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Doomed to Fail: The SteamRat Build!

110K views 240 replies 16 participants last post by  spotarama 
#1 ·
It's me again, Margaret!


Aaaaaaaaaaaaaand I'm back with another build. I call it Doomed to Fail: The SteamRat Build. Why Doomed to Fail? If you have to ask, you haven't seen any of my build threads ever....but I'll give you a hint. I haven't finished a single fucking one.

Whats a SteamRat? The premise of the final look is a cross between steampunk and ratbike. Wouldn't that just be some Mad Max outlands, zombie apocolypse type of build, you ask? Nope.


So here's the break down. Been doing a bunch of planning, and I've got a couple parts on hand I've been dying to install on SOMETHING, I've got some ideas I haven't seen done on ANYTHING (seen similar, but close only counts with hand grenades and nukes), and its about goddamn time I do some fucking work...on 2 wheels.

Here's what I'm starting with:

$20 KZ650 frame. No title, bare frame, cut after the shocks, and has races installed for some AllBalls for the steering stem. Had the 5-0 run the numbers for me, it's clean, I'll have no problems getting a title. I should probably do that soon, before I cut this thing in half.



I'm not even using the entire frame. I'm cutting the backbone off, and cutting the bottom tubes right before they bend up. My intent is to build this into a low slung hardtail.

Parts on hand:
Kz650 frame
pair of aircraft control pedals courtesy of Mongo
wide oval low beam projector from an Infiniti QX4
the overwelming urge to put something together

Things I intend to incorporate into this build:
16hp cast iron Briggs & Stratton single cylinder with electric starter and 20amp stator
pair of springer seats
girder front end
kz750 19/16 wheels
Ford Model A taillight with STOP lense and led board

Everything else:
Whatever comes around and seems like a good idea



Already found a front end, or at least part of it. Next pay day I gotta see what I have left, and go make an offer on it. I don't even care that it's incomplete. I can build around it.



I'm also picking up a my motor from MarksA-C. Gonna need a little work to be usable, but that's fine. I like doing work.


Right about now I wish I still had this one exhaust pipe that was always laying around my stash. Tossed it as part of a massive downsize a year and a half ago (relationship issues....). Damn, it would have been perfect for this.

All my previous builds have been based on complete bikes, this will be an almost entirely ground up build.


I've done all the math, and while this won't exactly be a fast bike, it'll have a proposed top speed of almost 90. In no way do I expect it to cruise at that speed. If I can cruise at 70 I'll be happy. I'm building this mostly for around town and county roads.

16hp Briggs, right angle gear box, gokart/golf cart cvt, 18T/46T sprocket set, and 130-90-16 rear tire. The CVT runs a 3:1-1:1 range, so if anyone else wants to run my numbers, I came up with a technical top speed of 88mph based on the 3k rpm limit of your average small engine. Yes, a lot of times we run them higher, I'll be adjusting the governor to give me 3300-3400 at the top. Much higher and you run the risk of destroying the flywheel.

"OMG, an automatic? Why not just buy a moped and feel the wind in your vagina". Hey, I just might. I only live 2 miles from work, I'm sure the breezed will feel great!

Actually my drive train choice is a budgetary thing. I'd love to stick a manual box behind it, but motorcycle transmissions are expensive as fuck. Plus I want the motor facing forward. If anyone comes across a damn cheap transmission, post it, I'm not exactly saying no to the idea. Just the cost.


That's it for now, I'll post more when I start getting parts in!
 
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#5 ·
#11 ·





2003 Mazda6. Doesn't look like much on the outside, all the work is under the skin. 2.5 swap with mods, BC Racing coilovers, RX8 rims, over half the interior swapped, full led lighting other than high and low beams, lots of little details all over.

I ended up developing parts for this car that are now being used by many people to do the same motor swap. I sell several kits a month. From that kit, I've developed multiple versions to be used in other vehicles doing the same swap. I love making beer money!

I still have a ways to go on it. It's getting a manual swap, it needs body work, I need to finish the interior, and it'll eventually be boosted. I've done a lot of rebuilding on this car, and it is by far my favorite car of everything I've owned.

It also played a part in a recent even in my life :D
 
#16 ·
This project is right down my alley. I'm not a small person, but I like small, light, simple bikes. I've got a '67 BSA Lightning frame that someone hardtail'd and raked. I've got original, extended forks for it...external fork springs look cool as fook. I've been wishy washy about the whole thing, but reading your post has given me some motivation to just go for it. I've got an XL350 available to me....I think I'm gonna buy that Honda and toss the engine in to the Beezer.

Don't let this one die. I REALLY want to see this one all done up.
 
#17 ·
Ok. Possible change in forward lighting. TRS has the Morimoto Sealed7 LED V1 on closeout for 75 each. Thats low and high beams together. I really like the wide projector I have, but I wanna see all of creation......

Hoping to pick up the motor this weekend.
 
#24 ·
Powerplant change!

