Project: MTD

#1
I started with an MTD that seems like it spent it's retirement half in and half out of a tarp. The frame was split in two places and there was a major stress crack back near the rear axle mount. After input and suggestion on this board, I had mixed feeling as to either a) start hacking away and creating a Frankenstein bike, b) completely scrap the idea and start over with another bike, or c) repair the MTD and update it a bit with a different engine and tires.
After flopping around on the ideas like an eel in a frying pan, I chose "C".

I spliced a section of frame and ground and rewelded the splits. I'm comfortable that structurely, the bike is as good if not better then the day is rolled off the factory floor. The original Tecumseh is pretty much done. I plan on rebuilding it, but that will be during the dead of winter when I lose my ability to spray paint. I bought a clone from Harbor Freight and mod parts from Affordable Cart. The govenor has been removed, a new cam installed and 1.2-1 rockers and 17lb. springs. I also bought the header and air cleaner. I'm kicking around buying the Mikuni for it, but that might wait until I see how well it runs with the stock carb. It has a 40 tooth rear sprocket, so it should have some top end to it as well.

The original torque convertor is long gone, so I bought the driver for a the TAV 30 and will use the existing 30 driven clutch. I also fabricated a drag bar style handlebar for the bike. The original handlebars look like they were the first thing to touch the roadway after falling out of the back of a pick-up. They can be salvaged, but that will be a winter project also.

At this point, I have all the parts I need except for a few wheel bearing. New throttle, cables, brake band, new tires, new foot pegs, and all new hardware. I will replace all the bearings as well.
I guess I bored everyone enough, so here some photos to look at.
Thanks,
Larry


This is the way I bought it..

Rusted driver...the inside was pitted so bad that there were holes in the clutch housing.

Frame welded, sandblasted, and primed

New tires

Frame painted in a basecoat/urethane clearcoat. Homemade seat, and original fuel tank.

Drag bars with a touch of bondo to hide the welds. I have to finish sanding the bondo.

Clone engine. The blue gas tanks it on simply to bench test it. It will not be on the engine once it's installed on the bike.
 

delray

Well-Known Member
#2
Nitrohorse i think you will be the first here to install a clone honda style engine on a mtd/columbia frame:thumbsup:
:scooter:.................looking good
 
#3
Nitrohorse i think you will be the first here to install a clone honda style engine on a mtd/columbia frame:thumbsup:
:scooter:.................looking good
Now you have me concerned. I'm either going down a path that many have tried and failed, or I'm doing something very sacrilegious to mini bike affecinados.
In all seriousness, I'm still undecided as to which way I'll go with the TC.
SiInce there's already a jackshaft, I might mount the driven clutch on it and save myself the hassle of welding up the mounting holes on the TAV mounting plate and redrilling new holes. I'm the kind who will probably decide that at the last moment. I've been searching for a 5/8 threaded shaft with a keyway broached into it and have yet to find one. The original jackshaft is too short to install the driven clutch on it and also it's not threaded.
My last resort is to ues a 5/8 die and make some threads.
Your thoughts?
Thanks,
Larry
 
#5
Wow, I was never a big fan of thoughs bikes, but I think you have converted me over... Love it... Drag pipes will really change its look too.


Kelly
 
#6
Awesome paint...I'll bet it's even better than the camera can show.

Does that header clear the frame with that tilted engine mount plate?
Yellowhand,
There's alot more depth to the paint than the camera can pick up. I took a photo of the engine mount hoping to capture the depth, but it doesn't look like it did. You know, behind all these builds that us folks post on here is a world of "how am I going that fix that" or "shet, that won't work!". I've restored many a Wheel Horse garden tractors and it's all the same. I can admire anything that someone took the time to restore due to the amount of hours spent sandblasting, welding, painting, fabbing, etc.
Sorry for getting so winded..

The header will not fit in it's current configuration, so I will cut, weld, and bend till it does. I would like to have the header run along the bottom of the frame much like the Harley's do, but I think I'm going to have some real clearance issues. I'm hoping that the taller tires will allow for more room.
My idea was to make the bike "kind of" look like a drag or cafe style bike without altering the frame. I also was kicking round the idea of using header wrap and running the exhaust outside of the frame. My intentions are that anything I do to the bike can be returned to the original state.
Thanks,
Larry
 
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#7
Larry, can you hook that up direct drive, from the motor to the rear wheel? With that small sprocket, and that 6.5, it would be interesting to see if you could hold it down, and it should be real fast too!! That's if the chain don't dragg on the motor mount, you might even have to put on a pair of wheelie bars, Could you show a pic of the motor in there as it's suppose to be, I'd like to see how it looks, on that slanted motor mount, good luck with your build, the painting looks great so far.
dave
 
