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Tracker 10-21-2011 02:33 AM

Rokon TrailBreaker
Maybe a Nethercutt Trail-breaker?
About 4 years ago when I joined this forum, I put in my profile, "I want a Rokon Trailbreaker". Well, a couple hours ago I got one! As a side note- I found it a couple blocks from YZ Ernie's neighborhood. It will definitely be a project so I'll do a thread for anyone who might gain from my mistakes / etc. The only pic I have at this point is the one from the ad I responded to:
This should be fun. Yes, the engine in this Trailbreaker is from a Honda CA95 Benly.

Derekrm250 10-21-2011 06:01 AM

Awesome! btw how much does that thing weigh? :)

Tracker 10-21-2011 03:38 PM


Originally Posted by Derekrm250 (Post 638833)
Awesome! btw how much does that thing weigh? :)

I don't know what it weighs with this Honda twin street bike engine. It's leaving as soon as possible anyway. The advertized weight of a stock one is 210. They aren't as heavy as they look. The rims are hollow drums for hauling extra liquids.

memphis2857 10-21-2011 05:51 PM

Its hard to believe they still make those things. Apparently the U.S. Forest service has a whole fleet of them. They like the fact that they leave little or no footprint and the fact that they make a whole line of attachments and goodies for them. Rokon Trail-breaker Motorcycle

Mainjet2001 10-22-2011 10:51 PM

My dad had one of those and used it bunch in Colorado when he went hunting. He hauled a lot of deer & elk out of the mountains with it and a lot of his hunting buds used him to bring out their meat also.
I'm interested in your rebuid so keep us posted bud. ;)

Tracker 10-22-2011 11:27 PM

It should be a fun build. Of course I have a couple household projects to finish before I can really start. Once my "Domestic Credit Rating" is back in the black I'll tear into it.
This project will have a couple different rules than the last couple bike projects I did.
#1: nothing can be shiny
#2: a part or feature being "original" is of little important importance, outside of functionality.
#3: see number 1
I'll throw this out early: I'll be looking for a mid-eighties ATC 110 or 125 engine. I want a horizontal cylinder 4-stroke with cylinder head motor mounting lugs, a pull starter and a dual range tranny. If I'm really lucky I might find one in a semi intact chassis where I could use the whole engine cradle. We'll see.
I think I can get away with doing step 1 tomorrow. Step 1 is always the scads of pictures and notes I take before tear-down to increase my chances of getting it back together.

Tracker 11-12-2011 10:20 PM

Today I started. Since it doesn't have a kickstand I put it up on a basic moto stand and walked around it about 10 times. I kept asking myself "Where do I start?" and, "What did I get myself into?"
As I pondered how to get this Honda Dream engine out I realized there would be nothing to sit the bike on since the frame cradle was welded around the engine and had to be cut off.
Hmmm. First problem and I haven't started yet:hmm
OK. If I can't stand it on the ground I'll hang it from the rafter winch. It's actually kind of handy to be able to raise and lower the bike to whatever level you need to.
I made a few more laps as it hung there as I could see details much better.
Yup Handlebars by Schwinn. :confused
I bought a 10-pak of cut-off wheels for my angle grinder so tomorrow should be productive.:banana

neil_cox 11-13-2011 08:37 PM

Nice and good luck

Mainjet2001 11-13-2011 09:18 PM

We are watching Marty......:riding

Tracker 11-13-2011 09:40 PM


Originally Posted by Mainjet2001 (Post 640230)
We are watching Marty......:riding

A few friends, relatives, and co-workers wanted to follow along too so I sent them links to the page. More than one seems to think I have a thing for stuff that is old, weird, rusty, hopeless, and yellow.
:dunno I have no idea what they are talking about.

Mainjet2001 11-13-2011 09:49 PM


Originally Posted by Tracker (Post 640232)
A few friends, relatives, and co-workers wanted to follow along too so I sent them links to the page. More than one seems to think I have a thing for stuff that is old, weird, rusty, hopeless, and yellow.

:dunno I have no idea what they are talking about.

LOL.....Marty, that is because you and I are just like that old Greeves. :thumb

I'm going to get my body chrome plated because one of my old friends told me "if it doesn't go, chrome it". :surrender

Tracker 11-18-2011 11:32 PM
I thought I was going to get a lot of work done today but I was mistaken. My wife snapped this pic then unplugged my cord and said something about today being our 33rd anniversary.
There's always tomorrow I guess.

