WV Mountain Climber
I fabricated a custom swing arm and rear suspension for my Coleman CT200U-EX mini bike. I swapped the kick stand and created a mounting solution for a milk crate.
Transcript:
This is part two of my Coleman Mini Bike Build series. I wanted to share this clip again, just in case anyone missed it at the end of part 1.
This was one of those ideas you get that seem okay, until you start executing it, then you realize how bad of an idea it actually was.
This was the one and only time the bike rode in the back of the cavalier.
Mini Bike Swing Arm Fabrication
At any rate, here’s where things get fun with the bike. I decided to fabricate a swing arm and rear suspension. I had to make some compromises, but I’m glad I decided to move forward.
I used a Trailmaster MB200 as the inspiration for my swing arm. It seemed simple enough, and I decided to weld the diagonal frame piece before cutting the frame.
Everything looks good here, but that’s only because this is an edited photo. Here’s the * real* reason I took this photo.
I had stuck the extra welding glove over the air intake in hopes of preventing a fire… but that plan definitely failed.
When it lit up, I quickly ran to grab the fire extinguisher. The first two I grabbed were completely empty, but luckily the third one did the trick.
Existing Frame Modifications and Welding
I cut the frame apart and quickly ran into a problem I didn’t anticipate… It’s really hard to keep a wheel in place when it isn’t attached to anything. I clamped it up here just to keep it from falling over, and I got a little bit creative with my wheel chucks.
This is Corey, his Dad was once monetized on YouTube… many many years ago. He’s become saddened that his father hasn’t reach anywhere near 1,000 subscribers. Please consider subscribing to the channel. If you won’t do it for me… do it for Corey.
I found it was much easier to remove the wheel and just use the axle for reference. These jack stands came in handy for holding the frame body and figuring out the position for the swing arm.
Swing Arm / Rear Suspension Design
I welded some 1″ round tube to the swing arm to hold bearings, and I used a string to ensure the pivot point of the swing arm would line up with the jack-shaft.
This is something you definitely don’t want to overlook. If this is out of alignment, every time the swing arm moves, the chain will lose tension and want to jump off.
I used a piece of angle to tie the back of the frame together. It gave me a nice flat place to fabricate the shock mounting brackets.
This part of the process required a lot of sitting, thinking, and planning. I went with shocks that had both spring and air adjustments. And, I definitely lost count of how many times I moved the engine on and off during this process.
The other consideration was that, I didn’t want to raise the seat height of the bike. On steep and rocky terrain, I still wanted to be able to easily put my foot down and catch myself.
Mini Bike Exhaust Modification
Adding the rear suspension required me to move the street bike muffler into retirement. It was simply too large to support without a frame bracket.
To quiet the bike back down, I used the old header pipes to fabricate an extension to the stock exhaust.
I don’t have a tubing bender, so I simply cut pieces of the old header and welded them together. And yes, I ran out of hose clamps and had to use zip ties on the muffler… I expected them to melt off immediately, but somehow they’re still on there… I guess that’s a testament to the header wrap?
Additional Modifications
I also decided to swap the kickstand to the right-hand side of the bike. I extended it so I didn’t have to lean the bike over as far, and I moved it further back.
Also, take note that my milk crate is now magically attached. I over-engineered this part a little bit… but I got really tired of ratchet straps.
I didn’t have a tap and die set yet, so I drilled out the round tube and welded in some nuts. I used 10mm bolts to match the size of the driver pulley on the torque converter. This impact lives in a box of junk I bring for bike maintenance, so I always have a 10mm socket on it.
On the piece of flat bar, I offset my holes. It sits flush with the end of the rack for transportation, but when I attach the milk crate, I rotate it for a little more rigidity.
Also, this is my go-to outfit when I know I’m going to be outside in the sun. Props if you noticed my giant sun hat in the overhead shot.
That wraps up this video, make sure to like, share, comment with your favorite color, or anything else you do or don’t want to do in life. Thanks for watching.