Dr. Shop Teacher's Tonic le Moto--Broncco T-XL

Been a few days, but things are moving. I got the welds ground down on Sunday and started finish sanding the frame today. There is a lot of light pitting and I decided to smooth the welds as much as possible. I used an orbital sander and 60 grit, pad sander with 50 grit and a "triangle" finish sander for the tight stuff. The dremel came in handy too. The frame is a little under half done in the photos.
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Awesome work so far Pete ...I dig it !
 
Almost a roller: got the frame back but still don't have the rims and the handlebars. Powdercoater caught h*ll getting the color to go on smoothly. Certain Prismatic powers are a bear--so be careful when picking a color. Spent the day assembling the main portions of the bike and will kick start the engine tomorrow. Sorry for the full images, but the color needs to jump. Pollen was non-stop today, so pollen dust just kept coming.
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Finally, she's a roller: decided to powder coat the wheels and the handlebars in chrome. The wheels turned out pretty well, given the amount of corrosion over the years. The handlebars are a bit better, but the worst of the pitting didn't blast out after a ton of sanding. You'll see the chain tensioners courtesy of @mrpat in the last of the thumbnail pics. The axles are 200mm pit bike cut to length and threaded. I used pit bike controls with vintage jackhammer grips (I love 'em). So a blend of old and new!
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The week from h*ll: Mom's back in the hospital and my sister in law passed away unexpectedly, so things have been crazy in a not so good way. Photos below are prep work to start assembling the engine, which is a challenge as I've never built anything other than stock--couple of tools I have to pick up to add to the collection.

Intake port matching. I scribed a line on the intake side to increase the port and to line up with the manifold which I offset just a tad to be sure there was clearance for the flange bolts.
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Then I used my Dremel tool to grind it out and rough up the intake port.
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Next up was cleaning the rust off the crankshaft ends on both sides. This is an older 130202 crank, so I also had to cut the shaft to work with a modern recoil starter.
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I had originally presed out the brass sleeve for the governor, but realized there was not enough "meat" to properly thread and plug hole. I heated the block and reinserted the sleeve. I used a coarse thread cap screw and permanent Loctite to seal it.
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As you would on any Briggs rebuild, you have to true the manifold flanges and surfaces. In this case, my fabbed manifold needed the same. I trued the mating surface on the block with 400 grit wet and dry using a 3x3 piece of angle aluminum. The same was repeated on both ends of the manifold.
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Lastly, I chased the head bolt holes and gave the block a thorough cleaning in the sink. I did not do any work on the eyebrows as this is a 135XXX block and it has the canted valves like a Raptor II.
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Starting assembly: I'm using the stock valves as the engine came off a low hour tiller. I cleaned them up with a wire wheel and the lapped the valves.
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The valve guides were lubed with 30 wgt oil. I used a Q-tip to make sure the guides were clear and then well lubed. In the photo below, you can see the difference in valve springs: stock on the left and the 18# Dynocam spring on the right. Springs are matched to the cam I selected (a mild Superstock cam). I also have new Dynocam lifters. I soaked the springs in 30 wgt oil before installation.
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I have new seals for both the magneto and PTO sides. I popped out the magneto side, cleaned out the surfaces and oiler hole and drove a new seal in with a wooden block.
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I am using the stock piston as this is a Kool Bore block (not sleeved) with stock rings. I disassembled the piston from the stock rod, popped the rings off, cleaned them and reinstalled in the same order and orientation, after soaking in oil. I'm using a 3.875 (stock length) ARC Billet Rod. I marked the piston to properly orient the rod and attached slinger, soaked in oil and assembled.
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Finally, I rummaged around my stash of gaskets and found one that would serve between the block and manifold flange. I scribed it, cut with a knife and ground the edges to match the manifold flange shape.
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Just for kicks, I mounted the Chi-kuni i picked up from NR Racing. Have to re-jet before it is ready. You'll see I powder coated the manifold the same color as the bike.
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Making stuff fit inside the block: Started on the internals today. Was able to pick up the right Plasticgauge at the auto parts store this morning. The process is pretty simple, but time consuming. Once I had the rod on the crank, it was just a matter of torquing the rod in 20# increments to 170#, following ARC's instructions. The gauge read at .0025, right where ARC said was ideal.
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I'm using a mild Dynocams Superstock cam and new Dynocam lifters. Nice and polished as opposed to the stock grind.
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I used a dab of red paint to mark the crank to line up the cam. The bearing makes it a bear to get everything lined up. I used plenty of 30 wgt oil on the cam, crank and lifters.
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Then the fun began. I inserted the piston and rod after lubing both the skirt of the piston and the cylinder wall--which I had given a very light hone (even though Briggs says not to on a Kool Bore).
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I went to install the rod cap, and started rotating the crank around to get the bolts so I could put them in...The oil slinger was hitting against the forward side of the block. So I called ARC to find out if I had ordered the wrong rod...I hadn't as my rod is 3.875" and is stock length. The technician pulled out an IC block and checked was I was telling him about. There's a rib across the forward side and that needed to be eased a bit to clear the slinger. I traced around the slinger to locate the area.
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I used a cut off wheel on the Dremel to create the groove needed. It's longer than the rib because the slinger was hitting the case also. The groove is in the area where an oil sensor would be located, so I don't think I weakened the block at all. I made sure I had about 3/32" clearance.

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Of course, the entire block had to be cleaned and wiped down along with the crank, rod, cap and piston. I had to re-lube everything before starting assembly again.
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Finally on to the side cover, I cleaned it one more time, put on a stock gasket with a tad of oil and popped it in place. I inserted the new seal after I had the cover on, using a piece of pipe to drive it evenly.
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Here's a mock up of the flywheel...
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