Posts
1270
Joined
9/10/2013
Location
Lafayette, IN, USA
1979 Mugen air cooled ME125RZ Restoration
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One of the first things that I will have to address is the broken fins from the bike falling over.🤦🏻
79's can be made into beautiful bikes.
Yes they can. One of my favorite years of the Honda 125.
Started the tear down process. The engine was worse than I thought. 🥴![]()
But I will be able to fix it. I have a spare 1979 CR that has everything I need.
The piston was stuck, but I was able to free it up and get it out without damage.
So the first thing on the cylinder I wanted to address was the broken fins.
The first thing to do was to clean the cylinder really good. Then sandblast it to get it really clean for welding. Then a friend of mine had a junk donor yamaha blaster cylinder that we were able to cut fins off of with a bandsaw. Then the donor fins were shaped to fit the broken area of the mugen cylinder.
Pit Row
That bottom end gave me the "er mer gerds"!
They are Kayaba shocks, aren't they?
You probably already know, but Thor Lawson offers manuals, and Seal kits etc for them :
http://www.evolutionsuspensionproducts.com/
Yes, I am aware Thor Lawsons website.
Next is the difficult welding process. The people out there that know how difficult it is to weld cast aluminum would understand what I’m talking about. But I was able to get it welded and shaped up pretty nice. I’m pretty happy with the result.
Very interested to see if you restore the KYB shocks or switch to another set. I have a few pair that are really not gold colored any more and hope you decide to make them gold again!
The KYB shocks will not be going back on this build. Neither will the DG swingarm. I will be putting a Thor swing arm on it with Fox air shocks. And Simmons forks.
Just as an FYI for anyone who is interested? This is the difference between the stock 79 CR 125R silencer and the 1979 Mugen 125RZ silencer. The Mugen silencer is on the right and is the slightly rustier one.
And here is the difference between the expansion chamber/ exhaust pipe.
The frame and other miscellaneous parts are back from the sand blaster. I and going to modify this frame to accept the 21in front wheel.
Pipe is sandblasted, repaired and painted.
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