BSA B50 -500 APG Build

[Koncretekid]

Quote:

But my runs at BUB were amazing!  They are as follows: (500 APS-PG)
8/25, 11:03, 70.1*, DA:5900ft, wind 0, down run: 141.029
8/25, 12:01, 71.2*m DA:5990, wind 3 mph NE, return run: 144.714
Average speed:142.871 mph
8/26, 7:56, 68.8*, DA 5829, wind 6 SE, down run: 144.042
8/26, 9:16, 71.5*, DA 5983, wind 0, return run: 142.616
Average speed:143.239

Why isn't the average 143.329 ?

FREUD

Yes, I like your number better!

I thought I also should mention why my roadrace bike ignition quit at Miller.  Luckily, the problem dawned on me during my drive home.  I thought the Boyer had malfunctioned because in spite of the battery still reading 12.3 volts, the voltage dropped to around 5 volts when I turned on the ignition.  I changed Boyer boxes but it still wouldn't run.  When I got home, I hooked up another battery and the motor started and ran fine.  It seems that one of my battery tenders (Canadian Tire brand) had overcharged the gel battery and damaged something internally.  It would still read full voltage, but would not allow enough current to flow to run the ignition.  New battery; problem solved. I could have been up and running for my next race if I had thought of it.
Tom

[wobblywalrus]

Your records are on the list.  They are pretty solid and might be there for awhile.   

[tauruck]

Lousy one Tom. To figure that one out after the fact hurts. IMO it's human nature to look for the most complicated problem first instead of the simple one. I could give an example of what happened to me and how stupid I was at the time but admin doesn't allow foul language here!. . Backup batteries are a must.

[Koncretekid]

Your records are on the list.  They are pretty solid and might be there for awhile.   

Thanks, Bo,
We had a great year, as I have said, and we hope for longevity. Frankly, I'm not sure why I went so fast but will be putting the bike on the dyno next weekend, so I hope to find the secret.  In any case, I really can't fathom anything to do next, but bump up to the next class.

Lousy one Tom. To figure that one out after the fact hurts. IMO it's human nature to look for the most complicated problem first instead of the simple one. I could give an example of what happened to me and how stupid I was at the time but admin doesn't allow foul language here!. . Backup batteries are a must.

Sometimes in the heat of the battle, we don't think straight.  My pit man, Ed, had left earlier in the day, so I was on my own.  At least I thought of the solution on the long drive home and it was correct -- consolation!
Tom

[DND]

Maybe a Backup charger too!!

[wobblywalrus]

One thing left to do is to bump the compression way up, run alcohol, and tune it like a speedway bike.

[DND]

How can you do that as they only go full tilt for 300 feet or so at a time LOL

[Koncretekid]

One thing left to do is to bump the compression way up, run alcohol, and tune it like a speedway bike.

Bo,
I'm already at 13.25 to 1 CR, squish clearance at .035", piston to valve clearance .050-.060". With the short stroke motor, higher CRs are difficult without welding up the head, machining a smaller combustion chamber (bathtub?), and re-profiling the piston to match.  Of course, there's always nitrous oxide or supercharging....................food for thought!  But B50 motors are getting scarce and they simply aren't making them anymore.  Here's one I found recently - - former boat anchor, I think.
Tom

[wobblywalrus]

I never thought about the distance issue.  You would need to start at Mile 2-3/4 and race somewhere that does not require a return run.

Are you thinking of getting a different engine or modding the one you have to run as a 600 against the 750's?

[Koncretekid]

Luckily, we have a 650 class, Bo!  So, yes, a 600 against the 650s.

[Koncretekid]

I just assembled my 2014 motor and quickly installed it in the bike the day before I had to come back to Nova Scotia.  The new motor will be 598cc.  The cylinder and crankshaft were salvaged from the "rust bucket" motor shown above.
Tom

[Old Scrambler]

Nice Bling 8-) 8-) 8-)

I have a feeling more than a few of the 650-twin teams will be surprised

[Freud]

...tekid.................those are F A N T A S T I C  pictures.

DEAD NUTS ON.

FREUD

[wobblywalrus]

Those look like 500 cc engine sized flywheels.  This might cure some of the vibe problem.

[tauruck]

That looks nice. Good that you're getting ready ahead of time.