Bonneville America Forums Forums Technical Forums Custom Corner Speedmaster Drag Bike Build

A year ago I bought an '05 SM engine off eBay for a ultra low $415. A few weeks ago, I bought an '05 SM frame, with a clean title, off eBay for an equally low $285. Since I already have a groovy '07 BA to travel the world and seven seas with my lady friend, I thought it would be fun to have a retarded play bike.

And so it starts...

That will be fun. Have you had a chance to start that motor yet.

Did I mention supercharger???

you cray

Anything to keep up with the Jones'. Oh, and the Berni's...

braaaappp!!

I like where this is going.

That there is purdy. You keeping the stock rear swing arm and rear tire or going to go oversize with it?

Stock swingarm for sure. I may add a couple inches to it, but not sure yet.

America or Thunderbird wire wheel hub laced with a wider aluminum rim.

Goodyear Eagle Pro Stock motorcycle drag slick. Goodyear Eagle Dragway Motorcycle Special Slicks

To go any wider than 200mm will require you to shim out the sprockets or run a jackshaft to put the chain outboard enough to clear the tire. And you will run out of spread with the swing arm as well. You should pick up one of these before the price goes normal or they are discontinued all together: 5.5x16_Excel

I need an 18" rim for that tire, or I would go that route. Also, I made a wooden mock-up tire to the specs of that drag slick. It JUST fits in the stock swingarm. If I stretch the arm a couple of inches, like I has thinking of doing, clearance should not be an issue. If the chain clearance is an issue, then I will probably go with a Free Spirits offset primary sprocket.

Free Spirits Offset Sprocket


Also, Ryk, did you see my PM a week or so ago?

How are you planning to spin that SC?

I will most likely run carbs for a while. But, I would do a belt drive setup off the left end of the crank, if/when it does happen.

You might want to look into beefing up your starter unless you'll use a slip-clutch set-up for the S/C belt.

The starter idler gear boss was broken when I bought the engine. I need to fix that before I great to far along. I am pretty sure that is why the engine was removed and sold. If I was to add a supercharger, I would use a handheld starter that attaches to the end of the crankshaft.

Slight progress, in the way of buying more junk. I scored an Adventurer rear wheel off eBay. The hub will get sandblasted, polished, laced with stainless spokes and nipples, and an aluminum 18" by 6" rim installed.



Ryk was super cool for keeping a Thunderbird Sport front hub for me. That will get the same treatment as the rear hub, and have a 17" by 2.5" aluminum rim installed.

I had Brent at New Speedmaster ordered me a set of Free Spirits Raked Triple Clamps. I dig 'em!!! Zmilim has a set of Speedmaster forks for me.

I received a set of Biltwell shock struts yesterday. They are "made" for Evo Sportsters, 10" eye to eye, with 1/2" bolt holes. I read on the reviews on the Biltwell page for the struts, and someone posted that they hogged the bolt holes out to 14mm, and installed them on a SM. So, I gave it a go! With the tire that I have picked out, without tire squat, the frame will be around 2 3/4" off the ground.

Low... Ride... Er...

Have you considered going darkside and putting a quality soft compound car tie on the back? A flatter tire profile has a bigger road contact patch on a straightaway.

No car tire for me. I think the 7" wide Goodyear drag slick will do a fine job...

Isn't that a soft compound car tire?

Not really. It's not a "car tire" as far as steel belted passenger car tire. It is a square tire, similar to what a Top Fuel dragster would use. The tire I will be using was made for Pro Stock Motorcycle racing.

Summit Racing

Almost. It does go up towards the rear, but just lightly. I think a 10.5" strut would make it flat. It would probably take an 11" shock to do the same.

Yesterday I received a set of SM forks from Z. Thanks Z!!!

Ride height is a little high, with the 4X4s, maybe an inch. But, this gives a good idea on how retarded this project is going to be...

you should have just bought a used busa

get another tat

Nah, more fun to do it the way he is doing it now.

Fab work makes me happy. I am not a rich b!tch that buys his toys, I build my $h!t. I may cost twice as much, but it is MINE in the end, and hopefully doesn't look like everyone else's junk.

I told myself that as soon as both ends were hanging, I was done for the year. I scored a dentless eBay tank over the weekend for $50. I am looking for fenders now.

I may end up installing street tires...

Weird, I scored a brand new tank for $50 this weekend too. Sometimes EBay rocks.

I scored a new bobbed Maverick fiberglass rear fender for $50 on eBay too. Not sure if I will be using it though.

I finally got around to uploading a photo with the tank and rear fender mocked up. Looking better. But, it still needs tires to be able to really see how this would turn out.

I have also been thinking of changing models. The big Thunderbirds are starting to catch my eyes...

Don't give up now, build up the motor you have. Or make yourself a Bobber, you have good start on one.

This project has went WAY off track. Originally, I planned to get a frame and swingarm to make a jig for a custom frame. Next thing I know, I keep buying stock parts. I wanted to use stock forks, brakes, wheels, etc., but on my own frame.

I wanted to build a modern "retro" version of the 1960's Hagon/Kosman drag bikes...

1966 style;







JAP engine style;



1970 style;



[image]http://i702.photobucket.com/albums/ww28/justin_calkins/Triumph/Hagon%20Drag%20Bikes/TriumphTopFlat_zpsdbbglxru.jpeg[/image]

Well you can build the frame you want, you need a quality tubing notcher, there are some effective ones that use hole saws and appropriate clamps that do not cost a fortune. Some 4130 or 4140 tubing as used in WW2 fighter plane frames, enough scrap for jigs to secure the tubes for welding and if you do not trust your own welding, tack it up then find someone like me with a tig machine in their garage along with the appropriate skills. I would sew a frame up for you for free, just to be part of a cool project. You have a bike to ride, so slow down your timelime and it will eventually come together. Or build it as an alternate rider. Look on the positive side, you have many parts you can utilise from the frame you have now, such as a frame neck and the forks to fit, the motor mounts ready to be transplanted to the frame you build, a good jumpstart on what you want to build. I will even loan you precision levels and mercury plumb bobs if you ask. BTW, I have been building a 750 twin Kawa Bobber for three years (the design keeps evolving), no big rush, because it's for me.

Between our full service shop at work, my rat rod building buddy here in town, my hot rod building and CNC shop working buddy an hour away, and my drag bike and tool and die shop owning buddy an hour away, I hope I can make it happen like I want.

The idea from the beginning was to design a frame that looked like the '60's tire smokers I posted above. Use a modern air cooled Triumph twin for power. Use Triumph Modern Classic bolt ons, like forks, wheels, and brakes. And have it all come together in the retro style that makes the Modern Classic series such a neat deal.

The tires will be wider than the '60's version, and I may be forced to add a wheelie bar. Modern tracks, modern tires, and a lack of power tells me that this scooter will not be a tire smoker. Rather, a clutch slipping gear grabber.

really looking forward to see the progress on this

I have plans for the frame jig I plan to build for the custom frame project, and have started to make a steel list. I keep dragging my feet on that side of this deal. So, I ordered more parts!!

The front tire showed up today, all $265 of it. I think it looks killer...