Folding bike and/or H Frames

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Mukura

New Member
Nov 30, 2010
17
0
0
Hamilton, New Zealand
Anybody else had this idea? I really want to try it, and have all the parts to do it, my question is, as long as the carb is level most of the time are there any issues with motor bearings?

Cheers - Mu

 

NEAT TIMES

New Member
May 28, 2008
1,964
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PENSACOLA, FL
Mukura

two cycle engines can run in any position, even upside down as the oil is in the gas and transfers thru the crank case and lubes the bearings etc.

The china girl type carb needs to be in a level position as it has a fuel float and fuel needle valve.

If set up with a diaphram carb like on chain saws and a lot of mini bikes, scooters and mini choppers they can run in most positions.

I have a fold up stainless steel bike like that with a friction drive, called "island hopper".

My thought; a rear friction drive would be much better and dependable. The engines like in the picture can be very troublesome, but you will learn a lot! Lol

good luck, keep us posted if you can! And welcome to the forum.

I would post a pic of mine but they have been posted, can`t post the same pic twice.

Ron
 

NEAT TIMES

New Member
May 28, 2008
1,964
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PENSACOLA, FL
Mukura


I did not read close enough. You have the parts, go for it.

With a diaphram type carb you should be able to make or buy a fiber like spacer/adapter to bolt it to the cylinder. The fiber/ plastic like adapter acts like an insulator to keep the carb cooler.

You can use a hose of proper type for modifing the intake to level your float type carb.

Ron
 
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Mukura

New Member
Nov 30, 2010
17
0
0
Hamilton, New Zealand
Oh, sorry if I mislead you. This is not my creation. It is from A folding bike built in Launceston using ZBox Super 66-3 engine - John from Launceston 2010, you will see it at the bottom of the page. I stumbled upon it when I did a google image search for motorising a mixte (which you can see on page two of the above gallery).

It's funny as last year, after I finished my first build, I aquired this bike - a NZ Made Healing Cruiser, very similar to a Raleigh 20 :


When I got it I thought about motorising it, but couldn't see how to fit a V-Frame centre mount motor and maintain a low centre of gravity. What I did really like was that the rear carrier rack is welded on, and could easily be converted to accomodate tank and a hinged seat, similar to a factory moped, adding security for the fuel, and a mor relaxed riding position. Anyhow, I restored it as a singlespeed bicycle and sold it the other month.

My girlfriend has a bike like this :


which she's restored, in the process, she picked up a parts bike, actually, the one pictured, which she put all the b-grade gear on and sold a couple of months ago. I talked to her about a frame swap, as I figured the lo-line was ideal for the v-frame mount, she was open to it, but as I was a bit cash strapped that week, and have quite a few other frames to choose from I went for the quick buck as the 70's NZ Made bikes are reasonably in vouge with the early 20's hipsters lately.

I do have a 16" version of the lo-line stored away, but the rear triangle has seen better days, I'm looking for a way to bring that back up to scratch, but in the mean time I picked up a bike at the tip for $15, with a bunch of parts I wanted. I set the frame up on some old spare wheels and listed it for sale, but there was little interest, so I used the handle bars on another bike which I knew would sell like hotcakes, so I'm back to being stuck with this frame :


made by Lespo, who incidentaly do mini velo, and some pretty cool fold up bikes. Originally I thought about a chop and fitting the 16" loline front end onto this.... to keep this entry brief - I stumbled onto the z-box site, and the picture in the original post, and as I have three motors in storage, I thought I'd work on a fun project this winter (southern hemisphere) and aim to hit the holiday market with it come october to offset the cost on my other serious projects....

So, finally to answer your question fm2200, how much does it wiegh? I've got no idea.

Neat times - thanks for your reply, advice and wisdom, it's much appreciated, and funnily enough, more or less the answer I was hoping for. With my original build, in album on my profile, I was riding to work last summer daily, I've clocked around 1500miles and have learnt a few of the basics now... more the point of this story is that one of my old firms clients was a pilot, and he was enquiring as to whether a folder could be built to fit in a single or two seater aircraft, as once he reached his destination he would then have to travel by foot everywhere. When he asked me I did recall my father telling me about the bikes the paratroopers had back in the day, and I did tell the pilot bloke that one way or another I was sure it was achievable. Good to hear you have a reliable solution to this challenge. Out here there seems to be a lack of availability of this kind of thing, as the market base is sooo small. We're looking at national population of about 4Million, where as two thousand kms to the west that's just a normal sized city... I'll bear the rear mount in mind, and if I see a fold up going for the right price I'll then be on the hunt for an old weedeater or similar, then briskly off to the landing strip at one of those 'gated community' type beach towns dance1

So... back on track with the thread topic. Sound's like all I need to do is modify my inlet with a bit of brazing. Cool, now I feel I have some creative direction for the next few months. I'll try to remember to add some build pics up as I go, I'm normally very slack about documenting the process, but will make an effort to share the details. Thanks a bunch for your feedback guys.

