Little BSS cafe racer

Here you can publish Your projects bikes.
Only BSA singles

Moderator: minetymenace

Post Reply
FGF
>20
>20
Posts: 21
Joined: Sat May 11, 2019 3:14 pm
Location: Orleans
Has thanked: 0
Been thanked: 0
Flag: France

Little BSS cafe racer

Post by FGF » Thu Oct 17, 2019 9:15 am

Hello ,
i've just bought a B50SS from UK. My brother had one in the seventies.
i'd like to make a cafe racer but still use it on road.
i write ''little '' because when i see all the great project bikes on this kind web site , mine would be very modest.

for the beginning , changing the oil before running , i find a hole in the sump plate filter .
The seal is made with paste .
in the frame i drain a few volume of oil , a lot of it in the primary case and the front filter screen on the frame has
a lot of little bits of seal paste .

i think that the scavenge pump has eaten them and risk to have been stopped. i think i must not run like this...?
teh engine has a good compression but...

do you know if i can dismantle the pump with the engine in the frame, without dismantle the timing pinions ?
i have no puller for them ...

thanks
Francois

User avatar
minetymenace
Gerry1
Gerry1
Posts: 7433
Joined: Wed May 26, 2004 1:00 am
Location: On the edge of Salisbury Plain, England
Has thanked: 14 times
Been thanked: 51 times
Flag: England
Contact:

Re: Little BSS cafe racer

Post by minetymenace » Thu Oct 17, 2019 10:22 am

Yes, you can take the oil pump out without pulling the timing gear off. You need to remove the studs, I have done this by locking two half nuts on the studs, but you may find there is not enough room in which case you may have to resort to a pair of mole (vice) grips but this will bu&&er up the threads and the stud will have to be replaced during re-assembly.

If someone has been over enthusiastic with the goo, you should consider a complete strip down as you sludge trap will probably be full.....
There is no evidence to support the notion that life is serious.
Abyssinian Wire-Haired Tripehounds Gnash.

User avatar
kommando
>1400
>1400
Posts: 1847
Joined: Mon May 24, 2004 8:41 pm
Location: Scotland
Has thanked: 4 times
Been thanked: 30 times
Flag: Ireland

Re: Little BSS cafe racer

Post by kommando » Thu Oct 17, 2019 6:02 pm

When you put it back together use Loctite 518, this is anaerobic, it only sets with no air present, so any excess squeezed out of the joint stays liquid and dissolves in the oil or wipes off the outside. Result is not bits of sealant collecting in filters or oilways blocking oil.

FGF
>20
>20
Posts: 21
Joined: Sat May 11, 2019 3:14 pm
Location: Orleans
Has thanked: 0
Been thanked: 0
Flag: France

Re: Little BSS cafe racer

Post by FGF » Thu Oct 17, 2019 6:19 pm

Thanks a lot.
let' go easy...slowly

FGF
>20
>20
Posts: 21
Joined: Sat May 11, 2019 3:14 pm
Location: Orleans
Has thanked: 0
Been thanked: 0
Flag: France

Re: Little BSS cafe racer

Post by FGF » Fri Oct 18, 2019 9:27 am

sorry , i still search answers from the owner's manual ...and i have read the rupert ratio too.
my english is perhaps too poor..

i don't find how to strip the sump ball valve ? i have to clean and cut it's end pipe to change the sump filter .
is it inserted in the oil pump ? i believe not

you fairly advise me to use loctite 518 :
behind the pump plate i see a plane gasket , so you think the 518 is even necessary ?

Thanks
Francois

User avatar
minetymenace
Gerry1
Gerry1
Posts: 7433
Joined: Wed May 26, 2004 1:00 am
Location: On the edge of Salisbury Plain, England
Has thanked: 14 times
Been thanked: 51 times
Flag: England
Contact:

Re: Little BSS cafe racer

Post by minetymenace » Fri Oct 18, 2019 10:50 am

The pipe is a push fit, can be gently teased out with a pair of pliers (maybe put a dowel up the pipe to prevent crushing), or screw a suitable bolt or self tapper into the pipe an pull, maybe a bit of heat.

Consider lost of solvent (petrol perhaps) and an airline rather than taking it apart if you are nervous.....
There is no evidence to support the notion that life is serious.
Abyssinian Wire-Haired Tripehounds Gnash.

