WHAT is this hole for?

I was wondering if anyone knew what the little hole on the side of the head is right above the exhaust header? I only ask because I notice some oil had weeped out of that hole and I don't know if its normal.

Here is a pic I took before I washed the bike. You can see the oil leak is very slight. The owners manual says nothing about it.

img00049h.jpg

Thanks, KC

I think in my owners manual says its where coolant can weep from it. from time to time I wouldnt worry about it unless its constantly running out my buddy has a klx 650 and his leaks from time to time make sure coolant level is topped up and all other fluids are good and ride it like you stole it

.....already....

It's a drain for water or whatever gets into the spark plug tube past the boot.

Nice thread title by the way:lol:

Is it not something for the air pump on the US models???

+1 on the title and +2 on the drain hole. My XT has the same - it's there so that water which/wich/witch - sorry I'm not altogether awake - runs into the spark plug hole can seep out. Is it oil leaking out there, or possibly just dirty water?

I think its oil because its stained into the casting.

Its a drain for the spark plug hole.. If theres oil weeping out of that hole, id suggest you remove the spark plug and inspect if its sealing correctly.. Once you pull it apart you will understand how the hole works.. its also a good idea before pulling the plug to blow some air with an air gun into the hole with the spark lead removed, this blows any dirt from around the spark plug, so when u pull the plug the dirt dosent get into the engine..

Hope i made sense...

I think in my owners manual says its where coolant can weep from it. from time to time I wouldnt worry about it unless its constantly running out my buddy has a klx 650 and his leaks from time to time make sure coolant level is topped up and all other fluids are good and ride it like you stole it

You have no idea what your talking about, the waterpump and the head are 2 very different components...

Its a drain for the spark plug hole.. If theres oil weeping out of that hole, id suggest you remove the spark plug and inspect if its sealing correctly.. Once you pull it apart you will understand how the hole works.. its also a good idea before pulling the plug to blow some air with an air gun into the hole with the spark lead removed, this blows any dirt from around the spark plug, so when u pull the plug the dirt dosent get into the engine..

Hope i made sense...

Spark plug you say:thinking:

I should have checked it today while I had the seat and tank off.:p

Ok.... who gave me bad gas for this post?????

Spark plug you say:thinking:

I should have checked it today while I had the seat and tank off.:p

:lol::cry::lol: :lol: :lol:

If you have a little bit of oil leaking there nothing to worry about, the tube is pressed into the head and must have a very small leak from the oil in the top of the head.If it gets alot worse you may need to have the tube replaced,but I would wait until its time to do the valves and you will be in there already.:p

Most Japanese bikes, especially inline engines, have that same hole for each spark plug. As others have said, it's a drain if water gets past the spark plug boot.

I have seen oil come out of it before but it was my fault. When I tore down the top end on a GSXR at tech inspection at Bonneville and put the head back on, there were square o-rings that go between the valve cover and head that seal the spark plug tunnel. One of those square o-rings moved on me. Then oil came out of that drain hole on a 200 mph backup pass. I pulled off the track at the end of the run and had smoke pouring out from the fairings.

Pull the valve cover off and check it. Sometimes those seals will also compression set or harden and no longer be effective. It's a slight leak now. You don't want it to get worse when you're 20 miles from the truck.

Thats what she said?

Thats what she said?

Yep. That's why I don't talk to her anymore.:p

Most Japanese bikes, especially inline engines, have that same hole for each spark plug. As others have said, it's a drain if water gets past the spark plug boot.

I have seen oil come out of it before but it was my fault. When I tore down the top end on a GSXR at tech inspection at Bonneville and put the head back on, there were square o-rings that go between the valve cover and head that seal the spark plug tunnel. One of those square o-rings moved on me. Then oil came out of that drain hole on a 200 mph backup pass. I pulled off the track at the end of the run and had smoke pouring out from the fairings.

200mph on what bike with what mods?

Spark plug you say:thinking:

I should have checked it today while I had the seat and tank off.:p

Ok.... who gave me bad gas for this post?????

why would someone give me bad gas for this post??????

200mph on what bike with what mods?

GSXR 1000. Buncha mods and custom stuff. Record stands at 219 in the 1000 MPS-G class.

:p... if anything leaks from that hole, plug it with your finger until you get back to the truck. :cry:

Sorry, I couldn't resist. :lol:

I was wondering if anyone knew what the little hole on the side of the head is right above the exhaust header? I only ask because I notice some oil had weeped out of that hole and I don't know if its normal.

Here is a pic I took before I washed the bike. You can see the oil leak is very slight. The owners manual says nothing about it.

img00049h.jpg

Thanks, KC

:smirk:It's a relief port, it's there in case you over pressurize your cylinder.:excuseme:

Edited by CRF450XNUT
because

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