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CB-125T Page 01

This is a 1979 Honda CB125T.

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There are several reason why I went for the CB125T. First and foremost, it is the smallest displacement 4 stroke twin that was commercially available (as far as I know). It makes a bit more than double the power output of the Dream yet retains an almost identical wheelbase. The weight is close as well with the Dream weighing in at 80 kg and this at 125 kg. I reckon with some work I can get that number below 100 kg though. The rake and trail of the front end are surprisingly close as well.

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So in comparison to the Dream it is actually really close in size. It is a bit longer overall, but that is due to the huge tail light sticking out the back. It is also a bit wider and some of that can be attributed to the engine, but also the handlebars are quite wide as well. The seating position is much more upright so the bike feels larger than it really is. It looks much larger than the Dream in these shots.

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However, if you roll both the bikes up to the curb to line their front wheels up, you can see that the they are almost identical in length.

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So, since this thing was a rusty hunk, my first goal was to strip it right down. Which went surprisingly fast! As you can see here I got quite far on the first day (and this was starting at 15:00).

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Then I wanted to get the engine out so I did the "lay it on its side trick". That's where you lay the whole bike down, undo all the bolts holding the engine on, then lift the bike off the engine. It works surprisingly well!

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And, engine removed!

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Here's the now nearly empty frame.

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And a rather cool looking tag on the frame.

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My ultimate goal for this bike is to take the Dream front forks, brake, and wheel and graft it onto the CB125T. Then for the rear I want to take the Dream rear wheel and brake and run it in the CB125T rear swing arm. Then to complete the look, I'll use the Dream 50 seat and tank on the CB125T as well. I should end up with a bike that looks just like the Dream, but has a proper twin in it with double the power.

It should be fun!

Alright, so a lot of work has gone into the bike recently! First things first was to get an idea of how the seat and tank were going to sit, so I set them both on there and snapped a pic!

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There were some immediate problems with a bracket on the bottom of the tank hitting the bike frame. So, I removed that bracket and the tank got closer to fitting but I was having a serious issue with the fuel petcock. It needed to be in the same place as part of the frame.

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So, I sliced the frame a bit!

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This allowed me to set the tank on the frame properly and gave me a much closer mockup.

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The fuel petcock wasn't the only problem, the seat was banging into some brackets/braces on the frame as well. So, I sliced those up too.

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The front tank mounts, being designed for a completely different tank, were too far forward, too wide and a little too high. So, I had to cut those out and weld in new front tank mounts. Here's my super technical marking method: green tape.

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I used an M10 bolt and welded that in for the new rubber pieces to mount onto.

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Works pretty well!

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The tank is getting much closer to mounted. It looks like the front of the tank is sitting too low giving the tank a funky angle, but I measured the tank angle countless times and cross referenced it against the tank angle on the Dream 50 and they're within a half degree of each other.

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Next up was the rear tank mount. I had some thick 1 mm steel, but it wasn't very wide, and I needed a wide piece of steel. I solved this problem by welding together two pieces of 0.8 mm steel!

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It's plenty thick for what I need it to do.

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Here's the new mount welded into the bike.

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I welded a nut to the bottom as well so that the tank can be bolted down with ease.

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Rear of tank bolted down.

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Next was to get the seat mounted. This was a bit easier since the front of the seat just hooks under the tank mount. The rear of the seat required a bit of work, but these plates got the job done really well!

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The frame itself was causing problems though, as it was too long, not allowing the seat to sit flat. So, that was fixed by lopping the ends of the frame off!

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Everything bolted down!

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While I had the welder out, I decided to fix the frame where I had cut it earlier to make room for the petcock. I did this by taking the piece I cut out, bending it and running it at an angle to weld to the backbone.

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You can also see the plate I welded in over the bracket behind the tank mount.

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I test fit everything again and rolled it outside for some better pictures of the tank and seat alignment.

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I think it looks spot on!

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I gave it a test sit!

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Which inspired my girlfriend to sit on it too! The bike goes from looking like a tiny scooter bike under me to a full size bike under her, haha.

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Here's two more pictures of us sitting on it!

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And that's as far as I have come at the moment! It's been a blast working on this thing and it's moving along very nicely! A lot more fabrication work was required than I had initially thought, but it's turning out to be a lot of fun.


More on the Next Page!


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