Honda-SOHC

SOHC.co.uk Forums => CB650 => Topic started by: Paull on April 04, 2014, 11:56:31 AM

Title: Cylinder Head Bolts
Post by: Paull on April 04, 2014, 11:56:31 AM

Hi All,

Been sometime since I have been here, been building a new monstrosity ;) ;) ;) ;).

Where can i get a new set of cylinder head bolts for a 1979 CB650z.

 Paul

Title: Re: Cylinder Head Bolts
Post by: Bitsa (Ralph Wright - RIP) on April 04, 2014, 07:20:08 PM

Paull,
Dare I ask why?You are a bit vague lost them stripped etc
Cheers
Bitsa

Title: Re: Cylinder Head Bolts
Post by: Trigger on April 04, 2014, 07:30:42 PM

Bitsa, he is most probably going by the book. The manual states that you should change the head bolts if disturbed. Disturbing is the price of them. 

Title: Re: Cylinder Head Bolts
Post by: Bitsa (Ralph Wright - RIP) on April 04, 2014, 07:36:38 PM

Thanks Trig but thats the first I have ever heard off, is it still the 1st of april?I have always said in the past even at my old git age you still can learn.Is that true by the manual?To me as you suggest what a rip off.
Cheers
Bitsa

Title: Re: Cylinder Head Bolts
Post by: Paull on April 06, 2014, 12:44:45 PM

Hi Chaps,

The poor ol girl has had a rough life.

Left in the wet, rebuilt at one time by an animal with no clue.

As an example, the oil gallery plug was put in the wrong way round and a bolt cut off and blue tacked in the hole to push it in.
They used some sort of fencing bolt to bolt the crank case together and snapped a bolt off.

I snapped 4 off getting them out, they were so tight.

I could make studs for it, I have the steel.

But just wanted to know the price of bolts and where to get them.

Thanks for any help

Paul

Title: Re: Cylinder Head Bolts
Post by: Bryanj on April 07, 2014, 06:53:04 AM

The only place you will get those is Honda if they are still available, and they won't be cheap

Title: Re: Cylinder Head Bolts
Post by: Paull on April 07, 2014, 09:48:28 AM

Hi Bryan,

Do you think studding them like a 550 will work?

Personally I don't see it will make much difference. 

All Views welcomed

Paul

Title: Re: Cylinder Head Bolts
Post by: matthewmosse on April 07, 2014, 07:36:38 PM

I have got as far as trial fitting a 650 top end loosely on a 500 bottem end and it looks like it might work so I think that could be viable.

Title: Re: Cylinder Head Bolts
Post by: Paull on April 07, 2014, 09:39:07 PM

Hi  matthewmosse,

I cant see it will make much difference.

My mate had an idea, open the 12 treaded holes up to 10mm tread put a 10mm tread on the studs then turn them down to 8mm (the bit sticking out) put an 8mm tread on the other end and they won't pull out. A lot of work but it might work.

I have stripped it down to bare bones today the top case has three helicoils, 4 snapped bolts and a chip.

I will stick it on the milling machine tomorrow then tig up the case.

All should be well, come Thursday (Bloody customer getting in the way).

Not much to do then :o :o :o :o

Why a 650 top end on a 500 bottom end is it a gearbox thing.

Paul

Title: Re: Cylinder Head Bolts
Post by: matthewmosse on April 07, 2014, 11:33:58 PM

The nearest bottom end I had to hand that had no top on it (if it fits a 500 then it will fit a 550 - think the holes for the barrels to locate in in the cases might be bigger on 550, the 500 bottom end may be a hybrid of 500 and 550 bits). I bought a 650 head and barrells dirt cheap, don't have a 650 bottom end but figued some extra ccs might help move the sidecar along a bit faster. I'm planning on restoring the 500's original engine, but in the meantime thought at some point a 550/650 hybrid built up from whatever bits I find best out of the pile of spares I've ammassed over the years.

Title: Re: Cylinder Head Bolts
Post by: Bryanj on April 08, 2014, 07:16:09 AM

Mat not much difference in the bore 550 to 650, the 650 was stroked to get the extra cc and if you fit the 650 crank and rods you need the 650 cam and sprocket as the 650 uses a hyvo cam chain which needs other mods etc, etc.

As to using studs with nuts i don't see a problem as long as decent grade steel was used with proper thick washers and flanged nuts

Title: Re: Cylinder Head Bolts
Post by: Paull on April 08, 2014, 06:51:53 PM

Thanks for the reassurance Chaps

Looks like I am barking up the right tree (or just barking).

I would like to know how that goes mat.

Bryan do you still have neutral switches? ( and if so, ba ba ba )

Washed the engine parts today (cases, head, barrels etc), just got to drill them out retread um and weld one up.

Then I can get the bottom end back together.

Thanks

Paul

Title: Re: Cylinder Head Bolts
Post by: Bryanj on April 09, 2014, 03:44:44 PM

I got 500/550 neutral switches, both parts NOS but not super chear

Title: Re: Cylinder Head Bolts
Post by: Paull on April 09, 2014, 06:39:05 PM

Hi Bryan,

Will they fit a 650?

If so message me price and all that.

Thanks

Paul 

Title: Re: Cylinder Head Bolts
Post by: Bryanj on April 10, 2014, 09:26:38 AM

The rotor is the same but the stater has a different part number, as to wether it can be modified to fit i dont know for certain but i expect so. if you have the old one and can send me a pic to blj@blj.org.uk i will compare to what i have

Title: Re: Cylinder Head Bolts
Post by: Paull on April 14, 2014, 10:04:40 PM

HI Bryan

It  looks like a 550 neutral switch to me.

So If you have one i will have it.

Thanks

Paul

Title: Re: Cylinder Head Bolts
Post by: Bryanj on April 16, 2014, 07:27:07 AM

Have sent you two PM's, if you haven't got them please email me on blj@blj.org.uk.