Scary Tubes

I starting taking apart the fork tubes, first the gaters, then the springs. One tube looks very nice, but I'll show you the other one here.

I need to smooth out these fork tubes if I ever want to have good oil seals. Very tempting to just buy a new fork tube on ebay for about $60, but that's what I've spent already on the whole thing! That would mean the forks would cost $120.

So I'm stuck with these. I found a post on a forum about repairing these things.

You can see it here:
http://www.venturerider.org/forum/showthread.php?t=7833

1,000 Hand Slap

I had a feeling that I should dismantle the CT90 forks and make sure they are in real working order. I think squishing them with my hands is not a good test.

Here they are, ready to be dismantled. I didn't look up how to do it, and it seemed that my method was not very good. I took out the bolts on the triple tree that hold the fork tubes and pounded on the top of the tubes with a mallet whilst holding the tree steady in my left hand. I couldn't set them on the floor, since I didn't want to damage it.

One of the tubes had some rust, and I was glad that I decided to take these things apart, but very frustrated with my technique. The distance you see between the gater and triple tree was as far as I could pound the tube after a few hundred slaps with the mallet. At this point I started to count.

This was a stupid idea... put top brace over the bolt and hammer down on it. I don't know what I was thinking, but maybe the idea was to create more surface area to pound on. 

In this picture you can see how I was holding it with my left hand, and also the progress after 1,000+ mallet slaps. My hammer arm was getting pretty warmed up by then. 

Almost done! What kept me going was the way I could tell that I was making progress, even if slow! This was about 1,400+ slaps. 

VICTORY! 

I don't think there was really anything wrong with my technique. It was required actually. The tubes are supposed to slip right out, but some crusty rust was preventing this on this tube.

However, I think I should have waited a few hours after loosening the triple tree clamps; the other fork tube fell right out the next morning. Maybe the metal took a while to relax after being clenched for so long. Could it have made this tube come out easier? I'll never know...

Here are the casualties: 

 Oh no! Not my mallet! My most useful tool!

There is no way I am going to spend $3 on a new mallet. 

My left thumb was also a casualty. Holding the triple tree steady for so long was not good for that thumb. Of course, it only felt painful after letting go of the thing. An hour of video gaming later and it was fine. 

Besides, hurting yourself while building a motorcycle just makes you more badass and manly, right? 

I will try restore the fork tubes next! 

Z50 Carburetor Mysteries

I haven't said anything about it, but the carburetor that came with the z50 has been confusing me for a few months now. I want to test the engine, but I have no idea if this carb could really do that. I've looked at many z50s, and I haven't seen a carb like it. It was also bolted on redneck style, since the threads are stripped. It has a gasket, which is also redneck style.

Here it is, after a lot of cleaning of course. When I took it apart, it looked very different from carbs I've seen (I haven't seen very many at all to be honest). I couldn't find any rebuild kits on ebay that looked similar to what I had at all, especially that lopsided circular, float bowl seal.

The main jet (or what I'm assuming to be the main jet) is also very strange and drops out easily if I whack the carb. It seems like half of what I need. It is clean though; I can see daylight through all of its passages.

Here is the float need on the left. The float needle from my C70 is on the right. There is no notch on the Z50 carb float needle that attaches to the float... the parts of this carb are so minimalist! I tested it though, and it works by gravity alone.











All of this said, I asked about it on a few small Honda groups and they assured me that I have everything I need to have a working carburetor. Very interesting indeed.

17" wheels

Got some wheels finally! Had to get them at the post office and tie them to my C70 to get them home... god the United Postal Service is a piece of crap. I won't complain any more than that it took 1 hour for no reason. I ended up getting 3 wheels. I saw 2 wheels that were fine, but then I saw another CT90 rear wheel for 1 dollar! I kind of feel bad for the seller... But here they are! The front wheel seemed like it had a nice tire so I took it down the street to pump it up and whaddya know! It holds air! Well, I can use it for testing and also know that I have a good tube to work with. The third wheel is not pictured... too boring.

Swingarm Troubles

Shortly following the good news about the CT90 fork, I ran into some trouble with the C70 swingarm I already had.

The C70 swingarm does match the CL70 frame width and bolts to it quite nicely. I thought I had won.

However, the curved cross brace prevents much suspension travel. Not enough I would think, unless I had really long shocks, and I am not looking to build a dirtbike.

So I quickly got on ebay and bought a CL70 swingarm. It should work, right? Besides, it was only $10. It's in really bad shape cosmetically. Seems to have about the same travel before the cross brace hits the frame... hmmmm... maybe this is not an issue at all. I'd rather use the C70 swingarm, but they both kind of suck... I will be looking at more swingarms to see what else fits.

