B50 valve lifter to bare casting.

Here you can talk about all kind of TECH for the B50 B44 B25 And Other BSA unit Singles

Moderator: minetymenace

Post Reply
Armstrong Phil
>10
>10
Posts: 19
Joined: Mon Aug 10, 2020 11:00 pm
Location: Brum, Blighty.
Has thanked: 0
Been thanked: 0
Flag: Great Britain

B50 valve lifter to bare casting.

Post by Armstrong Phil » Mon Aug 31, 2020 3:29 pm

Hi, I have a B50 without a valve lifter fitted. To preserve what knees I have left I intend to fit a valve lifter. I have managed to source all the required parts, just need to remove and machine the rocker box.
Do I simply drill and ream a hole to take the shaft, or is it counter bored to take the o ring. If so does anyone know the size and depth of the counter bored?
I've also been sold a plain washer to go next to the o ring, should this not be a stepped washer to locate the o ring?
Phil

User avatar
minetymenace
Gerry1
Gerry1
Posts: 7702
Joined: Wed May 26, 2004 1:00 am
Location: On the edge of Salisbury Plain, England
Has thanked: 33 times
Been thanked: 95 times
Flag: England
Contact:

Re: B50 valve lifter to bare casting.

Post by minetymenace » Mon Aug 31, 2020 4:13 pm

The standard shaft did not have an O ring (Correction: Oh yes it did!!!), if you do a search you should be able to find details of others who have modded the hole to take an o-ring.

There are other methods of decompression if you don't want to go the valve lifter route, others have fitted a chainsaw decompresser in the head (search) also.

Someone technical will come along with the answer to reaming the hole, but it seems you know what you are doing....

What about swapping the cover for someone who already has a lifter and doesn't use it?
There is no evidence to support the notion that life is serious.
Abyssinian Wire-Haired Tripehounds Gnash.

beesa71
>320
>320
Posts: 331
Joined: Thu Sep 09, 2004 5:04 pm
Location: Cheshire, UK
Has thanked: 0
Been thanked: 9 times
Flag: Great Britain
Contact:

Re: B50 valve lifter to bare casting.

Post by beesa71 » Mon Aug 31, 2020 4:44 pm

Phil,

I’m a little surprised you have a B50 rocker box without provision for the valve lifter components. I’ve never seen one un-machined for it.

Have you had a good luck/can you attach some pictures, I’m curious.

Regards to all OIF’ers.

Paul.

Armstrong Phil
>10
>10
Posts: 19
Joined: Mon Aug 10, 2020 11:00 pm
Location: Brum, Blighty.
Has thanked: 0
Been thanked: 0
Flag: Great Britain

Re: B50 valve lifter to bare casting.

Post by Armstrong Phil » Mon Aug 31, 2020 9:18 pm

Now I've taken a picture and been able to magnify it I'm not sure if it's unmachined or if it's been plugged. I will find out when I remove it (going to do the replacing studs with Allen bolt mod when Allen bolts turn up)

Armstrong Phil
>10
>10
Posts: 19
Joined: Mon Aug 10, 2020 11:00 pm
Location: Brum, Blighty.
Has thanked: 0
Been thanked: 0
Flag: Great Britain

Re: B50 valve lifter to bare casting.

Post by Armstrong Phil » Mon Aug 31, 2020 9:20 pm

IMG_20200831_210531961_copy_864x1152.jpg
B50 head
Now I've taken a picture and been able to magnify it I'm not sure if it's unmachined or if it's been plugged. I will find out when I remove it (going to do the replacing studs with Allen bolt mod when Allen bolts turn up)

beesa71
>320
>320
Posts: 331
Joined: Thu Sep 09, 2004 5:04 pm
Location: Cheshire, UK
Has thanked: 0
Been thanked: 9 times
Flag: Great Britain
Contact:

Re: B50 valve lifter to bare casting.

Post by beesa71 » Mon Aug 31, 2020 9:31 pm

My bet is plugged.

User avatar
kommando
>1400
>1400
Posts: 1964
Joined: Mon May 24, 2004 8:41 pm
Location: Scotland
Has thanked: 9 times
Been thanked: 51 times
Flag: Ireland

Re: B50 valve lifter to bare casting.

