Make it stop!! Make it stop!!!

Now that the bike is running I have realised that being able to stop is also rather important. the current braking configuration that I have is not cutting it since you have to start braking miles in advance and hope that you have judged the distance correctly. If you did not, it means dragging your shoe along the tar to assist. Even running against the compression of the engine does not seem all that effective, although it does aid substantially.

So this is the current braking setup:

Both of these brakes are individually activated. The top one is activated by the driver and the bottom one is handled by the passenger. the First step is going to be linking these two brakes and making them work off the one cable. with both of those working together the braking is already SUBSTANTIALLY better! For the top brake i found that the origional cable was very stretchy over that distance, the friendly guys in another department at work gave me a piece of 3mm stainless steel cable. It fitted into the standard cable guide (pushing it through was a little bit of a mission though) and has made a world of difference to the way the brakes work.

On the other end I'm building my own V-brakes. The V-brakes just make sense to me in the form of stopping power due to the larger amount of leverage on the brake pads. There are many discussions on the pros and cons of the various different rim braking mechanisms and I think one needs to get to a place where you make up you own mind and go with what you prefer. I prefer the V's, and the seemed the easiest to fabricate... This is where i am right now.

I have made myself some posts that i have welded to the for. As i have said before, every bad welder needs a good angle grinder... These welds have yet to be cleaned up and the pins straightened - i struggle to get the welds not to make everthing pull out of kelter.

Then i have started with the actual moving parts. I took a piece of 5x40mm flat bar and cut it diagonally. These will be the arms for the brakes. I might need to add a little tab on the outside to get the arms closer to the wheel since the fork is as wide as it is.

On the V-brakes there is a little piece of tubing that is bent at 90 degrees  and acts as part of the cable guide. This little part had me stumped for a couple of days. Being a technician in a hospital I started scratching around and i found this:

The metal ends in a broken stethoscope are the perfect size, already bent and is stainless steel. SCORE!

I have made a couple of little mods for variaous reasons and need to post those here as well.

My wife complained about fumes while we were riding and I then lengthened the exhaust in a successfull attempt to move the fumes a little bit back. I used some standard 15mm copper pipe and 2 45 degree elbows that were soldered in place, Wrapped a little piece of old rubber tube around the end tip of the exhaust and slipped the elbow (that is now sport 2 slits) over that. Fastened it all up with a hose clamp and secured the end with a little piece of wire. I hate using wire but it was all I had.

i thinks it looks pretty cool and the rubber makes a surprisingly good seal.

The airfilter seemed a little restricting so I added some holes to let more air in. That also made a bit of a difference in the performance of the motor since it is now not being starved for air anymore. now the aircleaner now looks like an alien - not planned.

Further plans before painting include panniers underneath and behind the babyseat for some added packing space.

But first we need to make all of this stop. :)

RIde on!

It has been a while and MUCH water has flowed under the bridge with this bike. Tried and attempeted all kinds of things and had so much fun that I forgot to update what has been going on.
The fork has been a massive deal to me and apart from some finishing it is done and working like i wanted it to! really stoked. now we just need to add some brakes, a bicycle with no front brakes might just as well not have brakes at all. This is a mtter of great concern for my wife who is the regular passenger on the bike. I have decided to try and find some old cantilever or V-brakes since they will work the best considering the availability of mounting spots. I also expect that these will not mess too much with the look of the fork.
I seem to have had some issues with judging the tension of springs completely, underestimated every spring i bought. The ones for the fork could hardly carry the weight of the fork, even though these were the toughest ones on the shelf at the hardware shop. I found a little company In Durban called "Spring Manufature and Design", they are situated out in Jacobs at 277 Balfour Road and I can really recommend these guys. They can make anything you need from the heaviest duty coil or blade springs to light little springs. I was able dig in in their over run box and found what I needed. I ended up using 3 stacked stainless steel coil springs. This is perfect, provides a little suspention and does not bottom out under my weight on the bike. i used the wheel mounts from the donor fork. They worked perfectly, and matched the look of the the fork well!
I mounted the chain tensioner. I swopped the skate board wheel for the tesioner wheel i got in the kit because it gives a little more guidance to the chain. the skateboard wheel was not worn flat and made the chain derail. after fitting all of this and making it look fair i tried making the engin turn by engaging the clutch and pushing the bike. even with a MUCH beafier spring the engine pulled the tentioner down so much that it jammed in the frame. so i hade to revert back to the one that came with the kit. Working on another idea to try and make the home made one work.
there are unfortunately no detail pics at this point. but i have been riding it to work and have been enjoying the bike too much! I found that it needed a bit more air so i drilled extra holes in the air cleaner cover . I'm currently trying aout a bit of a longer exhaust. My passengers were complaining about being fumigated. The longer exhaust seems to have added a bit of back pressure, and has resulted in a bit more power.

