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69 Posts
Discussion Starter · #1 · (Edited)
Here it finally is. The unveiling of XM-1 (Experiential Motorcycle #1) for the internet.

This is a project that started back in 1996 with a 78 Bonnie 750 motor in a milk crate in pieces and a 1974 Corbon Jentry chopper frame. the front end was from the 78 with longer tubes and the rear wheel was a 68. There isn't too much on this bike that was bought on the shelf almost everything i touched i had to grind, cut, weld, bend my self.

About 10 years ago I started building my first bike. It was a basket case 78 Triumph Bonneville 750 that I paid $500 for. I was a welder/fabricator with a vision but no knowledge of working on motorcycles or trends and styles. So I spent about 400 hrs in the first year either building the motor or thinking how can I make what I wanted then actually making it. Almost everything had to be hand made or massively modified to function.

First thing I did was rip apart the entire top end of the motor down to the connecting rods. I had the head re-machined/valve job and bored the jugs .060 over at Hutches in Wakefield MA. (Then I had to put it all back together). While I was waiting for parts I had the rear wheel rebuilt with a 130 Continental Blitz as I was going for a drag bike look and that was the widest I could get in the frame (before I knew about jack shafts) and I still had to machine custom spacers to move the brake drum/chain sprocket out to clear the tire. The rear wheel came off a 68 and the brake drum is on the left. I knew that I would have to make some kind of cross over linkage but I figured I would cross that bridge later.

As I got the motor back together the first major pain in the ass was it was a 74 Corbin Jentry frame (so I was told) and the earlier triumphs intakes were kicked at an angle and my 78 had straight intakes and the carbs couldn’t take the K&N coned air filters I wanted. So I had to design my own angled intake manifold so the carbs and filters would work as I didn’t know I could have just swapped out the heads prior to me sinking some bucks into this one.

Fast forward a bit and the engine is together sitting in the frame with wheels on the front and rear. What else is a kid going to do after building his first motor in his parents basement. Well I cut off the bottom of a 2-litter Sprite bottle and inverted it, hooked up a petcock and some tubing, through some gas in and kicked it. On the 3rd kick she fired right up and I almost **** my pants as I really wasn’t expecting it to work. The folks weren’t too happy.

A couple more weeks after that I knew the frame and motor wasn’t level and the 6” over tubes up front just wasn’t looking right for what I wanted and was screwing things up. Now I had to learn all about trail and steering geometry. The end result was stock length tubes was perfect for neutral trail (2” forward of the center line of the axel.) It slammed the front end, the motor and frame was perfectly level and it looked Badass with drag bars. My vision was coming together.

So now I ordered a set of stock length tubes from Franks Engineering or Forks by Frank, I forget the name exactly (sorry). To give you an idea of how long ago, Do you remember way back when U.P.S. went on strike? Well my tubes were in transit for 4 weeks because of it and I was friggen pissed.

While I was waiting for the new fork tubes I decide to rip apart the front wheel and have the hub powder coated gloss black and I was on the hunt for the “perfect” tire for up front. After going through dozens of catalogs and piles of magazines I found one that I had to have but the article didn’t say what it was. I brought the mag to Aero cycles in Medford MA and Paul contacted the magazine to get the info. The good news is it was a Metzeler Lazer, the bad news is it was out of production for a couple years. I was so bummed out. Paul pulled on his contacts and someone found a brand new one in a warehouse in Belgium for me. Repeat after me “Holy **** you got to be kidding me”.

Once again I had to put all of this back together.

The front fender was much easier as I bought some Harley front fender and had to chop off the mounts and make my own that fit the triumph lower legs. The end result was lowered the front fender and slid it back to shorten the look of the front of it.

I then bought some Jay Brake controls for the bars and a 2-button Arlen Ness switch housing for the high/low and horn on the clutch lever. Come to find out the micro switches are momentary and wont work with a hi/low unless I just want to flash my lights. So back into electronics 101 and I quickly found out that it’s easier to say D.P.D.T. instead of double pole double throw and I needed a D.P.D.T. magnetic latching relay and a D.P.D.T. micro switch. Well the micro switch didn’t fit the 2-button housing so I machined out the back of it to make room. The contacts were still to long and would touch the bars so I had to file off most of the contacts and only had about 1/16” to solder to. Just getting this headlight switch to work was almost a 40 hr project.

The rest of the bike wiring went fine and I ended up putting an electronic ignition in because I started screwing with the points and I could never get it back. (Note to self, quit while you’re ahead)

Pretty much all that was left at this point was the tank. I started seeing some teardrop tanks in different mags but there was no information on where they came from. I found a small Fat Katz add in the back of a mag and that was all I needed. So I contacted them and told them I liked the tank but I needed it to curve to fit over a triumph motor and I had to fit on a chopper frame. They threw a few terms at me like backbone and setback and I didn’t have the foggiest idea of what they were talking about. I explained my background and they talked me through it. They sent me some Fed-X packages with full size side views and I was able to hold it up to the frame and using a spotlight to cast a shadow I could draw the top of the tunnel and the bottom curve of the tank to match the motor and tank mounts. I also wanted it fitted with twin petcocks just because. 2 Pingle petcocks are twice as expensive as 1, funny how that works…

About 6 weeks later my aluminum tank showed up back at Aero Cycles and the cost was the same as if I was buying one of Fat Katz standard teardrop tanks for a Harley. Once again I was overly impressed with the lack of price gouging that was going on by all parties involved.