Post by kommando » Tue Sep 01, 2020 8:14 am

Looks plugged to me, someone had an oil leak and preferred a dodgy knee ?

Armstrong Phil
>10
>10
Posts: 19
Joined: Mon Aug 10, 2020 11:00 pm
Location: Brum, Blighty.
Has thanked: 0
Been thanked: 0
Flag: Great Britain

Re: B50 valve lifter to bare casting.

Post by Armstrong Phil » Tue Sep 01, 2020 11:48 am

Just checked the parts book (72 publication ref 00-5732), it does look like an o ring was standard, number 35, at least on later bikes. Is there an earlier parts book that shows one without it?
PhotoPictureResizer_20200901_113916_copy_1843x1382.jpg

User avatar
kommando
>1400
>1400
Posts: 1964
Joined: Mon May 24, 2004 8:41 pm
Location: Scotland
Has thanked: 9 times
Been thanked: 51 times
Flag: Ireland

Re: B50 valve lifter to bare casting.

Post by kommando » Tue Sep 01, 2020 7:53 pm

My B40 has an O ring, assumed they were standard.

User avatar
minetymenace
Gerry1
Gerry1
Posts: 7702
Joined: Wed May 26, 2004 1:00 am
Location: On the edge of Salisbury Plain, England
Has thanked: 33 times
Been thanked: 95 times
Flag: England
Contact:

Re: B50 valve lifter to bare casting.

Post by minetymenace » Wed Sep 02, 2020 2:23 pm

Apologies, I have checked all over the place and don't know where I got the idea that there was no O-ring, there is and always has been as far as I can see....sorry. Now I'm all confused as I'm sure there was some mention of machining a recess in the cover to take the O-ring, perhaps because no dished washers were available...I'm going for the "senior moment" excuse... :oops: sorry.
There is no evidence to support the notion that life is serious.
Abyssinian Wire-Haired Tripehounds Gnash.

User avatar
SteveS
>540
>540
Posts: 547
Joined: Mon Jul 10, 2006 8:28 pm
Location: Nuneaton, Warks. U.K.
Has thanked: 1 time
Been thanked: 14 times
Flag: England

Re: B50 valve lifter to bare casting.

Post by SteveS » Wed Sep 02, 2020 4:55 pm

Hi Gerry

Was it this discussion?
These users thanked the author SteveS for the post:
minetymenace (Thu Sep 03, 2020 9:27 am)
Rating: 25%
Steve Sewell

User avatar
FGF
>80
>80
Posts: 81
Joined: Sat May 11, 2019 3:14 pm
Location: Orleans
Has thanked: 18 times
Been thanked: 1 time
Flag: France

Re: B50 valve lifter to bare casting.

Post by FGF » Thu Sep 03, 2020 4:11 pm

Hello Phil ,

if you don't want to worry about it , Peter Quick ( BSA unit Single ) sell all the parts and even a little bush
with all the advises to fit it . ( new O rings ...)

the thickness of your rocker box must have the same value than the others , nearly sure ...

Canberra
>1200
>1200
Posts: 1293
Joined: Fri Sep 03, 2004 11:45 am
Location: Canberra, Australia
Has thanked: 0
Been thanked: 14 times
Flag: Australia
Contact:

Re: B50 valve lifter to bare casting.

Post by Canberra » Fri Sep 04, 2020 12:03 am

My CCM rocker box came with capped hole. I just pushed out the cap and the bored hole came with the recess for the o-ring. One day I'll get around to bushing it. That o-ring works until you get a bit of wear in the aluminium's bore then the dreaded oil leaks come. Even replacing o-rings does not work after a while.

John

beat
>1400
>1400
Posts: 5709
Joined: Sun Jun 04, 2006 5:33 pm
Location: Switzerland
Has thanked: 0
Been thanked: 46 times
Flag: Switzerland

Re: B50 valve lifter to bare casting.