IT DOES FIT! (the CT90 fork does)

I got the CL70 frame finally! I had an appointment that night, but I couldn't wait and went straight to my closet to see if the fork fits into the CL70 frame. Awesome! Seems like they were made for each other! And what about the C70 Passport swingarm I have? We'll see next post!

Fork Choice

I've been spending way too much time researching forks. There are a lot of measurements on these things... I very much hope I got something that will fit.

What I chose was a CT90 hydraulic fork; there it is on the left.
It was only $60 shipped and came with the handlebar clamp. The headlight ears were bent a little, I bent them back. One of the cool black gaters has a tear in it as well, which seems fine. I pushed on them and they seem to work alright. I'll have to wait for the frame to come to see if they fit into them.

More Spending

I ordered some stuff for this project.

A CL 70 frame! 

After tons of research and indecision, I chose this frame. It should give me good leg  room, while being short from front to back. It also has good ground clearance for smaller wheels. The CL 70 is also a very light bike; 150 pounds! The C70 and S65 frames look nice, but they have that metal rear fender and thicker middle which I'm sure adds some weight. I could cut those off, but I don't want to ruin anything that someone might have wanted to use in its stock form. Finally, this was the cheapest frame on Ebay at just 50 bucks!

I hope my C70 swing arm works with this frame. I will also be checking if the fork tube from the Z50 will fit. From this chart, it says it will. I also have an option of putting in the ct90 full fork. Lots of options really…

http://www.clubchopper.com/forums/showthread.php?t=77043

Choosing a fork is very scary. I don't fully understand what these numbers mean. Again, I don't know much about building bikes! I guess if the bikes are in the same lists, then they will interchange, or at least the diameters of the tubes are. 

I also ordered a ct90 head. I thought this would be good for an 85cc upgrade that I'd like to do later. After looking at the kits, they say to use the Z50 head though… maybe it was a waste of money. 

Prices:

CT90 Head :: $24.99

CL70 Frame:: $49.99

Shipping:: $50.00

Total :: - 124.98

Total Expenses so far:

$324.98


Ah, and here is a nice picture of my C70.

Re-Assemble!

After reading the shop manual, I had the idea that I needed flywheel puller to get this engine timed right. Here's the shop manual:

http://autos.groups.yahoo.com/group/hondaminitrailandmonkeyclub/files/

Join this group to download it.

But actually, thanks to "Alex the Man", this engine was designed very nicely so that I need not take off the flywheel. So I will follow this video:

http://www.youtube.com/watch?v=_2xRnGlqzeA

Everything should apply perfectly, I just have a much dirtier engine. I'm sure I will be using many of this videos for this project. I recommend subscribing to his channel. He mentions in one of his comments that the Honda engines have a wasted spark ignition, so it sparks every time at top dead center. That's pretty cool. Makes everything easier to work with.

Ah, I had to make a makeshift gasket for the cam cover; the old one flaked away and would definitely not be holding any oil in. I read somewhere that you could use a cereal box as a gasket...

This might work for testing purposes... But if it holds oil for more than that, I will leave it! And here it is, going back into the cruddy frame. It kinds of makes me feel like it will work... probably not. Oh, and you can see my choices in reading here... not interested in American Labor History though, it was just a textbook for an online summer class that I failed. DON'T TAKE ONLINE CLASSES. They waste your money.

Stupid Disassembly

I took the head off for pretty much no reason. I suppose I wanted to see if the piston was feeling alright, but it was obvious from the start that it was. And it looks good. I cleaned some more things up, but I shouldn't have done this. The cylinder won't come off for some reason. Also, there are some collars on 2 of the 4 head studs. Did I lose the other 2? 

Ah I found out:

http://dratv.com/guidepin8x14.html

I only need 2. Strange. I will reassemble the engine next and build a new wiring harness.

Cleaning Up the Z50

This Z50 is super greasy and muddy. The gastank smells like varnish. Everything will need a good cleaning. I have no power tools so this will all be by hand and brush. 

I have a bucket, a brush, a few rags, Windex, baking soda, and some very weak carb cleaner. These are the results.

The carburetor seems to be clean now and should work. Probably lost a few braincells breathing in that carb cleaner spray...

Starting Point

Starting Point:

I stupidly bought a supremely messed up Honda c70 a while back, thinking I could fix it up. It looked okay, but in reality it was one of the most thoroughly damaged bikes in the universe. A group of karate masters had certainly practiced on this thing and then chucked it into the Sahara desert from a high flying cargo plane. 

