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NIck, your car would absolutely get on the track at an SCCA "Track Night in America" thing. check your regional SCCA pages or just google Track Night in America.

If I want to get real track time with the B-3, I'm going to have to form my own driving club or something.

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The B-3 build log: http://www.locostusa.com/forums/viewtopic.php?f=36&t=13941

The Jag Special Build Log: http://www.locostusa.com/forums/viewtopic.php?f=36&t=19012

SCCA-SFR has its track nights at Thunderhill Raceway, quite a drive on a Thursday night. Plus it's Thunderhill. I might sign up for a track day with one of our local clubs, but only after I find a spare engine to replace the one I'll blow up.

Vibration Update...

Well, this was bound to happen.

The B-3's engine is a non-counter-balanced 3 cylinder with 120 degree crank throw spacing, and it pretty much shakes like a paint mixer, all the time. the vibration is especially noticeable on the drivers side, in the area of the forward exhaust pipe mount. As a result, I've had the driver side mirror vibrate off several times. (though the last fix seems robust enough).

Anyway, I was out there running it (no driving during the "Salty" months, but I'll open the G'raj door and run it a while to work condensation out of the engine and keep the battery healthy) and afterwards on the walk around noticed this...



Oh, Derp! Yup, 15,000+ miles had caused some cracking at the exhaust pipe hanger. Pulling the pipe off and cleaning off the paint revealed the full extent of the cracking.



Well, that's not kewl. I'd wanted to fit in a flex pipe at the downpipe/exhaust pipe joint anyway, to mitigate the harsh vibration at the mirror, and so that became the plan. I purchased a 6-inch, 2.0 in ID universal flex pipe at Autozone...



...and then made some reinforcing straps to spread the load out along the exhaust pipe. the pic below shows the forward strap in place for welding, after I'd gas-welded the cracks closed and ground them flat in the area I'd be reinforcing. I chose gas welding for the cracks, since that method creates a bit less heat-stress in the weld area.



Detail pic of the strap - its drilled for plug welds on top, for initial welding. after the initial welding I heated the edges yellow-hot and bashed them down onto the pipe for final welding. Gotta have a bit of blacksmithing and bashing with a hammer in there, just because.



...everything welded up, and test fit on the B-3. Mint, as they say...



flex pipe tentative placement for pipe cutting...



Exhaust pipe cut back about 5 inches, with smaller segment cut from the inlet and inserted at the correct angle for body clearance...



...and, everything welded up and test fit in place. I took about 2.5 inches off of the downpipe as well. The flex pipe slip-fit onto both the downpipe and the resectioned exhaust pipe inlet perfectly. In the pic, the flex pipe looks very close to the body, but there's actually about 3/8ths clearance at the closest point. All it needs is a couple band clamps and paint!



I'll tell ya, it's been so long, was really nice to be out there in the shop making sparks fly. Also, nice to know I still have my welding chops. A bit more wait time on the fabrication start of the Pamilcar, but this little repair really got the juices flowing nicely.

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The B-3 build log: http://www.locostusa.com/forums/viewtopic.php?f=36&t=13941

The Jag Special Build Log: http://www.locostusa.com/forums/viewtopic.php?f=36&t=19012

This almost inspires me to finish up my new exhaust with the giant muffler. Almost.

I know, right? I stared at those cracks for almost a month before getting my poop in a group and doing anything about it.

Do I really want to go thru this all again with the Pamilcar? ahrg. the only answer is "yes".

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The B-3 build log: http://www.locostusa.com/forums/viewtopic.php?f=36&t=13941

The Jag Special Build Log: http://www.locostusa.com/forums/viewtopic.php?f=36&t=19012

and I WILL be stealing that one!!!

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JD, father of Quinn, Son of a... Build Log
Quinn the Slotus:Ford 302 Powered, Mallock-Inspired, Tube Frame, Hillclimb Special
"Gonzo and friends: Last night must have been quite a night. Camelot moments, mechanical marvels, Rustoleum launches, flying squirrels, fru-fru tea cuppers, V8 envy, Ensure catch cans -- and it wasn't even a full moon." -- SeattleTom

Vibration is a big deal especially with motorcycles. It almost doesn't matter how strong you make something the fatigue gets to it somehow. I just did some figuring, and If you get 3 vibrations per revolution, at 5000 RPM that's about 65 minutes per million flex cycles. Hmm, that's in the area of a 100 million per oil change.

Hanging the system from one of those rubber donuts like they use on my wife's Toyota would fix it easy, but maybe it would look silly. My race car supports the pipe on a half circle of sheet metal and then uses a spring wrapped around the top half. It's spring like screen door style spring. It allows plenty of movement, but perhaps would make a racket on your car. In the race car you just don't notice because of all the terror.

Hope your fix works!

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Marcus Barrow - Car9 an open design community supported sports car for home builders!
SketchUp collection for LocostUSA: "Dream it, Build it, Drive it!"
Car9 Roadster information - models, drawings, resources etc.

Ouch!

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Chuck.

“Any suspension will work if you don’t let it.” - Colin Chapman

Visit my ongoing MGB Rustoration log: over HERE

Actually, that looks nice, Chuck! So, it's officially an option!

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Marcus Barrow - Car9 an open design community supported sports car for home builders!
SketchUp collection for LocostUSA: "Dream it, Build it, Drive it!"
Car9 Roadster information - models, drawings, resources etc.

Chuck I dig your mount.

Marcus, it really depends on the bike, I've had a couple that were very smooth. That Suzuki Burgman 650 I had was pretty much vibration fee, but that engine had a great driven counter-balancer.

The B-3 muffler is hard mounted at the back, at some point I'll likely modify that as well.

Motorcycle exhaust mounts are generally stiffer than car exhaust mounts, so I followed that philosophy with the B-3. The isolators I used are spitfire control arm bushings.

Yesterday it was sunny and warm and I worked from home, so I was able to paint the pipes. There's a few other things I've been meaning to do over the last couple years, so I'm going to take care of those thing now as well.

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The B-3 build log: http://www.locostusa.com/forums/viewtopic.php?f=36&t=13941

The Jag Special Build Log: http://www.locostusa.com/forums/viewtopic.php?f=36&t=19012

Hi Rob... I've just spent several days going through this file - 1-100 - and have enjoyed, and learned so much, from most of it. I am at the stage of gathering bits together to make my first one, so thanks for all the 'Pro-Tips'...
Best wishes, MangPong.

Marcus... Marcus! GET YOUR FOOT OUT OF YOUR MOUTH!!! You don't know where that thing might have been! Nasty!

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JD, father of Quinn, Son of a... Build Log
Quinn the Slotus:Ford 302 Powered, Mallock-Inspired, Tube Frame, Hillclimb Special
"Gonzo and friends: Last night must have been quite a night. Camelot moments, mechanical marvels, Rustoleum launches, flying squirrels, fru-fru tea cuppers, V8 envy, Ensure catch cans -- and it wasn't even a full moon." -- SeattleTom

Hey this thing just keeps on running, and even chases parts for the Pamilcar Jag Special, but sometimes it needs a bit of repair, being the thoroughbred it is. Thus...

Attachment:

turnsignal viddy greetz.JPG [ 61.95 KiB | Viewed 1199 times ]

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The B-3 build log: http://www.locostusa.com/forums/viewtopic.php?f=36&t=13941

The Jag Special Build Log: http://www.locostusa.com/forums/viewtopic.php?f=36&t=19012