M
 
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wheelbender6

Well-Known Member
Sep 4, 2008
4,059
221
63
TX
Cool. There is a motorized folder on RatRodBikes where the builder added ape hangers and a banana seat.
 

rohmell

Active Member
Jun 2, 2010
1,531
6
38
New York
...
I would post a pic of mine but they have been posted, can`t post the same pic twice.

Ron
Take your picture, rename it, and resize it, or crop it slightly, and it will become a 'new' picture that can be uploaded.

OR
Use one of those picture hosting services such as ImageShack. Put the image there, and you can link from it all you want.
 

Mukura

New Member
Nov 30, 2010
17
0
0
Hamilton, New Zealand
Update :

I had a chance to pull out some frames from the roof space today and have a look at a few ideas.

I've got a Raleigh 20 Frame arriving in the post soon.

Also, the Raleigh chopper Mk III, may be a candidate as it has the all important 45 degree angle bracing bar.

another idea for bottom mount horizontal is sliding a down tube of donor bike, through hole drilled in bottom of bb housing on desired frame - pushing through into the bottom end of the seat tube - weld/bolt together... oriented so that seat tube of donor bike is left pointing toward forks of desired frame - then from seat tube collar clamp run bracing up to top tube of desired frame... thin tubed 80's bmx as donor should sleeve well.
 

Mukura

New Member
Nov 30, 2010
17
0
0
Hamilton, New Zealand
Update :

Well, it's been a heck of awinter here for me, car trouble like you wouldn't belive is just the tip of the iceberg.... ANYHOW!!!

The good news is I've picked up a Raleigh 20 frame, which I just happen to have a set of forks to fit, formerly off a 24" MTB with disc brake, so I'm looking through my collection to relace onto smaller rims and generally standing back and doing a fair bit of chin scratching and making sounds like mmmm, and ahh, or is that err?

One thing I did chek out as soon as I got my frame was motor alignment. It turns out that if you roatate the engine in any given direction the outcome is much the same as far as work involved and get this - the engine does not shrink - that's right it still takes up the same amount of room! Now, I know some of you brighter members will have already known this, and there are probably some genuises who have already figured the next part of the equation too... Here goes, with marginally less work one could bottom mount the same motor in a horizontal fashion by drilling through the bottom bracket of the H-Frame bike, and inserting a chopped front triangle from a donor - that is insert the seat tube of the donor up through the bottom of the H-Frame seat tube, leaving us with a lowered bottom bracket, and a spar mount from the donors down tube, which may or may not be braced back up to the top tube of the H-Frame. Also the donor could have the chainstays left on and braced back to the dropouts on the H-Frame, the end result is a very low motor, and a very low centre of gravity, much like a motorcycle.

Ok, so it goes off topic a little from the thread title by orientation verticle, but that's something I'm willing to risk in this journey of discovery - because a lot of the original thinking in the horizontal mount was to lower the whole deal without customising the droupouts and worrying about how good the welding job is etc. One could accomplish this with very few tools and hightensile bolts to join the two frame sections.

The next logical step to me is to trim down the hieght of the H-Fram seat tube so that :

A) The donor V pokes out the top and can be given a new collar, with a set pin to help the joining, that is to say gravity would hold it up there : ) and..

B) The seat stays on the H-Frame could be lowered also, which in turn would allow for a lower seat, which would once again make for a lower wieghted ride... and if you look at some of the older cycles, or any given motorcycle (shocks) these stays are bolted

Now of course anything like this requires a great amount of care and attention to saftey aspects, but the key thing is your average person could fab this up and take it to an engineer ready to go for welding, and the cost would be low as all the prep work is done, resulting in an hour labour plus materials charge out rather than four or five hours worth of work getting them to build your custom frameset.

It's some food for thought for sure... mind you, it works the other way around too... but woud require a little more work... insert the donor seat tube upside down and use the donor top tube as the spar - for - you guessed it - a horizontal mount, then using a sleeve/shim sort of system, reset your bottom bracket from the donor (with chainstays?) and continue as per above.... which brings us back to the correct orientaion for this thread... not as low, and a little extra work, but you have to admit, it would look awesome - and - if anybody asks why the reply can always be - because I could. The next step from here would be to maybe apply this to a 16" to fit in the back of a car nicely... or then there's another idea, which I've seen some come close to, but not quite pull off the simple clean way - but that's another thread..

Oh, and as for the Raleigh 20 Frame I have, the upshot is do the minimal amount of work to it and sell it un-motorised as it's worth more in the current market here that way - I will at some stage do a photo-chop session to explain the ideas in here in pictorial form because it's all about making life easier for other readers, well that's the world wide web I dream of anyway - with very good keywording, so it comes up in search engines... but again I digress and ramble, or meander...

Still, I'd like others to contribute to this thread if they see a way for improving - finding simpler ways to achieve much better looking rides. I'll update again soon, and then probably move on to the thread for the other ride I'm ACTUALLY building at the moment

Cheers