User avatar
kommando
>1400
>1400
Posts: 1847
Joined: Mon May 24, 2004 8:41 pm
Location: Scotland
Has thanked: 4 times
Been thanked: 30 times
Flag: Ireland

Re: Little BSS cafe racer

Post by kommando » Fri Oct 18, 2019 10:58 am

you fairly advise me to use loctite 518 :
behind the pump plate i see a plane gasket , so you think the 518 is even necessary ?
On a sump gasket I put the 518 on one side and a thin smear of grease on the other, the 518 goes on the side of the gasket where I want the gasket to stay on removing the sump plate, the grease allows the sump plate to be removed easily.

FGF
>20
>20
Posts: 21
Joined: Sat May 11, 2019 3:14 pm
Location: Orleans
Has thanked: 0
Been thanked: 0
Flag: France

Re: Little BSS cafe racer

Post by FGF » Fri Nov 08, 2019 7:21 pm

Hello
the new sump plate is fitted, even filled with new oil to start.
with the wassel electronic ignition , the bike is started easyly , i was really surprised . it run and idle fairly...great

but ......the scavenge pump spited two or three times before stopping its work.
so i have just run the engine a few minutes
perso.jpg
the little B50 project
changing oil , the scavenge pump start quickly ? i mustn't run longer like this ?
i think the scavenge valve is correct , but it is difficult to feel if the ball really move or not..

so the only way is to dismantle the pump case ?

later , i 'll enjoy to change the camshaft for a MX one and a maybe a 34 mm carb if the big end is in good condition.
thanks for your advises

beat
>1400
>1400
Posts: 5542
Joined: Sun Jun 04, 2006 5:33 pm
Location: Switzerland
Has thanked: 0
Been thanked: 28 times
Flag: Switzerland

Re: Little BSS cafe racer

Post by beat » Sat Nov 09, 2019 8:38 pm

hi francois
FGF wrote:
Fri Nov 08, 2019 7:21 pm
the scavenge pump spited two or three times before stopping its work.
the big question is: dos it have oil in the sump - ore dos the engine " storidge " the oil in the primary case ?

some of this " english masterpieces " ( as mine ), tendences to bulk up to one liter oil in the clutch case.
this means, for a long period NO oil is coming back to the tank.

as a result, - if there is not enough oil in the tank, - the feed pump and the engine is running dry !

beat <201

FGF
>20
>20
Posts: 21
Joined: Sat May 11, 2019 3:14 pm
Location: Orleans
Has thanked: 0
Been thanked: 0
Flag: France

Re: Little BSS cafe racer

Post by FGF » Mon Nov 11, 2019 10:43 am

thanks Beat ,
i'd have a look with the primary case .

i 'll put some new oil in the pushrod hole by the cylinder head and try again .
if it doesn't work , go to timing case dismantling...

i work slowly because i 'm not really good equipped.
i 'm very amazed to see how some of you seem to have a professionnal skill !
very impressive
i carry on anyway , the bike is here...

User avatar
kommando
>1400
>1400
Posts: 1847
Joined: Mon May 24, 2004 8:41 pm
Location: Scotland
Has thanked: 4 times
Been thanked: 30 times
Flag: Ireland

Re: Little BSS cafe racer

Post by kommando » Mon Nov 11, 2019 11:48 am

Think of the oil pump as 2 pumps, the feed side is critical, the return side is less critical as if it stops returning the feed side will still run under the tank level drops giving a few minutes supply. If the feed side works then testing the return side can be performed as long as the tank is kept topped up.

FGF
>20
>20
Posts: 21
Joined: Sat May 11, 2019 3:14 pm
Location: Orleans
Has thanked: 0
Been thanked: 0
Flag: France

Re: Little BSS cafe racer

Post by FGF » Mon Nov 11, 2019 3:43 pm

Good thanks,
so i can try a little again with oil in the pushrod hole.

the only way to know if the feed pump is working in good condition
is to see the tank level decrease ? and then the big end get oil...

my luck is a fair starting engine !

