Exhaust parts for the dirtbike

We got a box of love from the good folks at Burns Stainless yesterday. They were kind enough to do all of the engineering on our 2-1 merge collector exhaust, and supply us with a merge collector and an ultralight megaphone muffler. Quality doesn't really cover it, Burns' stuff is flawless.

Now we've got to make an exhaust!

Dirt bike project update...fun with cylinder heads

I've been working on the Atom Bomb/RaceTech Suspension dirt bike project a bit evenings and weekends. Since this is a long weekend I decided to figure out what to do about the stock splayed port carb setup, since each carb stuck out roughly 4" past where my knees will be when riding this thing in anger.Not to mention, I have to put an exhaust collector back there somewhere.

I very nearly went to the dark side and put a single carb TR7 head on this bike. Luckily they're IMPOSSIBLE to find (even though I've had like three TR7s through here in the past year). I was so focused on a single carb head that I almost modifed a late TR6 head and used that. Then I smacked myself in the face and realized how lame it'd be to take the easy route. Back to my original plan of making a twin carb setup take up less space.

After determining that simply making manifolds that pointed straight back wasn't gonna cut it, I decided to get serious and make a parallell port head out of the stock T140 splayed port deal, which looks like such (all these pics get bigger if you click them):



First step was mill the flanges as flat as possible and fill the mounting holes, which would be useless to me:

Then I welded all that mess up enough to get a flat surface, and milled it again:

Since we're also moving the ports inboard, I determined that I needed to add some more material to build the pad up. Did that, then milled flat once again. Once I had my flat mounting base, I sort of roughed in the ports (very rough) so I could locate my manifolds.

All marked up and mounting holes drilled:



With that out of the way it was time to shape the outsides of the new flanges and the ports. Here's what the new and improved head looks like all done. It was a TON of work to not only get the ports lined up and sized properly, but make it all look more or less like it came that way. Pay no attention to the valve guides, I knocked them flat on top so I could clamp the head on the mill. I didn't want to put the head through all these heat cycles with no guides in it.



In this next picture you can see that I left some weld visible on the inboard side of the flanges. Got lazy. You CANNOT see it when the head is on the bike, so I'ma let it fly. You'll also notice that I had to weld probably 1 1/2" down into the ports to add enough material to shift everything. Not fun, don't recommend it. But it did allow me to carry the port in dead straight and the right size/shape.

Here's what the whole deal looks like on the bike. Carbs are tucked in nice and tight!

Funny what you find inside old engines...

We're getting ready to build a street tracker for a client in New York. He picked up the donor, a Trackmaster frame with a '67 unit Triumph motor and brought it down here a little while back. It's got Betor forks, Barnes quick change hubs, and as it turns out one HELL of a motor.

We pulled the exhaust off the other day. At the other end of the ports (which are pretty large-ish) were the largest exhaust valves I have EVER seen in a Triumph motor. One of them happened to be all the way open too, and I promise it was far enough off the seat to stick a finger into. Big, BIG lift. Pulled off the rocker covers and discovered lightened, polished and shimmed rockers, with aluminum nuts locking the adjusters.

So then we decided to unscrew the intake manifolds because it was easier than unbolting the carbs. The carbs, by the way have "250 main" written on the top of them hahaha. What we found was that the carb bodies and manifolds have been concentric bored as a unit. Dead smooth from one end to the other. And the intake valves are in taper cut guides, and the heads on those valves are probably 1.75"...so big you can see where they rewelded the ports to put the big seats in.

So then we pulled the timing cover, where we found the following:

Drilled, thinned, beveled, polished, you name it. Nicest timing gears I've ever seen. Through the inspection hole we could see that the crank has been lightened, and had Mallory metal added to the counterweights. It's got some sort of steel H beam rods, and I forgot to mention, they're attached to the big old pistons of a 750 Morgo kit. Oh, and we noticed right at the last second it's a 5 speed.

I can't wait to get into the thick of this project in a few months. I suspect it's going to be quick, and it's damn sure going to be trick!

Gear from Geared Up Designs

We got something in the mail today from our friend Ava at Geared Up Designs. Using old motorbike parts, Ava makes some great little items to spruce up your office, home and garage; everything from helmet hooks to lamps, and even amazing coffee tables.

She was kind enough to send us a business card holder for our new showroom (or my desk in my super secret hidden office!) and it's a really cool piece. A well thought out arrangement of parts all carefully cleaned and TIG welded together, no popping it together with a blob of MIG weld here! I love the piece she sent us, it reminds me of an old winged tire logo. Check out a few pictures of it, as well as one of her coffee table that we swiped from her Facebook, because she doesn't have pictures of it on her official site.

