the sand yet.
Air filter takes longer to change. In addition to the seat, we need to remove 2 of the 4 bolt tank and hold the tank up with a special tool (Cable) that comes with the bike and remove a panel. I took some pics and created a page on my web site if you want to see:


http://pages.videotron.com/vette747/ Scroll down to Motocross picture link at the bottom of the main page and click on the **New** 2010 YZF 450 link.

That’s about what comes to my mind. I’m not expert enough to comment about frame rigidity or flexibility.


My two 2005 YZ 250 are for sale. I do not want to ride them any more….

note: Sorry for the vocabulary mistake. English is not my first language.

 

[Rich Rohrich]

note: Sorry for the vocabulary mistake. English is not my first language.

You communicate your thoughts very well in English, much better than some members who were born and educated in the states. :cool: