1977 Mugen 125 # 12 Steve Wise replica build

Bluelion
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Well here I go again just finished a 1979 Mugen air cooled 125 build. I am jumping right into this build. It’s going to be a 1977 air cooled 125 Mugen. It will be an exact replica of the bike that Cliff White built for Steve Wise to race the 125 nationals.

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Bluelion
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3/10/2026 8:07am

I picked up the 1977 Honda CR125M Elsinore in Ohio as a donor Bike for this build.

2C2FD4DC-BC9C-49E9-A2C1-F8449B26C88F.jpeg?VersionId=qQ QL.EeDv71.
 

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Bluelion
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3/10/2026 8:08am
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Bluelion
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3/10/2026 8:10am

I do have most of the parts already gathered up and purchased for this build. Even the MugenBB81457A-2BE9-4005-8A5E-4C1730CFE794.jpeg?VersionId=9FaV3uhWf9fNGM9tTi0Vc engine kit. Pipe airbox and silencer.

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Bluelion
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3/10/2026 8:13am
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The Shop

Bluelion
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Bluelion
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3/10/2026 8:16am
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Bluelion
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3/10/2026 8:18am

I also have the suspension components, Siimons forks. Fox AirShox. And Thor swingarm.

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Bluelion
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Bluelion
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3/10/2026 8:21am

I’m trying to hand make a chain tensor to match the one that was on Steve’s bike.. it is still a work in progress.

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Bluelion
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3/10/2026 8:24am

Stay tuned. Much more to come. I will start taking apart the donor bike this week.

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Bluelion
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3/11/2026 4:27am

I got the bike hung up last night to start the disassembly process.

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Bluelion
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3/11/2026 4:28am
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Bluelion
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SCYRacing
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3/11/2026 9:26am

I wonder if the lone down voter hates you or Mugen/Hondas?🤣

Anyway looking forward to your next build!

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Bluelion
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3/12/2026 3:23am
SCYRacing wrote:

I wonder if the lone down voter hates you or Mugen/Hondas?🤣

Anyway looking forward to your next build!

Get away from the mugen’s! He hates these mugen’s!!!

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kijen
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3/12/2026 4:39am

Dream build right there for me.

As a kid i siezed my 77, just learning maintence at the time and not much money, went to motorcycle junkyard looking for a cylinder, guy said no 125 cylinders, but recommended a mr175 cyl, head  he had and its a direct fit, so got that and a piston. I was mainly riding the dez so it worked out great.

3/12/2026 7:19am
SCYRacing wrote:

I wonder if the lone down voter hates you or Mugen/Hondas?🤣

Anyway looking forward to your next build!

I'm new here and one of the fist things I noticed are random downvotes on benign posts. I was thinking they were on accident maybe.

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Bluelion
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3/17/2026 3:18am

Working on getting the doner bike apart. It’s been going out little slow because I’ve had so much going on lately.
906C4309-5E01-44C5-BC4C-9555CA22B5EA 

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3/17/2026 1:45pm

How much of the donor will you actually use? Frame, tank, seat, bottom end?

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Bluelion
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3/18/2026 3:05am
Shredder wrote:

How much of the donor will you actually use? Frame, tank, seat, bottom end?

Frame, tank, seat, wheels, handle bars, controls, and other misc small parts.

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Bluelion
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3/18/2026 3:26am

So I got the Doner bike completely taken apart. I’m really happy with the bones of this bike. A lot of the bike seemed like It never had a wrench on it. A good solid bike to start with. A lot of the parts that I don’t need will be for sale.
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Bluelion
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Bluelion
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Bluelion
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3/18/2026 3:36am
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Bluelion
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3/18/2026 3:39am

Just to get an idea before I’m at with the rear suspension? I went ahead and mocked up the Thor swingarm and Fox Shox. I will have to move the upper shock mount and modify the frame to replicate the real bike.
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Bluelion
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Bluelion
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3/18/2026 3:42am

I have now realized that I need a completely different steering stem to install the Simons fork clamps. Does anybody out there know of a steering stem for the Simons forks for this model and year that I could buy? 

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PN27416
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3/20/2026 1:39pm
Bluelion wrote:
I have now realized that I need a completely different steering stem to install the Simons fork clamps. Does anybody out there know of a steering...

I have now realized that I need a completely different steering stem to install the Simons fork clamps. Does anybody out there know of a steering stem for the Simons forks for this model and year that I could buy? 

 When I put Simons of my Steve Wise Fox RM370 replica I pressed the stock stem from the stock triple lower then made a sleeve if I recall to fit it to the Simons triples.

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PN27416
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3/20/2026 1:43pm
Bluelion wrote:
I’m trying to hand make a chain tensor to match the one that was on Steve’s bike.. it is still a work in progress.

I’m trying to hand make a chain tensor to match the one that was on Steve’s bike.. it is still a work in progress.

3FA64F18-4406-4F31-A699-B66861523493.jpeg?VersionId=5qBCVWEA5CA7BB-F40B-45E6-B5B8-6C2014EE8BBE

Take a look at the Pro tec replicas on ebay. Search "vintage pro tec" He may have what your after or something close you can modify

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