Tracker 11-21-2011 11:53 AM

I'm at a point with frame mods where I need the donor bike parts to go any further. No problem- There's still a lot more things that need to be dealt with, figured out, or cleaned up. These two parts are the front and rear "miter-boxes". They are the heart of the two wheel drive system. They are filled with gear lube and tend to leak if the seals aren't perfect. I want to be as leak-free as possible so I had to clean them up and figure out how to get them apart.
This is the front one. Old gear lube and desert dirt takes on some unique properties after a couple decades. Toward the left side is the u-joint that is at the steering pivot point. Ideally it would be in a sealed rubber boot and a whole lot greasier.
Here's the rear one cleaned up. The big sprocket on the right gets power from the engine and splits it two ways. The small sprocket on the left connects to the rear wheel and the shaft in the middle connects to a drive-shaft that runs in the frame backbone to that front miter-box.
Opening up these boxes takes a fairly specialized tool. I don't know what it is called, let alone have one. A one inch pipe union and a whole lot of filing gave me something I could put a pipe wrench on. All 6 ends came off and everything looks good inside. I'll replace the seals but the massive flat-roller bearings seem perfect.

Tracker 12-26-2011 08:23 PM

Things stalled on project Trail-breaker for a while. I had to deal with a blown engine in my truck ($5K),:hairraising go up north to fill a deer tag, and then the whole Christmas thing...... So, there wasn't a lot of time and money to spare. At about noon on Christmas day I found a few minutes to go out to the garage and make sparks. The frame on this thing was only made of mild steel and it had seen a bit of abuse, not to mention having someone go after it with a cutting torch to get the Honda Dream engine in there.
It would be an understatement to say it was a bit tweaked.
There was no convincing it to resume its original lines by brute or hydraulic force so I had to weaken it at key points to get things to move. After a few cuts I could move things where I wanted them and they would stay. Not having a frame jig I had to do my best with squares, levels, and stretched strings. I feel good about how straight I got it before tacking things back into place. I took my time about welding it up- constantly stopping to make sure the welding heat wasn't pushing anything out of whack.
I forgot to mention:I'm no engineer but I don't think it's a good thing when holes are drilled in tubes. Especially in the bend areas. I welded up 52 holes in the frame and forks. I'll be welding tabs wherever I want to bolt something to the frame.
In a couple places, like this rear rack loop, the holes were drilled at terrible places and major bending happened. Bending back and plugging the holes wouldn't work so I cut the tubes in half, hammered in round stock, then welded it all together.

Mainjet2001 12-26-2011 09:52 PM

Well Marty, you might not be an engineer but you sure do things correctly like one. You are also right about the drilled holes in tubing creating weakness.

Keep us posted my friend as we are watching..... ;)

Tracker 12-27-2011 12:31 AM

My luck may be swinging back toward the plus side: I finally got in touch with a guy selling an '85 Honda 125M ATC and I'm going out to look at it Tuesday AM.
As he looks for a crossed fingers emoticon..

ossagp 12-27-2011 01:12 AM

i have been unsuccessful on getting "my" greeves, and a man who had a rokon with a bad front drive and rust froze engine sold it to a guy who was a phone call ahead of me!!

Tracker 12-27-2011 10:37 AM


Originally Posted by ossagp (Post 642733)
i have been unsuccessful on getting "my" greeves, and a man who had a rokon with a bad front drive and rust froze engine sold it to a guy who was a phone call ahead of me!!

I've been in that position several times. With this Trailbreaker I got to be that other guy though. As the seller was helping me load it up her phone rang and I got to hear her say, "Sorry, it's leaving right now".
If you get a second shot at that Rokon, there's a guy on Ebay right now selling a front miter box. Those original Chrysler 2-stroke engines seem to be fairly common unless it was one of the real early ones that had a Maico industrial 2-stroke.

ossagp 12-27-2011 10:57 AM

this one apparently has the chrysler/west bend.

Tracker 12-27-2011 04:51 PM
:bananaAin't she a beaut?
I guess the beauty is in the eye of the beholder as they say. The morning putt across the desert to San Berdoo County paid off. It was just what I was looking for, and at the right price too. An interesting bit of irony is that the donor bike was found very close to where the Trail-Breaker was found.
As soon as chukar season closes things will progress rapidly. Archery chukar opens back up in mid-August and I've got a date with the boondocks.

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