BSA B50 -500 APG Build

[Old Scrambler]

Tom..........you have to remember to replicate the factory 'runs' :lol: :lol:

[Rex Schimmer]

Tom,
I have to agree that the frame really looks great!!! Your paint job is meticulous and makes the frame really look finished. Great job!!

Rex

[tauruck]

Lovely paint man. That's cool. It looks fast already. Way to go! 

[wobblywalrus]

Be careful to give it plenty of cure time before a second coat.  A lot of these new paints tend to blister up the previously applied coat.  It looks good and new paint always adds a few mph. 

[Koncretekid]

I just realized I should have hit the "enhance" button on the photo program.  It shows the frame in much better light.  Thanks for the complements.  It also shows up my nicely painted floor.
Tom

[tauruck]

Even better. Those new pics really show it off. Remember when you were battling with the welding?. Loooong gone. Have one on me.

[Frank06]

Tom, looking good!

[Koncretekid]

Upon re-assembly, some things popped up.  First photo is of the headstock bearings after two seasons at Bonneville.  Note to self - -disassemble the headstock upon returning from the Salt Flats!  The good news is that these are just cheap trailer wheel bearings - - $12.95 at Princess Auto.

The second photo is a method of thinning up an aluminum shim.  I made this shim by parting it off of a piece of aluminum in the lathe, but my little Taiwanese lathe doesn't turn slow enough and I couldn't get a clean cut.  So I taped it down to a flat piece of aluminum in the mill drill using only double sided Scotch tape.  I milled off .004" per cut until I got the shim thinned up sufficiently.  It sits in the headstock under the outer race to prevent the bearing cage from interfering with the headstock bearing seat (cage is proud of the outer race, so it bottoms out before the bearings themselves seat).

Third photo is of the newly installed bearings.

Fourth photo shows re-assembly of the bike.  Almost a shame to cover it up with bodywork.  I'm going to have to clean up all the other parts now.  I leave in a couple of weeks for Colorado (leaving the bike in N.S.) so I'm trying to get it put back together before I go.  I don't get back until 3rd week of June, just 3 weeks before Loring.

Tom

[tauruck]

I can't believe how the bearings and cups rusted like that. Now I understand the term salt. Don't you grease those bearings? The bike looks lovely now. You might even win a show or two.

[Graham in Aus]

Wow, bike looks stunning Tom, very nice! 

[wobblywalrus]

Mike, the salt is bad stuff.  Tom's bike is an example.  There are a lot of fenders and fairings to keep the salt away from those bearings and the problem still happens.  There are some things a person can do, like use a lot of stainless steel, 6061 aluminum, and titanium in the build.  Care in washing helps. too.  The trick is to wash from the top down with a stream of cold water rather than a spray of hot water.  Coating stuff with a thin layer of grease or some commercial products helps.  Marine grade anti-seize works good for lubing a lot of things like steering head bearings.  It is not a good idea for high speed bearings, like the ones in wheels.  Even with all of the protective measures, it is amazing how much corrosion happens.   

[Peter Jack]

Actually the 5xxx series aluminums are a better choice. They're the materials used in boat hulls for salt water use.

Pete

[Koncretekid]

Mikey, and others,
Yes, I used grease, but not the marine grade type that Bo mentioned.  I thought I had repacked them before the 2012 season, but maybe not.  My headstock bearings are much more susceptible to this kind of damage because although there is a seal at the top and at the bottom, the headstock is open and salt plus washing water enters from within where there are no seals. On my wheel bearings, I have removed the inner seal, but left the outer one in place.  If I spin my rear wheel by hand (without the chain), it will still rotate for up to 10 minutes, so I believe the seals are effective.  The other most affected part is the chain.  Remove it, wash it in solvent, then wash it at least twice more in soap and hot water, then again in solvent or WD-40 (better) and finally oil it and store it in a zip-lock bag.  Polished aluminum seems to hold up OK, but raw aluminum pits almost as badly as raw steel.  A good paint job on aluminum and steel also seems to hold up, but you have to clean and inspect it, because any scratches will start to breed rust.  Some stainless steels, probably marine grades are good, but cheaper grades also come back with a haze of brown on them.  High strength bolts rust faster than lower grade, in spite of the nice gold finish they apply to a lot of them.  The only sure way to keep everything clean is to disassemble, clean, and wax or oil it.  Look for cracks in the frame while you're at it!
Tom

[tauruck]

I had the chance to live at the coast but I wouldn't go because of the rust. It's evil and I feel for you Tom but it looks like you're on top of it now. Maybe some powdercoating on some of the parts might help. Ones that aren't stressed. The High tensile stuff even rusts up here at 6000ft. If it's an Allen head the water sits in there and it corrodes for sure.

[Koncretekid]

Just an update to show new 4" extended intake to increase distance to valve to 11-1/2". I also made a bracket that screws to the back of the carburetor and to the bottom of the seat to hopefully prevent carb from falling off.  I had to relocate the oil filter and make a longer throttle cable, but it all works.  I would like to try to make some intermediate length intakes as well, but the seat gets in the way if I don't include a drop as well as an extension.  I plan to add an exhaust extractor as well as I have outlined on the tech forum.
Tom