But this is what I could salvage:

-Exhaust Pipe (kinda rusty)

-Front fender (cracked but fixable)

-A frozen carburetor

-Intake Tubing

-Front shocks

-Choke and Speedometer cables

-Rear cargo rack

-C70 handlebars 

-Gas tank and seat bracket

-Random nuts and bolts

The frame, trashed engine, fork, and wheels were stolen by the roving Mexican junk collector trucks. The frame and front fork were still good. Damnit!

Most of this will be useless on the new bike, except the exhaust pipe and possibly the shocks and cables. I want to try and use the plastic fender somehow as well. I'm imagining doing a frankenstein fix on it by sewing up the crack by drilling small holes and tying it up with fishing wire, then melting it a bit. Just a theory. 

As I said, I was planning to fix this c70, so I bought some stuff it needed. This stuff is all in good condition:

-Rear swingarm, faded red

-C70 solo seat

-Chain guards 

With both of these boxes of parts, you might get 1/6th of a bike. I was too lazy to sell all of this, so I bought another parts bike.

1973 Honda Z50 in very muddy condition. It had been sitting for 5 years. It was in the Suburbs and cost $200 total for the bike and shipping to my place. It looked like crap, but I'm discovering that it wasn't such a bad deal. 

My first expense for this project. 

- $200

I would say that most of the parts on this bike are usable. The engine is certainly in good shape and seems like it almost wants to start. I can tell by the sound that it's got good compression. I've kicked it over a few times and it sounds like the compression is good, has a nice "plowp-plowp" sort of sound to it, and I can feel puffs of air coming from the exhaust. 

The wiring looks very messed up so I'm assuming it's not getting spark. I'm sure the carburetor is very dirty as well. 

These are the parts I certainly want to keep for the build:

-50cc engine

-Carburetor

-Any random bolts I need

Here are some other parts that MIGHT fit on the new build:

-Front and rear brake hubs

-Front fork triple tree (it seems very sturdy, perhaps I could put in some longer legs?)

-Cute Z50 gas tank, totally rust free

Again, not THAT much stuff I can keep, but just for the engine and some other stuff, it's a pretty good deal. If I were in Thailand, I'm sure I could find a good working 50cc Honda engine for $20, but this is Chicago!

Here is the stuff I will sell for sure. I'll have to check ebay and see what's a good price:

-Z50 Frame and swingarm

-Z50 wheels, both nice and round

-Chain guard

-Rear fender for like $1, it's cracked. 

-Seat is split open but definitely salvageable

-Right handlebar and throttle assembly

If you're on my blog and want to buy any of this, I'll set a good price for you!

So this is the starting point for the project. I basically have an engine, carb, gas tank, and a swingarm. 

First Closet Honda Design

Screen shot 2011-02-13 at 9.00.07 PM
Originally uploaded by zorgitronn

This is the hypothetical combination of parts from these bikes to make what I think is a perfect little motorcycle. 

Frame: CL 70 

Fork: CT 90

Swing arm: C 70 

Front Wheel: XL 70 16inch 

Rear Wheel: CT 90 17 inch 

Gas tank: Z50 (if it fits)

I mocked up what it might look like in Adobe Illustrator:

Introduction

Motorcycles are cool. I'm not that experienced, but I've ridden a few different types and developed a taste for bikes with the following characteristics: 

-Light and flickable (250 lbs and less, ideally less than 175 lbs)

-Low to the ground

-Small or thin wheels 

-Lots of vibrations 

-Non-obnoxious exhaust sound

-Simple, rugged engineering

-Low cost maintenance

-Fast is good but not necessary

-Knee-hug-able top tank

I currently ride a 1980 Honda C70 Passport which has nearly all of these characteristics. It's 100% stock and a blast to ride, even if the top speed is only 42 mph. Everything on it works great. 

But I need something to mess with and blow money on. Perhaps I could make this imaginary bike fit ALL of the above characteristics, and maybe look really cool too. 

Design Concept:

Small, horizontal 50cc-110cc engine Honda's seem pretty awesome. From a lot of research, it SEEMS like they have a lot of interchangeable parts between bikes in addition to the engines. This would make it easy to build up a "custom" or "frankenstein" bike by someone like me, who only has a large closet and some hand tools.

There are more than a dozen Honda motorcycles with the horizontal engines. 

Here are all that I can think of at this moment:

Z 50

C 50,70,100

CL 70,90

CT 90, 110

CT 70

ST 90

S 65, 90

SL 70, 90

SS 50

XL 70

It's a pretty diverse bunch. Lots of different frame, wheel, and suspension types. Again, they all SEEM interchangeable. This project will determine if they really are, and help others who want to build frankenstien/parts bin small Honda bikes. From hours of research, a lot of the information is very vague, so hopefully this blog can clarify some things for newbies like myself.