Found the leak path

[fredintoon]

I was on a small bike rally right after an expensive rebuild on my BSA 250 engine when I noticed the thing had developed a major oil leak but what can you do 200 miles from home except top up and hope? Every time I stopped for gas I bought a quart of oil and topped up the oil tank. The last top-up was 7 miles short of making it home when the piston seized in the cylinder so I made those last 7 miles in the back of a pickup truck.
I finally got around to fixing the thing and freed up & rebuilt the engine. Then I started looking for the oil leak. Turns out that whoever had refurbished the oil tank had re-brazed the oil return spigot and left a smear of bronze on the spigot face seal that held the fibre washers just enough open to leak oil and that I hadn't noticed it. It really shows how a small defect can cause a major problem.

[olebiker]

What year is the 250 Fred? That was my first real bike after building and riding moped style machines. I have no idea how old that one I had was. It was a 250 single with a three speed tranny. Not much body work other than a seat and tank. Never did have a working front brake. Was not much of a machine but I sure had a lot of fun with it. At 14 or 15 years old I thought I was on top of the world on that old thing. Good memories.

[fredintoon]

Worth a fortune?

Hi Carl,
Mh BSA is a 1970 B25SS. The motor/tranny on all of BSA's late model singles was developed from the 150cc Triumph Terrier/200cc Triumph Tiger Cub unit.
Most likely yours was a C11 but I thought those were 4-speeds? Did it have:-
girder forks or tele-forks?
Rigid rear, plungers or swingarm?
A separate tranny rather than a semi-unit?
Any of those old bikes have value these days and if it turns out yours was a 1932/35 B-33-3 Blue Star junior you can join the regiment of bikers who once owned rare bikes that'd sell for a fortune and are wishing they had a time machine and a telephone.

[olebiker]

Separate trany hard tail and for the life of me I can't remember the front end. I would guess that the vintage was late 40s or early fifties. I am pretty sure about the three speeds. I remember being impressed that the Bantam that I picked up had 4. But I never did get much riding on that. It would shear the key way every time I got it running. I believe I pushed it more than I ever rode it. It was a 175 I think. We all rode old cobbled together clunkers back then and no one had any money so we often tried to resolder cable ends and just do anything we could to make them go. Rode many miles with not much more than a throttle and sometimes a back brake. That old 250 screw on top on the carb was stripped and would sometimes pop off leaving the thing wide open. Of course there was never a kill switch or even an ignition switch. Threw me in the ditch one time and landed on top of me. Amazing how strong and quick you are when the hot pipe lands on you. The good old days I have no idea how I survived them.

[fredintoon]

Mr Stupid strikes again

I got my BSA back together with all new oil lines and a re-faced oil tank connector. Then I tried to get it running. Not a single pop. Ignition OK. Valve timing on the marks & clearances correct. Remove and soak clean the carb (You can do that with an Amal because the rubber bits are removable) Still not a pop. So the bike gets trailered to the Handhills Small Bike Rally in the hope that someone can spot the problem. Two BSA experts push me out of the way, check things out and say "Aha! It can't run if the pushrods are operating the wrong valves, right?"
15 minutes later and it's running!

[egsols]

Two BSA experts push me out of the way, check things out and say "Aha! It can't run if the pushrods are operating the wrong valves, right?"

Now we're getting political, all this sucking and blowing at the same time.

No worries, none of us is infallible.

[fredintoon]

Further to the BSA starting

20 miles down the road towards lunch the ignition timing slips and the BSA and I end up arriving at the pub in the rally sweeper truck. (Stupid bolt not tight enough; 1/4"BSF with a cratered-out Phillips head) The ladies operating the truck, (one of them my wife!), say, the truck is too small for 3, find your own way back. I cadge a ride back as a passenger in Franklin's Filipino Taxi sidecar rig. Which blows out it's sidecar tire an downtown Drumheller. I must be cursed, eh?

[egsols]

I must be cursed, eh?

And a cursing Saskatchewanian in Alberta

[olebiker]

Might be just as well that the tire gave out in town and not on the highway. I have never driven a sidecar but I would think that a flat with a passenger might be a handful if you had any speed on.

[fredintoon]

"I would think that a flat with a passenger might be a handful if you had any speed o

Hi Carl,
Franklin's Filipino taxi has worked it's way up from being hauled by a 100cc Kawasaki and is now on it's 4th tug, a 500cc twin Honda. However, what with the stainless steel sidecar body, the massive sidecar frame and the square tube support for the canopy, plus the aerodynamic drag of the canopy itself, "speed" is definitely NOT one of the rig's assets. I reckon we were going pretty well flat out when the sidecar tire blew, perhaps 30mph. After the tire blew the rig simply rode all bumpy and pulled to the right a little.

[olebiker]

I can understand that I had a buddy that I used to teach the course with that rode a vespa with a sidecar. It is the only one I have ever seen. I don't think it would do much more than that when it was empty. He sure did get lots of attention when he would show up on the first night of the course riding that rig.

[fredintoon]

Running again!

I finally got my arse in gear and fixed the BSA. Yes, the ignition timing plate had slipped around to spark at BDC or thereabouts. So I reset it to the proper marks and did up that cratered-out Phillips head fastener (and if anyone knows of a reasonable Canadian source for a 2" long 1/4"BSF Allen screw I'd be real grateful) with a big Phillips point in my air percussion wrench. Hopefully that'll hold the bastard. Fired up on the 3rd kick and I took it on a triumphant tour around the block.

[blue giant]

Fred,
2"- 1/4 x20 SS cap screw with a hex socket?

Maybe!

[fredintoon]

coarse thread swaps, fine thread don't.

Hi Paul,
1/4"Whitworth and 1/4"UNC coincidentally have the same 20TPI thread pitch which has allowed me to use North American 1/4UNC Allen screws to replace the cratered out 1/4W Phillips screws on the BSA's engine covers despite the American 60º thread angle vs the Whitworth's 55º.
Alas, the 1/4" BSF (British Standard Fine) thread has a 26TPI pitch so the readily available 1/4"UNF fastener's 28TPI just won't work.

[blue giant]

Sorry Fred, All I have is 1/4 20 and 1/4 28.

Paul