I was this close and I had to get the bike out of the folks basement and I didn’t have a place to finish it for 4 more years. Once I was up and running again I was able to finish it to the point of my test drive in about 3 more months. I had to get married, buy a house and have my first kid before I had a place to finish XM-1. My friends named it Frankenstein and that fits but I liked XM-1 (Experimental Motorcycle 1). Anyone that is into old school engineering and fabrication of test planes and such knows what I’m talking about.

I dressed the top of the headlight housing with a stock tach mounted slightly differently and a small liquid filled oil pressure gauge. This was a perfect setup as like I said earlier that I was going for a drag bike style and I have never seen a speedo on a real racecar or bike.

Last I had to make my own forward controls and proper linkage including that crossover for the rear brake that I mentioned earlier. I chose to make them out of some scrap titanium that I had kicking around. (Don’t ask, I have more **** these days and my small shop has grown to a 2 lathes, a Bridgeport, T.I.G. welder, plasma cutter and a few other goodies)

It was unpainted and raw and I didn’t care. I didn’t even have a seat yet. I rode it for about 2 months just sitting on a leather-welding glove to insulate my ass from getting zapped from the power distribution bar just below it. Finally my friend Shawne cut a piece of foam that I used for a seat for the entire next season. My original plan was to ride it and make sure everything was functional. Then rip it all down and finish cleaning up the frame and send it out to be powder coated then put it back together. I started the teardown 3 years ago but got sidetracked with life and kids again.

Last spring a friend let me ride his 76 harley chopper around the block during lunch at work. That was all it took. I spent the next 6 months in my shop 5-6 nights a week and for 4-5 hrs a night to finish the tear-down, re-fabricate the things i didn't like, powdercoat, and put everything back together.

The seat is a similar story. I fiberglassed the pan myself (with some assistance from my father as he is a boat guy) and i worked closely with the people at Danny Grey to come up with the design and shape of everything. They were awesome to work with. (Thanks again M.E.)

Special thanks to all my friends and family Shawn, Pete, Russ, Frank (my father) and my wife Kerry that helped me get by all the mental road blocks that i hit along the way, with different designs of things or just lending another set of hands when needed.

I have plenty more pics, just dont know how to get them up here


69 Posts
Discussion Starter · #7 · (Edited)
Awesome looking machine!
Can you give some insight on the rear drive chain with the idler?
what exactly are you looking for? the chain is a 120 that i had to add 4 or 6 links to.. it was years ago i did the chain so i dont remember the count exactly.

The idler was a process of trial and error. The final way you see it here is actually 3 different pcs of steel. first i made the axle. i made it out of 3/4" bar stock and turned down the shaft to fit thru the bearings of the skateboard wheel, while still leaving the 3/4" diameter about 3" long as it was going to bisect the vertical piece of 1" D.O.M. pipe, not just weld to the side of it.

After noting the height i needed the center of the wheel to be for a good location i was able to cope (or fish-mouth) out on the bottom of the 1" pipe where its TIG welded to the frame. Before welding it to the frame, I bored the 3/4" hole thru both sides of it for the axle. that allowed me to weld both sides of the axle to the vert pipe. then i just sanded of the backside (toward the center of the bike) of the axle on the vert pipe to give it a seamless look. Lastly i dressed of the top with a cone i turned quite simply on the lathe and gave the base a slight chamfer. that allowed good penetration of the weld so i could sand that off also....

unfortunately i didnt take pictures of all the things i did along the way as i would have spent more time documenting the bike instead of building it.... i may have some pics from different angles showing it more closely. hope it helps...


Super Moderator
14,154 Posts
A skateboard wheel chain tensioner! That is awesome. Good work.

In posting pix, just hit <enter> after each photo you insert in a message, it will place the next one below the last one. If you just keep inserting photos, they'll string along side by side.

Unless you pasted several photos together in one horizontal string with your photoshop program...

69 Posts
Discussion Starter · #11 ·
Botm Vote

Have you have ever had to Build your bike from a bucket of parts?

Hand fabricate a special bracket because what you need cant be bought in a magazine?

Build you bike to a vision that was in your head instead of just buying a production bike?

If you answered YES to any of these questions, you need to check out this months Bike Of The Month.

I wasn't going to post something like this but what the hell... It is at the half way point and its a 3 way tie for first place. All the bikes are cool and they all have their own unique stories along the way but i just don't get it....... They all look like an off the shelf production bike to me.

I wouldn't think buying a bike from a store and putting it in front of a "pretty" background classifies for winning BOTM although maybe im wrong. Its up to the people that take the time to vote.

Either way check it out and vote however you feel. (i had to say that)

Even if she isn't your style, you go to respect the work involved. The story says it all

here is a link to B.O.T.M.
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