Post by beat » Fri Sep 04, 2020 8:06 pm

sorry, -- but IMO, the all valve lifter device is bbbilllsshittttt :!:
why they di'd not do something proved as it is by the Vater of it, the Goldie :?: :?:

unknown...
:oops:

Armstrong Phil
>10
>10
Posts: 19
Joined: Mon Aug 10, 2020 11:00 pm
Location: Brum, Blighty.
Has thanked: 0
Been thanked: 0
Flag: Great Britain

Re: B50 valve lifter to bare casting.

Post by Armstrong Phil » Fri Sep 04, 2020 11:23 pm

Personally I love the half compression lever on my panther m100, it makes it really easy to start and doesn't leak!

Armstrong Phil
>10
>10
Posts: 19
Joined: Mon Aug 10, 2020 11:00 pm
Location: Brum, Blighty.
Has thanked: 0
Been thanked: 0
Flag: Great Britain

Re: B50 valve lifter to bare casting.

Post by Armstrong Phil » Tue Sep 15, 2020 10:26 am

Finally got the rocker box off and it was just plugged, even the recess for the o ring was intact.
PhotoPictureResizer_20200915_102147_copy_864x1152.jpg

Armstrong Phil
>10
>10
Posts: 19
Joined: Mon Aug 10, 2020 11:00 pm
Location: Brum, Blighty.
Has thanked: 0
Been thanked: 0
Flag: Great Britain

Re: B50 valve lifter to bare casting.

Post by Armstrong Phil » Tue Sep 15, 2020 11:11 am

Now I know why it was plugged, the lifter arm is very sloppy in the bore, I'll have to rebush it, found an old A10 valve guide that I can turn down to do the job, just the right internal bore, if only I can find my ream!

Armstrong Phil
>10
>10
Posts: 19
Joined: Mon Aug 10, 2020 11:00 pm
Location: Brum, Blighty.
Has thanked: 0
Been thanked: 0
Flag: Great Britain

Re: B50 valve lifter to bare casting.

Post by Armstrong Phil » Tue Sep 15, 2020 9:25 pm

Ran the ream through the bush, couldn't get the lifter through the hole and the arm wouldn't go on the splines. Turns out the lifter had been played making it oversize, managed to remove it to get it to fit, don't you just love pattern parts!
Just got to weld up and dress the contact area on the rocker and fit it tomorrow.

Armstrong Phil
>10
>10
Posts: 19
Joined: Mon Aug 10, 2020 11:00 pm
Location: Brum, Blighty.
Has thanked: 0
Been thanked: 0
Flag: Great Britain

Re: B50 valve lifter to bare casting.

Post by Armstrong Phil » Wed Sep 16, 2020 10:33 pm

All done, came to fit rocker box to find someone had helicoiled four holes, but hadn't bothered to dress the raised bits where the previous studs had pulled out, it beggars belief what some people are capable of! Still got one hole with stripped thread so have ordered a helicoil kit to fix it, typically it is not accessable in situ so head has to come off, at least I can skim the mating surface flat!

User avatar
minetymenace
Gerry1
Gerry1
Posts: 7702
Joined: Wed May 26, 2004 1:00 am
Location: On the edge of Salisbury Plain, England
Has thanked: 33 times
Been thanked: 95 times
Flag: England
Contact:

Re: B50 valve lifter to bare casting.

Post by minetymenace » Thu Sep 17, 2020 9:10 am

That will teach you for buying an old bike! When you take the head off you will find the liner cracked so off comes the barrel, then you'll see a worrying mark on the con rod, the oil pump, gearbox, frame, forks, swinging arm....and just to add a niggling doubt, how far in did the previous owner delve? What other howlers are lurking in the depths of your engine?

No worries, you have the weekend coming up, and everyone here to give you advice! Keep up the good work. :thumb
There is no evidence to support the notion that life is serious.
Abyssinian Wire-Haired Tripehounds Gnash.

Armstrong Phil
>10
>10
Posts: 19
Joined: Mon Aug 10, 2020 11:00 pm
Location: Brum, Blighty.
Has thanked: 0
Been thanked: 0
Flag: Great Britain

Re: B50 valve lifter to bare casting.

Post by Armstrong Phil » Thu Sep 17, 2020 11:11 am

Good job I do this for fun!