#9
Larry, can you hook that up direct drive, from the motor to the rear wheel? With that small sprocket, and that 6.5, it would be interesting to see if you could hold it down, and it should be real fast too!! That's if the chain don't dragg on the motor mount, you might even have to put on a pair of wheelie bars, Could you show a pic of the motor in there as it's suppose to be, I'd like to see how it looks, on that slanted motor mount, good luck with your build, the painting looks great so far.
dave
Dave,
I want to stay with the TC. I want speed and the ability to climb a hill. I was looking at the back of the bike for a place to mount wheelie bars if needed.
There's two pre-drilled holes back there that would work if I need them.
I'll post a photo of the engine on the mount once I get that far.
Larry
 
#12
Well, my Saturday plan of painting the forks and handlebars was puxhed off to Suunday thanks to the heavy rains of Tropical Storm Hannah. It was so wet and humid Saturday that the primer did not want to dry properly inside the garage.
I finished cleaning up the welds and did the paint and clear Sunday.
Here's a few pictures of the handlebars and forks attached to the bike. I need to purchase some additional hardware as I want to make fork stops to prevent the top tree from hitting the upper frame.
Larry

Front View

Side View

Forks

I thought hiding the welds turned out ok..
 
#13
Well, my progress has been slowed due to being bitten on the right hand by my neighbor's dog. It's hard working with 1 1/2 hands. I have a feeling that I'm not going to make much head way until the 15 stitches in my hand are removed.
Anyhow, I did manage to set the engine on the mount. I'm going to have a major job ahead trying to keep the header inside of the frame rails. We'll see what happens once I start bending the header pipes. The air cleaner also protrudes out of the right side, but that I can live with since bumping it will not result in scar tissue. I might try my hand at fabbing something to straighten out the intake runner.
It hard to type with one hand, so here's some photos.
Let me know what you think.
Thanks,
Larry




 
#14
I have a MTD Trailflight I'm fixin to redo which also has the angled motor plate in which I wanted to get a HF clone.After seeing this my question was answered without even asking,thanks.The performance parts are they aftermarket or O.E.M. Honda?Nice job molding those joints allways puts a touch on things.:thumbsup:
 
#15
COOP,
All the parts in and on the engine are aftermarket. I order a Mikuni and intake for the engine and then I'm done with the engine. I went to assemble the rear tire and axle to the bike today and found out that the new tire (and tube) was flat. It's a split rim and I have a feeling that the tube was pinched somehow. I was damn careful assembling it, but Murphy and his law must have been active that day. So it's disassemble the rear tire and find the cause.
I use to work in a body shop many, many years ago and still have a very few of the skills left. It's more of "how much time do you want to spend on it" than it is ability with most of us on these projects. I guess it's personal preference, but I always liked hiding the welds when possible.

I seen you have an MTD and are interested in a clone. The biggest hurdle I can see is trying to tuck the entire header under the frame. I doubt all of it will be under, but I plan on using some header wrap for the few inches that will stick out near the engine. I'll see how it goes once I tackle that part of the build. TO get all the pipe from the exhaust manifold back inside of the frame would require a very tight radius bend right off the engine. I'm not looking to set any land speed records, but I have concerns that the steep radius will create too much back pressure and flow issues.
Larry
 
#18
Got to do a little mini work today. The process is dragging along until I can get the stitches out of my hand this coming Friday. It's a little rough trying to work with 1 1/2 hands..
I got the Mikuni installed and the throttle cable. I also got the TC fabbed up and will finish that Monday after work. I'm trying to decide if I want to mount the driven sheave on the jackshaft or keep it on the Comet mount. I have 5/8" stock with a keyway broached in it, so all I have to do is add threads to one end.
I also decided I needed steering stops after the triple tree put a gouge in the paint on the frame.
Anyhow, here's some pics of the slow progress...



 
#19
Nitro, where'd you get the broached 5/8" jackshaft from? I'd like to replace the one on my Cheetah as it could be a little longer.

That there's a nice lookin' mosheen you gots there.
 
#20
KD,
Thank you sir...
I had the shaft made by a neighbor who fomerly worked for Ford.
But you can buy new shafts from BMI Karting. And they're a hell of alot cheaper than paying a machine shop to broach a keyway. The price is $12.95 for a 16" shaft. I kinda like the look of the TAV using a jackshaft.
Here's the site:
BMI Karts and Supplies - Home

The shaft is listed under Kart/Mini Bike parts down towards the bottom right of the page.
Nitro
 
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