here are some pics at work and on a recent trip to the botanic gardens:

the baby seat was a hand me down of a hand me down and i could not get it clean. so i got some enamel paint and painted it. I first sanded down the brittle coating that the sun  had created  and the i put on the paint. Worked well, the seat now looks like a bought one...

i'm trying to figure out some sort of a pannier for below the baby seat. Just some extra packing space. after that, paint. keep you posted! 

Just had to

With things lowing down at work and having massive amounts of freedom and a big bin of old scrap metal, i got to jump into making something that i have been toying with in my mind for many moons. This tandem is very obviously a great candidate for a custom front suspension. Yes I did, or am busy with it at least.

So i went off to a local bicycle shop and got hold of a little BMX fork for R55 (it about $6 US), all I really needed was the stem. I did not want to cut the original fork, just in case. Here is the comparison:

I cut and welded and made excessive use of the grinder. Every bad welded needs a good angle grinder... The down pipes looked really nice when i first pushed everything together:

Lots more cutting welding and grinding was done and it eventually got me this far:

Bad nighttime photographs with too much flash - sorry. everything is pretty much held in the air with over-tightened bolts and a piece of wire, with the bike suspended from the rafters with a tie-down. big balancing act that you wont see in the circus. i have got some springs that will be going in the gap. now that i have actually got it in the frame i could get some much needed measurements to carry on with the fabrication. 

The chain in the kit needed to to be MUCH longer for the tandem so i decided to just buy a whole chain instead of joining and linking things together. I managed to find a place in Durban that had the correct size chain, and the chain is currently in had. it does look like I'm going to need to use the bulky chain tensioner from the kit as well just to solve some clearance issues. but more on that when there is something to say.

now you see it now you don't...

Thought I'd just ad a quick before and after of the rust removal. This caliper was particularly bad.

I sprayed it with the oil and left it a couple of minutes. took the steel brush to it and there you have it.

This one was fairly badly pitted and did not come out as nicely as the cranks but the difference is still worth the little amount of effort that it took.

Better than a bought one

The whole crank hitting the engine issue has been hanging over my head. mainly because i have been forgetting to take to work so i could heat it up and bend it. I remembered yesterday and got it done.

Anybody want to give a little acetylene port-a-pack for Christmas or just as a gift, I'm an open receiver and would be glad to oblige. Would love one of those at home. Anyway, clamped the crank in the vice, heated it up to a nice orange, and bent a slight "s" into the arm. Got home after work and tried it. First time lucky. I managed to bend it the perfect amount to just clear the engine nicely.

In the meantime i noticed that the chrome on this crank was looking rather bad. If you looked carefully at the "before" picture in the first post on this blog, you would see the left front crank has lots of surface rust. I had heard about a remedy for this and was keen to give it a try. It involved spraying the surface rust on the chrome with a penetrating multi-purpose oil. Letting it all stand for a while. Then attacking it with an abrasive. The guy that told me about this (thanks Shaun) suggested using a finishing brush (steel brush with brass bristles) or a scotchbrite pad to not damage the chrome finish. I had neither and was not particularly fussed about how much the chrome shined after the rust was gone, it just had to disappear! So i used the workshop steel brush.

Well it worked surprising well. Rust is gone, everywhere that i could get in with the brush and the chrome was hardly touched. Nice, easy, effective. I like it. All the other cranks got the same treatment today.

