MT250 Knobby Vintage Streetfighting Cafe Scrambling Rat Tracker

I finally decided I had done enough to my project to begin a thread.

First off, I want to set the stage for this build, and declare a bit of purpose and direction.

I'm a confessed tinkerer, and find that I usually enjoy projects more than having the completed product. Over the last year I have been helping a friend, Luke, build a CB650 into a worthy desert race bike for the Mexican 1000. (http://advrider.com/forums/showthread.php?t=823952). I watched as his build unfolded - every deviation from the stock design created a problem and required a solution, which is what I really like about projects. After I went to the The One Motorcycle Show (www.the1moto.com) this winter in Portland, I was hooked on the idea of making my own bike.

I decided that I would make my vision of the quintessential motorcycle. After watching Luke make all variety of unrelated parts come together into a killer bike, I established one key approach to my build: Collect individual parts that represent the essence of motorcycle. Put them all in the same room. Move them closer and closer together, until they form a motorcycle.

So that's the plan. I look forward to other's thoughts on my project.

Re: MT250 Knobby Vintage Streetfighting Cafe Scrambling Rat Bike

So that said, here's what I like:

Knobby tires
Fat front tires
Adventure bikes
Old Hondas
Bare Metal
Things that aren't made out of plastic
Rube Goldberg
Two strokes
Anodized shit
Re-purposing household things into motorcycle parts
Black rims
Upside down forks
License Plates
Things that aren't half-assed
Carbon fiber
Ugly ducklings and under dogs
Things that are simple
Things that are complicated
Steampunk

Re: MT250 Knobby Vintage Streetfighting Cafe Scrambling Rat Bike

$400 on Craigslist:


Barn-found 1974 Honda MT250 Elsinore

Re: MT250 Knobby Vintage Streetfighting Cafe Scrambling Rat Bike

The current owner had purchased it at an estate sale about a month ago. It had 257 miles on the odometer, but it was also disconnected. So who knows how much action it's actually seen. At any rate the current owner couldn't get any spark, and he was done trying to figure it out. A quick inspection revealed that it was entirely intact - even the cool tool box under the seat was there with all the original tools.

Re: MT250 Knobby Vintage Streetfighting Cafe Scrambling Rat Bike

Here's the other side of the bike. These photos will later be referred to as "before."

Re: MT250 Knobby Vintage Streetfighting Cafe Scrambling Rat Bike

When I dragged the new bike home, I sat down at the computer to see what other people had already done with this bike. After wandering cyberspace, I found that very few people had done much with this particular model. The few that had (no disrespect intended), seemed like they had not tapped into the novelty of a street-legal, two-stroke, vintage dual-sport bike.

All this seemed perfect, because before finding this bike one of my biggest concerns was that I was just going to copy other people's ideas. As much as possible, I didn't want to steal anybody else's solutions to problems or copy anyone else's designs. I've done that in the past and have the highest regards for the creativity of others, but I wanted to be able to say that I made my own bike.

That said, I also began collecting pieces of inspiration. I'll include some here as well as along the way as I find more.

Re: MT250 Knobby Vintage Streetfighting Cafe Scrambling Rat Bike

More:

Re: MT250 Knobby Vintage Streetfighting Cafe Scrambling Rat Bike

More:

Elsinore gets its first bath.

First order of business was to see what was lurking under all the plastic and the big fluffy seat.

Re: MT250 Knobby Vintage Streetfighting Cafe Scrambling Rat Bike

There are a fair amount of custom Elsinores out there - very cool platform to start with, and they are a ton of fun. I'm in.

Re: MT250 Knobby Vintage Streetfighting Cafe Scrambling Rat Bike

Looking pretty good after a scrub. I'd say you got a pretty fair deal for a mere $400. i love the tanks on the old MTs.

I followed your Desert Sled build with Luke and thought it was fantastic. Hated to see the it end that way but I'm sure that bike has some more race left in it.

Subscribed.

Re: MT250 Knobby Vintage Streetfighting Cafe Scrambling Rat Bike

After staring at the bike for hours, following one wire at a time to its individual end point, I still couldn't figure out why it didn't have spark. So I just started replacing things. First the spark plug - still nothing. Then the coil - nothing. Then the points and voila... It sprang to life. The bike had not been registered since 1975, and secretly I like to think that it hasn't run since then...

http://www.youtube.com/watch?v=2FDc10OivFo

The smoke detector celebrated my accomplishment!

Re: MT250 Knobby Vintage Streetfighting Cafe Scrambling Rat Bike

I took it for a spin around the neighborhood and was pretty stoked that it seemed to move right along. I got a little feel of what the bike would do, and after a couple laps I knew what this bike would be. It's not going to "do the ton," and that's actually fine by me. I have a faithful BMW F650gs that is great for long hauls and KTM 525EXC that is eager to tear my arms off if I don't keep it under wraps. What my stable is missing it a back-alley bike. A bike for ripping around town. It doesn't need to tear down the freeway. It needs to rattle down pot-holed Portland streets and explore some gravel roads in the Oregon Coast Range. And of course it needs to embody something that the BMW and KTM don't: It needs some soul.

There are alot of different names for the the sub-categories of custom motorcycles, and I appreciate small pieces of almost all these categories. But when I try to imagine what I'm trying to make it just doesn't seem to fit any of them perfectly. It needs to be somewhat of a street fighter, but with elements of a cafe racer. It's got vintage DNA, but needs a breath of modern technology. It's going to be somewhat of a rat bike, but buffed out a little more than pure rat bikes.