Malcolms Lad
>220
>220
Posts: 233
Joined: Fri Feb 23, 2007 12:01 pm
Location: Birmingham, England
Has thanked: 0
Been thanked: 1 time
Flag: England

Re: B50 valve lifter to bare casting.

Post by Malcolms Lad » Sat Sep 19, 2020 8:49 pm

Nice work... Where abouts in brum are you? I'm a flyaway resident now residing in Tamworth.... Originally from Castle Brom.

Brummies Unite! lol
How to rupture yourself in one easy lesson!

Armstrong Phil
>10
>10
Posts: 19
Joined: Mon Aug 10, 2020 11:00 pm
Location: Brum, Blighty.
Has thanked: 0
Been thanked: 0
Flag: Great Britain

Re: B50 valve lifter to bare casting.

Post by Armstrong Phil » Sat Sep 19, 2020 10:12 pm

I'm a Lancashire lad, been exiled to Birmingham for 28 years, Kings Norton.

Armstrong Phil
>10
>10
Posts: 19
Joined: Mon Aug 10, 2020 11:00 pm
Location: Brum, Blighty.
Has thanked: 0
Been thanked: 0
Flag: Great Britain

Re: B50 valve lifter to bare casting.

Post by Armstrong Phil » Sun Sep 20, 2020 10:40 pm

Found another issue, someone had fitted overlong dowels to the head, preventing rocker box seating flat. At least that's an easy fix!

beat
>1400
>1400
Posts: 5709
Joined: Sun Jun 04, 2006 5:33 pm
Location: Switzerland
Has thanked: 0
Been thanked: 46 times
Flag: Switzerland

Re: B50 valve lifter to bare casting.

Post by beat » Mon Sep 21, 2020 7:19 pm

how long is this overlong dowel ( in mm please )

beat

Armstrong Phil
>10
>10
Posts: 19
Joined: Mon Aug 10, 2020 11:00 pm
Location: Brum, Blighty.
Has thanked: 0
Been thanked: 0
Flag: Great Britain

Re: B50 valve lifter to bare casting.

Post by Armstrong Phil » Tue Sep 22, 2020 10:15 am

About 0.7 mm, when measuring bare casting, gasket approx .5mm thick so would have been holding rocker box 0.2mm away from head. No wonder someone had gorilla tightened the nuts to try to get it to seal. I've had to lap the rocker box to get it flat again

Jeff K
>1300
>1300
Posts: 1342
Joined: Sun Jul 13, 2014 12:30 pm
Location: Bay City, Michigan USA
Has thanked: 54 times
Been thanked: 22 times
Flag: United States of America

Re: B50 valve lifter to bare casting.

Post by Jeff K » Tue Sep 22, 2020 7:00 pm

Do the B50's have the same problem as the B40 & B44"s with the many different head gasket thicknesses? I ran into this with a B40, the Cylinder wall lip would hit the head before the gasket had completely sealed. Turns out the B40 copper gasket is thicker then the b44. Well documented in the Ratio book and by me in posts in here. And are the dowels seated completely, if some one removed them and then pushed them back in, they may have knurled a burl in the hole.
Jeff

beat
>1400
>1400
Posts: 5709
Joined: Sun Jun 04, 2006 5:33 pm
Location: Switzerland
Has thanked: 0
Been thanked: 46 times
Flag: Switzerland

Re: B50 valve lifter to bare casting.

Post by beat » Tue Sep 22, 2020 7:26 pm

I just made new Dowels because they are missing.

Total lenght is 9 mm.

but I will carefully check for good contact of rocker box to head.
thanks for the advice

beat

skippy
>1400
>1400
Posts: 1487
Joined: Mon Dec 19, 2011 3:25 am
Location: Horsham Vic Australia
Has thanked: 54 times
Been thanked: 14 times
Flag: Australia

Re: B50 valve lifter to bare casting.

Post by skippy » Wed Sep 23, 2020 12:23 am

beat wrote:
Tue Sep 22, 2020 7:26 pm
I just made new Dowels because they are missing
I made mine from a metal ring of a pen it worked perfectly. I am not sure i could find another pen with that size ring on it now. :roll: :roll:
Doug
Should never have sold them old motorbikes

Post Reply