My 3 Pocketbike rides (Belgium)

[jorge0136]

I have always liked the idea of one of the mini bikes and your bike III might just be the inspiration I need to make one of these things. I am amazed at how clean the thing looks. Have you ever heard of a loncin engine before? One of the guys here is selling a 125cc 3 speed that I am thinking would be a decent start to a mini bike.

 

[freakboy]

i belive that engine would make you HAUL ****ING ***.

 

[iRenaat]

I have always liked the idea of one of the mini bikes and your bike III might just be the inspiration I need to make one of these things. I am amazed at how clean the thing looks. Have you ever heard of a loncin engine before? One of the guys here is selling a 125cc 3 speed that I am thinking would be a decent start to a mini bike.

That would definitely be a good and veeery powerfull start, but if I had to make a new minibike, I'd use an engine with a cilinder that stands up. A flat cilinder, like my engine and your loncin, makes your minibike a bit too long I think.

 

[jorge0136]

I think i am going to make my bike slightly bigger than the tiny size you appear to have made trike III. The length of the engine shouldn't be too big of a concern. How tall are you? You appear pretty tall in your photos, perhaps you are just more flexible than I am. I don't feel that having my knees against my chest will be very comfortable. We shall see. What was it that you didn't like about having it so long? Was it needing a beefier frame as you have a longer lever arm over the length of the frame?

Also I am planning out the bike I want to build. Where did you pick up those wheels for the last bike? The rear looks like it has a brake incorporated as well. The front looks solid, just the sort of thing for me to look out for.

 

[iRenaat]

I think i am going to make my bike slightly bigger than the tiny size you appear to have made trike III. The length of the engine shouldn't be too big of a concern. How tall are you? You appear pretty tall in your photos, perhaps you are just more flexible than I am. I don't feel that having my knees against my chest will be very comfortable. We shall see. What was it that you didn't like about having it so long? Was it needing a beefier frame as you have a longer lever arm over the length of the frame?

Also I am planning out the bike I want to build. Where did you pick up those wheels for the last bike? The rear looks like it has a brake incorporated as well. The front looks solid, just the sort of thing for me to look out for.

Hi, I'm 74inches tall (1,88meter), which is pretty tall
I would have liked to make this bike a little shorter, just because the proportions would be more realistic then...

But whatever, it doesn't really matter when it looks nice like it is now

The front is made all by myself, imitating the front of a standard motorcycle:
I've made two plates like the first drawing in the attachment, The two upper holes of the lower plate were 30mm, the two upper holes of the upper plate (the one that has the steer on it now) were 12mm. Then, I took two iron tubes that were about 40cms long, and 30mm thick (you could use suspension instead of those tubes). I slided both tubes through the 30mm holes from the lower plate, and because I welded a nut in each tube, I could fix the upper plate with 2 12mm bolts. Then, I welded the lower plate to the tubes that were through it, leaving enough distance between the two plates so I could fix the articulation with the rest of the frame between it. The front wheel is from a wheelbarrow, but it's not really good to ride over 30mph with that

Got it?

There's another drawing in the attachment...

The rear wheel works very fine with the trumble brake in it, but I can't tell you from what bike it is
If someone knows, tell me!!

 

[bigfootrules31]

i just used the front bit off a bike to save some precsious time. im going to the dump tomorrow to hopefully find : a 2 stroke mower, some wheels(small ish) anda motorbike fuel tank so i can hopefully make something a bit smaller and similar to yours my previous mini bike has been retired because of its dangeriousness.

 

[jorge0136]

I think I would like some suspension on the front. I don't know if I want to try playing with that for my first bike though. We will see. I like the idea of how the plates work together though, very well thought out. Do you have a bearing where the two plates meet with the rest of the frame? I think I have heard that part called the neck before. Do you get enough of a suspension out of your seat? It looks like it would be fairly comfortable through some bumps.

A wheel barrow wheel! Doesn't sound safe for the 45-50 mph you say it goes. I will have to keep my eye out for wheels to snag for my bike.

I sent the money off to get my engine from Rotore, so as soon as that gets back i will get cracking at the design. Was it the engine that determined the overall length? I am trying to figure out how you decided on your dimensions.

Speaking of dimensions I am 73 inches tall and I don't think I could crouch onto your bike. Could you take a picture of yourself on it? I think I would like to do a similar idea with a single tube being the backbone of the bike, rather than two smaller tubes.