In the end, I started thinking of it as "Scrapper". That terms conjures up the image of a little fighter, maybe even a bit of a dirty fighter. Sort of a loud-mouth that's a little rough around the edges, but one that can back up its bark with a little bite. And of course, the reference to scraps, which is what I intend to use as the primary building blocks.

So, say hello to the beginning of the Elsinore Scrapper

Re: MT250 Knobby Vintage Streetfighting Cafe Scrambling Rat Bike

I didn't know anything about this bike before I bought it, but here's what I learned.

The 1974 Honda Elsinore MT250 was the enduro version of the much more popular CR250 dirt bike. The CR had a solid following including Steve McQueen. The MT differed in a few key ways.

1) The MT has 20 pounds or so of street legal lights, all of which are pretty visually offensive from my perspective, especially the rear tail light thing.
2) The MT had an enormous air box contraption under the seat.
3) The MT has a different cylinder, piston, and head that make it a bit more mellow than the CR.
4) The MT injects oil from a reservoir under the seat directly into the manifold between the carb and the cylinder.
5) The CR runs its exhaust under the frame, while the MT has it on the right side up high like a scrambler.

But once I got the Scrapper running, it was time to gut it.

Had to go:



Here's a look at the air box after the enormous exhaust came off.



The other side with the oil reservoir.

Re: MT250 Knobby Vintage Streetfighting Cafe Scrambling Rat Bike

At first, I was just going to tear every last bit of all that crap under the seat out. I was going to go with a pod filter and mix my own gas/oil to ditch the oil injector/reservoir operation. That would clear out the section under the seat, but then I decided that the whole mixes-its-own-oil thing was actually pretty cool. What was not "pretty cool" was that enormous milk-jug-looking reservoir. So I decided to go ahead with a pod filter, but make an oil reservoir that was less offensive than the stock plastic deal.

I scrounged around the basement looking for some inspiration and found a MSR backpacking stove fuel bottle. It looked like it was just about the size to fit under the seat and worthy of holding oil. I hit it with the wire wheel to get it down to bare metal and fitted it with some brass fittings.

Re: MT250 Knobby Vintage Streetfighting Cafe Scrambling Rat Bike

It mounted up pretty well, and I ran tubing all the way to the back fender where I drilled a hole and created a fitting to fill the tank from the fender.





But this first attempt at a reservoir was a failure. The fittings leaked and the rear tire fouled the filler tube at full compression. So I had to move on to version 2. The fittings on the MSR bottle were just threaded through a really thin aluminum wall and JB welded into place. They leaked and when I looked at it more and more it was sort of half-assed. Maybe even only a third-assed. So I reluctantly started over, and as in past similar scenarios, the second version was way better.

This time I found a stainless steel coffee mug that had a lid I could unscrew to reach inside. This meant that I could drill a hole through the sidewall (which was double thickness this time because the cup is a vaccuum style) and sneak a wrench inside to tighten a nut on end of the threaded brass fittings. So I was able to tighten everything down and even thow some rubber washers on both sides to keep it from leaking. I also bagged the idea of having the reservoir fill from a fitting in the rear fender. Instead the filler is a 90-degree fitting that is accessed after opening the seat.

Re: MT250 Knobby Vintage Streetfighting Cafe Scrambling Rat Bike

Found these on Ebay and in the spirit of just collecting things that I like, and slowly moving them closer together until they become a motorcycle, I snagged them. I knew when I bought them that they'd be sprung/dampened incorrectly, but I sort of relished the opportunity to take them apart, calculate what needed to change and modify them appropriately.

Re: MT250 Knobby Vintage Streetfighting Cafe Scrambling Rat Bike

Wowzers. Going to be following this one!

Re: MT250 Knobby Vintage Streetfighting Cafe Scrambling Rat Bike

Sure enough when I put the shocks on, they were way too stiff. I schlepped them off to a local suspension guru and we measured the spring rate of the stock shocks. I just need to source the appropriate spring size/rate. But once I had the new shocks on the bike, the fork had to go.

This was actually the step that I was most looking forward to when I started the project. I've never really liked the way vintage dirt bikes looked, and when I sorted out why it was two things: the forks/front-wheel looked way too wimpy and the seat was fat and just plain ugly. I have plans for the seat, but I began the process of finding an appropriate fork.

I knew that I wanted a big, chunky front tire. In fact, I knew I wanted an 18-inch TKC80. I have used these almost excluisively on my BMW and they are awesome. They stick to asphalt and match a big dual-sport bikes offroad abilities. That is to say that these big bikes are not meant to be in off road conditions that would require more tire than that, and any tire less aggressive than that off road handicaps these bikes even more.

Additionally, I wanted the bike to retain some of its original geometry. I knew that in all likelihood, I'd find a shorter fork than stock, and the smaller wheel would also bring the front end down, steepening the head tube angle. But I tried my best to find a fork that was as close to stock as possible. There are great fork comparison tables on www.customfighters.com, and after sifting through the data on these tables, I determined that the 1991 GSXR 1100 had the longest USD fork of any street bike. Although I mentioned above that I wanted to solve as many problems independently as possible, I did see that there was a lot of information available about Harley Narrow Glide wheels in GSXR forks.

I found a fork and other front end pieces on Ebay, and ordered a ball bearing conversion kit from All Balls Racing.



Mocked up with a knobby tire...

One of the reasons I like two-strokes is pipe. I love the obvious handcraftsmanship in a nice pipe. That's why the stock POS was such a disappointment. Once I took it off, I couldn't put it back on. I ordered this pipe from PFR, and it turned out just the way I had hoped.