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Main Area => General GS500 Discussion => Topic started by: Ron888 on January 08, 2014, 07:24:07 PM

Title: Bolts in the SIDE of the cylinder head?
Post by: Ron888 on January 08, 2014, 07:24:07 PM
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?
Title: Re: Bolts in the SIDE of the cylinder head?
Post by: adidasguy on January 08, 2014, 10:48:42 PM
I have no idea.
They never come out so just paint over them.
Title: Re: Bolts in the SIDE of the cylinder head?
Post by: Big Rich on January 08, 2014, 11:06:42 PM
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.
Title: Re: Bolts in the SIDE of the cylinder head?
Post by: adidasguy on January 08, 2014, 11:19:27 PM
Here ya go.....


[attachment deleted by admin]
Title: Re: Bolts in the SIDE of the cylinder head?
Post by: Big Rich on January 08, 2014, 11:37:22 PM
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.
Title: Re: Bolts in the SIDE of the cylinder head?
Post by: adidasguy on January 08, 2014, 11:41:20 PM
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?

Title: Re: Bolts in the SIDE of the cylinder head?
Post by: Ron888 on January 08, 2014, 11:48:05 PM
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
Title: Re: Bolts in the SIDE of the cylinder head?
Post by: Ron888 on January 08, 2014, 11:50:32 PM
Quote from: adidasguy on January 08, 2014, 11:41:20 PM
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  ;)
Title: Re: Bolts in the SIDE of the cylinder head?
Post by: adidasguy on January 09, 2014, 12:05:28 AM
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.
Title: Re: Bolts in the SIDE of the cylinder head?
Post by: Janx101 on January 09, 2014, 03:35:40 AM
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!!
Title: Re: Bolts in the SIDE of the cylinder head?
Post by: dinkydonuts on January 09, 2014, 11:05:30 AM
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?
Title: Re: Bolts in the SIDE of the cylinder head?
Post by: dgyver on January 09, 2014, 11:13:50 AM
Quote from: dinkydonuts on January 09, 2014, 11:05:30 AM
...

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

No.
Title: Re: Bolts in the SIDE of the cylinder head?
Post by: gsJack on January 09, 2014, 01:21:04 PM
Plugs holes for cross drilling between oil passages.  Leave in place.

(http://www.gs500.net/gallery/data/500/OilPassagesGS.jpg)
Title: Re: Bolts in the SIDE of the cylinder head?
Post by: adidasguy on January 09, 2014, 01:27:02 PM
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!
Title: Re: Bolts in the SIDE of the cylinder head?
Post by: gsJack on January 09, 2014, 01:38:09 PM
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
Title: Re: Bolts in the SIDE of the cylinder head?
Post by: Ron888 on January 12, 2014, 12:48:14 AM
Quote from: gsJack on January 09, 2014, 01:21:04 PM
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!
Title: Re: Bolts in the SIDE of the cylinder head?
Post by: sledge on January 12, 2014, 02:32:02 AM
Quote from: Ron888 on January 12, 2014, 12:48:14 AM
Quote from: gsJack on January 09, 2014, 01:21:04 PM
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  :dunno_black:
Title: Re: Bolts in the SIDE of the cylinder head?
Post by: Ron888 on January 12, 2014, 06:13:46 AM
Quote from: sledge on January 12, 2014, 02:32:02 AM

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  :dunno_black:

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
Title: Re: Bolts in the SIDE of the cylinder head?
Post by: sledge on January 12, 2014, 09:43:11 AM
Tapered pressure plugs.

http://www.socket-allied.com/products_socket_pressure_plugs.asp
Title: Re: Bolts in the SIDE of the cylinder head?
Post by: radodrill on January 12, 2014, 10:57:05 AM
Quote from: Ron888 on January 12, 2014, 12:48:14 AM.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.
Title: Re: Bolts in the SIDE of the cylinder head?
Post by: adidasguy on January 13, 2014, 03:19:23 AM
Quote from: Ron888 on January 12, 2014, 06:13:46 AM
Quote from: sledge on January 12, 2014, 02:32:02 AM

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  :dunno_black:

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
Some motors I have do not have allen bolts there.They are plugged with press in rods that you cannot remove. Case closed. Those are oil passage manufacturing plugs you do not touch.
Title: Re: Bolts in the SIDE of the cylinder head?
Post by: Ron888 on January 13, 2014, 04:06:06 PM
Quote from: radodrill on January 12, 2014, 10:57:05 AM

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

When i bought the bike it ran ok'ish i guess (??).Then after a while i noticed it was changing- it got a big rich spot when the throttle was wound right on. So now i have a smaller main jet and its running well. The weird part is why did it change all by itself?Or maybe i just didnt notice the rich spot at first- i'm sure this isnt the case)?

Anyways,whatever,its good now.Just trying some subtle changes to get it perfect :-). it's hard tho!I was trained on two strokes many years ago.Tuning four strokes isnt so easy! I think i have the main jet perfect now.I might try richening the needles a little and see how it feels
Jeez this is an awesome forum huh?The level of knowledge and the enthusiasm is great :-)