Bolts in the SIDE of the cylinder head?

[Ron888]

Hi Guys!
Just a quickie question. Does anyone know what the purpose of the allen bolts in the sides of the cylinder head? I have a workshop manual but it doesnt even mention them in any of the disassembly procedures.

Can i temporarily take them out to clean/paint them?

[adidasguy]

I have no idea.
They never come out so just paint over them.

[Big Rich]

Just curious: which allen bolts? I'm having a hard time picturing where they are...... If they are what I'm thinking of, there are similar bolts on late 70's / early 80's GS bikes that were used for something like top end oiler kits...... Although, I could be completely wrong.

[adidasguy]

Here ya go.....


[attachment deleted by admin]

[Big Rich]

Thanks Adidas. If you do a Google image search for "Suzuki GS top end oiler ", there are some examples of what I'm thinking of. I'm sure Suzuki put those bolts on a GS500 for some other reason though, but I've never heard of them being taken out for anything else.

[adidasguy]

Possibly plugging up holes made when machining the oil passages?
If anyone has a junk head, take them out and see what they go to?

[Ron888]

The main reason i want to take them out is to clean them properly (bench grinder with brush etc)
They have ugly rust patches which make the rest of the motor look bad.

BTW,thanks heaps for your quick replies guys!I've new here so good to see such enthusiasm

[Ron888]

Possibly plugging up holes made when machining the oil passages?
If anyone has a junk head, take them out and see what they go to?

Yeah,that's the most likely purpose for them. I'm guessing it might be fine to pull them out but best to be sure in case it throws something completely out of whack 

[adidasguy]

We NEVER take them out so please DON'T DO IT!

If anyone of us ever took them out, we might know what they are for.

[Janx101]

Unless someone says it's for 'xyz' ... I would agree with blocking holes.... The bike equivalent of welsh plugs in a car engine? ... But because of the small size an Allen head bolt/plug was better? ...  And more aesthetically pleasing!!

[dinkydonuts]

I've got some spare cylinder heads at home. I'll take them out tonight and let you guys know.

Just a guess, but, aren't they used to retain the valves or valve springs?

[dgyver]

...

Just a guess, but, aren't they used to retain the valves or valve springs?

No.

[gsJack]

Plugs holes for cross drilling between oil passages.  Leave in place.

[adidasguy]

I was just now looking at pictures of a head, location of oil passages and came to the same conclusion: where the horizontal passages were drilled out.
Good diagram!

[gsJack]

Found these a long time ago, they've been handy at times.

http://www.gs500.net/gallery/data/500/medium/GS500_engine_1.jpg

http://www.gs500.net/gallery/data/500/GS500_engine_2.jpg

[Ron888]

Plugs holes for cross drilling between oil passages.  Leave in place

Wow great pic!! Thanks

Actually that tells me it should be safe to remove them temporarily.

I'll let you all know how it goes.For now i'm tied up in getting the main jets right.Man it's a major operation just to make each change!

[sledge]

Plugs holes for cross drilling between oil passages.  Leave in place

Wow great pic!! Thanks

Actually that tells me it should be safe to remove them temporarily.

Steel plugs in alloy??

Have you read some of the posts from people who have had problems with seized header bolts and the difficulties they have had?

I suspect they will be tapered plugs and depend on being very tight to make the seal. They are not intended to be removed, if they were they would be shown on the parts drawings and have a part number

Its your bike and your call but if there is corrosion there and the threads strip or pull out with the plugs.........you will be in a world of pain all on your own 

[Ron888]

Steel plugs in alloy??

Have you read some of the posts from people who have had problems with seized header bolts and the difficulties they have had?

I suspect they will be tapered plugs and depend on being very tight to make the seal. They are not intended to be removed, if they were they would be shown on the parts drawings and have a part number

Its your bike and your call but if there is corrosion there and the threads strip or pull out with the plugs.........you will be in a world of pain all on your own 

Hmmm interesting thoughts.I suspect they are simple grubscrew sized bolts with tapered contact surface to hold the pressure in.No big deal i think.However i will consider this for a bit

[sledge]

Tapered pressure plugs.

http://www.socket-allied.com/products_socket_pressure_plugs.asp

[radodrill]

.For now i'm tied up in getting the main jets right.Man it's a major operation just to make each change!

True but worth it in the end; the difference between stock jets and best main jet is night and day.