User avatar
koncretekid
>860
>860
Posts: 862
Joined: Sun Nov 20, 2005 1:22 am
Location: Yarmouth, Nova Scotia
Has thanked: 2 times
Been thanked: 9 times
Flag: Canada

Re: Little BSS cafe racer

Post by koncretekid » Mon Nov 11, 2019 4:13 pm

Did you get the sump spigot out to check the ball (sometimes rusted or plugged up)? I found that by tapping the hole to 6mm x1mm (someone else had posted that on this forum, thank you), I could screw in a fairly long 6mm bolt with enough threads to place a nut and a spacer (socket that is slightly larger than the body of the spigot), I could just tighten the nut down to pull the spigot out. There is a small pin that holds the ball in that quite often is rusty but can be carefully drifted out and replaced along with the ball.

I should mention that with the '71 cases, the passageway that goes from the sump to the oil pump sometimes breaks thru thru the inside of the cases, but you can't see it unless you split the cases as can be seen here. Obviously, the pump can't draw the oil up the passage if there is an open hole in the crankcases until the oil rises to the level of the hole. Look at the small hole in the cases in this photo:

Image

Tom
life's uncertain - go fast now

FGF
>20
>20
Posts: 21
Joined: Sat May 11, 2019 3:14 pm
Location: Orleans
Has thanked: 0
Been thanked: 0
Flag: France

Re: Little BSS cafe racer

Post by FGF » Fri Jan 24, 2020 4:50 pm

Hello Koncretekid ,

i did'nt answer because i was working on the old electrical wiring .
a friend has welded my outer timing case for the worn ignition threads .

i 've cleaned the non return feed valve . i'vnot seen any trouble on it.

i was scared about your photo which shows a bad tiny hole...i hope if my case had it that the problem has been solved
for long time before...

i 'll try to fire it when the case come back and force -feed the engine with oil before to see if the pump wake up.

then , strip all to fit the head with a bigger carb with an MX cam. i 've read many many posts for the carb...

has someone found a spigot to fit a mikuni vm 34 without machining the welded plate of the frame ?
allens_mikuni.jpg
allens parts
for the vm 34 the center distance would be 50.8 and often many spigots have a different size .
however , if you use this way of fitting , is it a good solution ?

many thanks

beat
>1400
>1400
Posts: 5542
Joined: Sun Jun 04, 2006 5:33 pm
Location: Switzerland
Has thanked: 0
Been thanked: 28 times
Flag: Switzerland

Re: Little BSS cafe racer

Post by beat » Fri Jan 24, 2020 9:49 pm

hi francoise

is not the distance A by 70 mm for the VM34 ?? ?

this means, the zylinderhead nead some welding work to make it fit.

I do use a Mik TM 32 on my bike, but with a very short selfmade spigot because there is very smal space for the carb on the Cheney frame.

in general, this nitrile rubber spigots are avery good solution IMO.

the problem is to make it fit by the long distance of the fixing bolts.

beat

User avatar
koncretekid
>860
>860
Posts: 862
Joined: Sun Nov 20, 2005 1:22 am
Location: Yarmouth, Nova Scotia
Has thanked: 2 times
Been thanked: 9 times
Flag: Canada

Re: Little BSS cafe racer

Post by koncretekid » Fri Jan 24, 2020 11:07 pm

Check with Sudco. I think they made this adapter that came with my TM34 that I bought on eBay (NOS) from a previous owner. However, fitting it on a B50 may be a problem.
Image
Tom
life's uncertain - go fast now

FGF
>20
>20
Posts: 21
Joined: Sat May 11, 2019 3:14 pm
Location: Orleans
Has thanked: 0
Been thanked: 0
Flag: France

Re: Little BSS cafe racer

Post by FGF » Sat Jan 25, 2020 11:00 am

Hello ,

i think it 's possible to use the plate manifold with A=70 and cut it and drill two new holes with A=50.8 .

but , does someone use such a manifold and can tell if it's a good way ....no air leak ?
for the fitting , may be it 's possible to remove the studs and put two helicoils with screws to have a larger gap .

Hi Beat , your selfmade spigot has a diamond shape area ? i saw one of these , difficult to machine ...

French B50 rider , MX or racer , often cut a large hole in the frame gusset . i 'm not ready for this way .

i have to try it but i 'm not yet sure to choose the 32 or 34 to fit with a PES MX camshaft .