As much as I love the looks of the old Briggs in relation to this build, I struck a deal for something better suited. Sold my Cub Cadet 2166 to a fellow CF member a couple years ago. He's trading it back to me (somewhat). Powerplant will instead be a 16hp Kohler single with an electric pto, electric start, 15amp charging circuit, and best of all, oil pump with filter (kind of critical. The briggs was only a splash lube). I'm getting the engine, complete harness, PTO, everything I need to wire this in on the bike. Looks like I'm picking it up by this coming weekend!

After that, I get paid Monday, I'll see what I have left after bills. Hoping to go make an offer on that front end.
 
#28 ·
Ok, quick numbers change. Simply going up to 3600rpm brings me to a 105.51 top speed. This thing doesn't need to go near that fast.

Dropping front sprocket from 18 to 14, and leaving rear at 46 brings me to 3.29 ratio, with an 82.10 MPH top speed at 3600RPM.

I think these will be the new numbers to go with. I'm ok with losing theoretical top end. I want to make sure there's plenty of pull at lower speeds.
 
#31 ·
Is this boring yet? Hope not.

Making a change in the driveline, making it easier to keep the motor mounted how I want it, while also making the aesthetics a bit smoother. I realize that smoother looks is relative for a bike being powered by a tractor engine....


Ok, so I'm saying fuckit to the gearbox, torque converter, and chain drive. I'm gonna run a Noram 1800 centrifugal clutch with dual belts, and switching to shaft drive. This way I can keep everything inline, I can hang a shroud over the belts, and the bike has less visually moving parts.

If I don't like the engagement of the centrifugal, doesn't run the bike how I want at lower speeds, then I may switch out to a torque converter later. Not a big deal to leave myself some extra room to make the change later.

Shaft drive gives me a 3.18:1 rear gearing. With a 1:1 pulley ratio at 3800 rpm I'd be flying at 90. I suspect I'm gonna dial back to a 5.07inch pulley on the drive shaft with the 4 inch option on the clutch. This would take me down to 3000rpm output rpm, or down to about 70mph max. Plenty of speed for this thing, less work on the motor.

Picking up motor tomorrow, and hopefully the girder on Monday. Pics soon!
 
#32 ·


Quick and dirty. Set the Kohler down to see how it'll look. I need to cut off all the unnecessary tabs and mounts, and then weld in a piece of plate. Once I have the mount holes marked and drilled, I'll put support bars under it as well.

The Kohler takes more space than I thought it would, but that's ok. At 88 pounds the Kohler is still lighter than most bike motors I think. Gonna work on minimizing the frame this week. Also still hoping to pick up the girder tomorrow.
 
#34 ·
I can see those motors being equally light, or maybe even the smaller CB series as well. I just remember hefting my V45 motor, a 750 Shadow engine, and remembering those were a damn bit heavier. I can't imagine a Harley twin, inline triples/4s are any lighter either lol.


One of my goals with this is as lightweight as possible (though that will be offset by the fuel capacity), minimal hp (for a bike), and still capable of highway speeds (on the absolute top end. It's primarily gonna be for in town or county roads).

The engine weighs 88lbs. I'm not sure if they spec that empty or ready to run. Not that the quart or two of oil makes much difference.

I wanna run the Harley FatBob tanks so that I can run the speedo and all controls on the center panel. Fatbob tanks hold 5 gallons, plus the weight of the tanks, which if I'm to go off the tanks I used to have laying around, is somewhere in the range of 10lbs each side.

The Kohler runs a fuel pump, since the tractors it was used in ran tanks under the seat. I'm not gonna pull the pump or cap it off, instead I'll run a "reserve" tank in front of the back wheel. Should be good for another gallon, maybe two depending on how much space it ends up filling up. That tank too shouldn't be more than 5 lbs.

So as much as 7 gallons fuel, as much as 25lbs of fuel tank (and I'm severly overestimating here for the sake of weight estimates). We're looking at 69ish lbs. Plus engine at 88, we're at 157 or so.

What does anyone figure the average mag wheels weigh?

I'm going to run shaft drive, the rear dif is probably 20lbs. Rest of the swingarm is another 15ish? 35lbs. Rear drum brake assembly prolly another 15. 50lbs? 200lbs in running gear, plus wheels and frame.

My numbers are probably hella far off lol. I guess I'd like to see this bike come in at or under 350lbs wet. What do we think? Possible?
 
#37 ·
I got my numbers from a google search. Your numbers are only about 3/4 lb off the total I came up with. Either way is close enough for these estimates :D

I need to bring a table home soon so I can start the frame work. I have zero desire to be doing anything on the ground anymore. My machinist told me a good source for metal drops, I'm gonna run there and see what I can get for a piece of plate.

I gotta spend Saturday fixing a customers new riding mower, that outta give me some cash to throw at the bike.

I'm already planning out the electronics on the bike. On one hand, I can very easily run the entire bike off a modified version of the Cub Cadet wiring harness that came with the engine, plus a couple relays and extra circuits (bigger headlight, horn, high beam, etc).
But I also like how the M-Gadget setup looks. What I don't like is the MGadget pricing. Are there any lower cost alternatives? Or is the only locost alt making my own panel?
 
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