 

[iRenaat]

I think I would like some suspension on the front. I don't know if I want to try playing with that for my first bike though. We will see. I like the idea of how the plates work together though, very well thought out. Do you have a bearing where the two plates meet with the rest of the frame? I think I have heard that part called the neck before. Do you get enough of a suspension out of your seat? It looks like it would be fairly comfortable through some bumps.

A wheel barrow wheel! Doesn't sound safe for the 45-50 mph you say it goes. I will have to keep my eye out for wheels to snag for my bike.

I sent the money off to get my engine from Rotore, so as soon as that gets back i will get cracking at the design. Was it the engine that determined the overall length? I am trying to figure out how you decided on your dimensions.

Speaking of dimensions I am 73 inches tall and I don't think I could crouch onto your bike. Could you take a picture of yourself on it? I think I would like to do a similar idea with a single tube being the backbone of the bike, rather than two smaller tubes.

I have two bearings in the neck, I tried to draw them with those small balls on the drawing
It's a very solid neck! The seat is a "Wrights" from before 1940, bought it for 2€, is now on my vintage bicycle:

That seat gives enough suspension for standard asphalt or concrete roads, but don't go offroad

The wheelbarrow wheel is very good wheelbarrow wheel, but it's still a wheelbarrow wheel you know
When I drive without my hands (yes, I can drive with my hands in my neck Only to say that my bike is built quite good ^^), the front wheel starts to shake at 35mph, we call it "cadans", it's when several thrill frequencies come together and get stronger. Some cars have it too, because their wheels haven't got an equal weight on each point. Try to find a wheel from a real pocketbike, or a Honda Monkey or such. Anyway, big tubes look nice on minibikes I think

The overall length: The only way to strech this bike was to make the central tube, the one where the gas tank is on, longer. With a shorter engine, I could have used a shorter central tube...
The picture attached should give you an idea how to get on my bike if you really want to race

 

[jorge0136]

I will definitely have to start looking for a similar seat. Does anyone know do they make them for motorcycles specifically? I'm thinking a small scooter wheel since I want to go just a hair bigger than you're bike. Hopefully it will have a disk brake on the wheel too. I just don't see that ball you are curled up in being very comfortable.

How thick is that central tube? I imagine it must be fairly stout. Have you thought about putting fenders on the little thing? I live in a fairly wet climate here the pacific northwest of the United states, so a fender might be nice to keep the rain out of my face.

 

[iRenaat]

I will definitely have to start looking for a similar seat. Does anyone know do they make them for motorcycles specifically? I'm thinking a small scooter wheel since I want to go just a hair bigger than you're bike. Hopefully it will have a disk brake on the wheel too. I just don't see that ball you are curled up in being very comfortable.

How thick is that central tube? I imagine it must be fairly stout. Have you thought about putting fenders on the little thing? I live in a fairly wet climate here the pacific northwest of the United states, so a fender might be nice to keep the rain out of my face.

The central is out of 3mm iron, and the overall thickness is about 4cms.
Fenders would be great, but it's hard to find them for these small wheels

 

[mike75925]

i've rode some small stuff before, but you definitely take that cake. nice builds.

 

[jorge0136]

I found this http://seattle.craigslist.org/sno/mcy/1323882405.html

A picture of a new, newstar pocket bike.

I think the wheels, throttle, brakes, kill switch etc... could be useful. For $40 is it worth the parts? I am still intending to build a bike similar to yours, I don't like the style of this one. It's possible I might just get this one working too.

 

[iRenaat]

I found this http://seattle.craigslist.org/sno/mcy/1323882405.html

A picture of a new, newstar pocket bike.

I think the wheels, throttle, brakes, kill switch etc... could be useful. For $40 is it worth the parts? I am still intending to build a bike similar to yours, I don't like the style of this one. It's possible I might just get this one working too.

Well, you couldn't miss for 40$ I think...
It might look better if you painted the wheels black.

I hate those chinese pocketbikes, they look horrible!
But I must admit that those wheels would be very good on your pocketbike

 

[jorge0136]

Well I have decided I don't want something quite that small. Although I do want something that will fit in my trunk. I don't think the the pocket bike will work if I want to make it bigger. So now I need to figure out where to get wheels. Everything else I can fabricate more or less. No news on the engine yet hope it works out for me. I wonder if I can find medium road/off road tires for some small dirt bike wheels? I will mostly want to ride this on a ride, but a tiny bit off road too. Gravel is what I have in mind. What is the diameter of your wheel+tires? 14" (35.6)