Ask and I shall get

Like how I didn't want to try and spell recieve in the title? Spelling is hard. At any rate, the other day when I posted about our new building, I mentioned that my damn awning still wasn't here 7 weeks after it had been ordered. Thanks to the power of my words as typed on the Internet, it showed up the next day.

Pardon the Interruption, but we moved and stuff

I'm not even sure the last six weeks really happened. Somehow between May 15 and now we manged to get our selves, our household, and the entire shop moved to Richmond VA, 180 miles away from our old home base in Salem. The moving part was pretty painless, with only one major box truck fire and one shredded trailer tire. Pretty typical and uneventful.

After a week spent getting everything here, attention turned to renovating our commercial building which was last used in 2007. Turns out after meeting and talking to a lot of our new neighbors, this building has had a pretty interesting list of tenants including a non inspected (read: illegal) catering outfit, a counterfeit (read: illegal) DVD burning operation, and an "underground" (read, yes, illegal) strip club complete with a galvanized water pipe for a pole. So, yeah, we ought to fit right in.

Now it's ours. Walls were knocked down. Plumbing was repaired. 14 gallons of paint were installed, just on the inside. Wires were added, removed, relocated...lots and lots of wires because Atom Bomb has lots and lots of power requirements. The compressed air system was plumbed. The HVAC (yes, in the WHOLE building) was tuned up and brought online. A hand painted sign went up out front.

Truth be told, the last six weeks has sucked so badly (and I've slept so little) that I don't remember the specifics of a lot of it, just a fog of a "This Old Building" meets "Groundhog Day", specifically where Bill Murray slugs that guy in the street. The one thing I DO remember is all the folks that have helped over the last six weeks with moving, working on the building, moral support, wisecracks, etc. Old friends, clients, and folks we'd never met until we moved here...the list is so long that I don't want to even try to thank everyone by name but you all know who you are, please know that Erin and I appreciate the hell out of it.

So tomorrow I get to work on bikes again. I've got a lot to do for a lot of patient folks, thanks to all of our clients for putting up with us and our move. It'll be a minute before I start on any "new" projects, I've got some loose ends to finish up from before the move, but there's plenty of new Atom Bomb builds in the queue for later this summer and well into next year (maybe even some stuff with rear suspension!)

So enough exhausted rambling, here's some pictures of our new digs. We've still got a few tiny things to do like outlet covers and whatnot, but I HAVE to go back to work before I go more insane. And our awning for the front isn't here yet, but there's one coming. Supposedly. Don't get me started on the damn awning. The pictures get larger if you click them, it's magic.


The front of the place before paint. It looks narrow because it is, only 22 feet wide. 150 feel long though, so it works out.

Front after paint:

Hand painted sign, y'all:

Pics of our lounge and showroom area. Soon to be chock full of goodies and my collection of vintage stuffs:

The shop, from many angles:

That's all folks. You don't get to see the offices, or the storage area. We're mysterious like that. Huge thanks again to everyone that lent a hand!!

Atom Bomb relocating to Richmond VA

Atom Bomb Custom Motorcycles is headed to Richmond VA to set up shop! On May 15 we take possession of a building in the historic Scott's Addition section of Richmond to begin transforming it into our new shop, complete with a retail showroom, service department, and of course ample area to continue building our award winning custom bikes.

Our showroom will be fully stocked with builder parts and other goodies from Lowbrow Customs, LC Fab, Biltwell and a host of others as well as replacement parts for British motorcycles. Hopefully even a little bit of local art.

Added space in our new facility will finally allow us to offer "carry out" fabrication work. We'll be able to offer our famous custom frames as well as frame straightening and repair, custom fuel tanks/fenders/oil tanks in steel or aluminum, and of course bars, exhaust etc.

We're very excited to move to Richmond. With it's great central location, positive atmosphere, and excellent access to services and materials, we feel like Richmond will be a great home for us. More details and a grand opening party will follow shortly.

As always, thanks to our friends, fans and clients for all of your support. We'd also like to extend a huge thanks to our friends at Lowbrow Customs, Biltwell, Race Tech, Woodward Fab, and all of the other folks that make this stuff possible for us, and finally the guys at Velocity Cycles for making us feel at home. There might just be a few Atom Bomb/Velocity custom Enfields in the near future!