User avatar
minetymenace
Gerry1
Gerry1
Posts: 7433
Joined: Wed May 26, 2004 1:00 am
Location: On the edge of Salisbury Plain, England
Has thanked: 14 times
Been thanked: 51 times
Flag: England
Contact:

Re: Little BSS cafe racer

Post by minetymenace » Sat Jan 25, 2020 12:49 pm

There is enough meat on the original manifold to turn it down to a round that will take a cylindrical sleeve. PES are set up to do this..
There is no evidence to support the notion that life is serious.
Abyssinian Wire-Haired Tripehounds Gnash.

FGF
>20
>20
Posts: 21
Joined: Sat May 11, 2019 3:14 pm
Location: Orleans
Has thanked: 0
Been thanked: 0
Flag: France

Re: Little BSS cafe racer

Post by FGF » Sat Jan 25, 2020 5:21 pm

Thanks Minetymenace.

you're wright of course , because i made a big mistake , if i drill new holes at 50.8 , i cross the O ring groove , sorry.

i 'm afraid that the machining will be expensive, but i 'll ask to Mark .

beat
>1400
>1400
Posts: 5542
Joined: Sun Jun 04, 2006 5:33 pm
Location: Switzerland
Has thanked: 0
Been thanked: 28 times
Flag: Switzerland

Re: Little BSS cafe racer

Post by beat » Sun Jan 26, 2020 10:02 pm

FGF wrote:
Sat Jan 25, 2020 11:00 am
Hi Beat , your selfmade spigot has a diamond shape area ? i saw one of these , difficult to machine ...

diamond shape area :?: :?:
( I have no money for diamonds :lol: :lol: )

the self-made short spigot is to se in the Topic " MIKUNI TM 32-1 FLATSLIDE on B50 "
it is in the " Tech " section

beat
Last edited by minetymenace on Mon Jan 27, 2020 8:51 am, edited 2 times in total.
Reason: Link added

B44Claus
>160
>160
Posts: 169
Joined: Fri Jul 07, 2006 12:49 pm
Location: Denmark
Has thanked: 3 times
Been thanked: 1 time
Flag: Denmark

Re: Little BSS cafe racer

Post by B44Claus » Mon Jan 27, 2020 9:32 am

Hi Francois,

If I was you I would just buy a plate manifold for a VM32 and enlarge the hole "C" to 34 mm. If it's rubber you can cut it with a sharp knife, - if it's steel you can file it to the larger diameter. The plate manifold for the VM32 will fit directly to the cylinder head as it has the bolt distance of 2" / 50,8 mm.

Brgds,
Claus
B44Claus

FGF
>20
>20
Posts: 21
Joined: Sat May 11, 2019 3:14 pm
Location: Orleans
Has thanked: 0
Been thanked: 0
Flag: France

Re: Little BSS cafe racer

Post by FGF » Mon Jan 27, 2020 5:59 pm

Hi Claus ,

Thanks , i 've send an email to Allens about this way . it 's a good idea .
Cutting C from 33 up to 34.5 will be a delicate work to have a smooth face but even possible.

My french B50 will not be so fast than an english one but , i hope not ridiculous at the end.

i 'm looking for a fuel tank too, does anyone know the mail of '' The tank shop '' in scotland , expensive but kind ...

User avatar
minetymenace
Gerry1
Gerry1
Posts: 7433
Joined: Wed May 26, 2004 1:00 am
Location: On the edge of Salisbury Plain, England
Has thanked: 14 times
Been thanked: 51 times
Flag: England
Contact:

Re: Little BSS cafe racer

Post by minetymenace » Mon Jan 27, 2020 6:13 pm

John Williams
Glen View,
Glenmidge
Auldgirth,
Dumfries
DG2 0SW,
UK
There is no evidence to support the notion that life is serious.
Abyssinian Wire-Haired Tripehounds Gnash.

beat
>1400
>1400
Posts: 5542
Joined: Sun Jun 04, 2006 5:33 pm
Location: Switzerland
Has thanked: 0
Been thanked: 28 times
Flag: Switzerland

Re: Little BSS cafe racer

Post by beat » Mon Jan 27, 2020 8:50 pm

FGF wrote:
Mon Jan 27, 2020 5:59 pm
Cutting C from 33 up to 34.5 will be a delicate work
Rubber should be removed by grinding, - not by cutting.

beat <201

Post Reply