The tank that i got with the kit is not the most attractive fuel tank i have ever seen, but i have nothing else so it will have to do.

 What really got me was the factory paintwork on the tank. It was terribly runny, and coarse. Bearing in mind that i was going to have to repaint the bicycle frame, I feared that people might thing that the paint work on the tank was my own and that had to be changed.

It also gave me a good reason to get another color on the tank. You know make it match a bit better...

A little piece of 100 grid sand paper quickly did the trick. the Chinese are know for cheap manufaturing but not always for quality. We just say that after having put the sand paper to the tank, I'm glad that i repainted it. That paint came off really quickly. I made the tank two tone leaving the underneath black and painting the top white. I used the Duplicolor engine enamel because not only is it heat resistant it is also feul resistant. So the color on the tank will not run when you have filling accident. I like it.

Looks better than a bought one now. :)

The tension mounts

So with the length of the chain that i will be using I expect some stretch. The engine kit came with a chain tensioner but its an ugly bulky one. It also has the possibility to twist into the back wheel when mounted effecting in a sudden unannounce stop. I did not like it, so I decided to make another one. I wanted something that could handle a fair amount of up and down and a little bit of side to side tension as well. I also did not want to do a whole lot of cutting and grinding, fabricating something from scratch. so i started looking around to see what is available that would only require slight modification.

When they bought a bunch of new equipment at work some of it came with a little open ended wrench, for installation, that had 10mm and 8mm heads. There are hundreds of these little wrenches lying around at work. Yesterday one of those went missing...

This wrench had the perfect length for the area where the tensioner will be fitted. I welded the two open ends shut and filed and ground them flat. Drilled holes and mounted an old skateboard wheel to the one end.

 The other end will be fastened to a tab that will be welded to the frame. I made this tab using a little piece of tubing an a piece of flat bar. I welded these together, attached two nuts to the top of the resulting circle that can take a pinch bolt. An old skateboard bearing goes into this little clip to act as a swivel for the tensioner.

I can however only mount the whole assembly once I have the chain in place so that i can find a good spot for it. I might have to add another tensioner somewhere closer to the engine but we will have to see later.

This tensioner will auto tension with a spring creating a little less maintenance than the one from the kit that requires manual adjustment.

The next step to getting the chain mounted is fitting the sprocket to the back wheel. It also is an ugly sprocket and needed a little bit of, well sanctification.

So I made it holey so to speak. Looks a lot better...

and here it is painted. i'm enjoying all of this far too much...

let the game begin

Ok so the tandems reform kicked off this weekend. Even though the engine arrived two weeks ago life has just not permitted the commencement of the fun…

So this is what I started with. A standard 12 speed tandem bicycle with a little baby seat at the back to make it fun for the whole family.

Originally the engine would go in the back behind the front seat, this however posed a bunch of building issues that would make the project take a little longer. Problems involved new engine mounting spots that would have to be fabricated, the frame would be in the way of the exhaust and if you change the routing of the exhaust on a low budget, you could be facing leg burn problems for the rider at the back. Longer throttle and clutch cables, longer fuel lines etc. etc. etc.

After sitting with the bike for a little bit my wife said: “just put it in front”. I (for some strange reason) never really considered that option. The exhaust would work, I could use all the standard cables, hoses and mountings. All I needed was a longer chain. In fact it will be a bit of a monster chain but that is ok… we can deal with that!

So minor changes where required for the bike: I literally only needed to remove a piece of the extra crossbar in the front.

I decided to leave the little piece in the front for 2 reasons: 1. it kind of leaves the original lines of the bike in tact and 2. the angle grinder did not fit in to cut it off flush with the neck and I had nothing else to cut with…

I took the piece that I cut out, fished the ends and welded it back in, parallel with the seat post tube. Nice welding practice on thin walled tubing. I nearly tore my hair out a couple of times, but that is how we learn…

So now the engine sits very nicely in the frame with but one snag. The pedal crank on the left does not clear the engine and needs to be bent ever so slightly to make it work.

I planning on just making it black and white, want to try and keep things simple.

More next time.