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Kobber
02-17-2010, 10:48 AM
Hi everyone,

I was reading through the plans for the LodeRunner2 tandem trike the other day and paused at the description of the stoker drive chain crossover setup. For those of you not familiar with the plans, and without going into too much detail, the stoker's chainring is mounted on the right-hand side of the pedals (standard), but the chain is driving the left rear wheel (the captain drives the right rear wheel), making it necessary to transfer the drive across the frame of the bike with a double freehub setup that is really quite ingenious.

My question: has anyone ever seen or attempted to custom build a bottom bracket with the chainring on the left? It's too cold for garage tinkering around here right now, so I'm tinkering in my head. Anyone got any food for thought?

Thanks and take it easy.

kobber

Kobber
02-17-2010, 10:59 AM
Five minutes later ...
Just found this picture in the gallery:
http://www.atomiczombie.com/gallery/deltatrikes1.html

Just one more reason to love this site.

The front pedals are mounted with the chainring on the left. Anyone have any ideas who built this wonder and what the deal is with the front BB?

Thanks and take is easy.

kobber

Kobber
02-17-2010, 12:00 PM
Sorry, just realised the link ain't working the way I wanted. What I'm looking at is the Tritan Hauler by Eric Bevans (bright orange with fuzzy white seats) on the Delta trikes page (http://www.atomiczombie.com/gallery/deltatrikes1.html)

Kobber

Radical Brad
02-17-2010, 01:25 PM
That trike is using the classic tandem crossover system. The front ring runs to the read ring (which has two rings), and then from the right rear ring back to the freehub as normal.

Brad

Kobber
02-17-2010, 05:12 PM
Hi Brad,

Thanks for getting back.

Now, it looks to me like the front rider's crankset on the Tritan Hauler are set up with the chainring on the left. Am I seeing crosseyed? That's doesn't seem to surprise anyone, but I've never seen a bike like that - and I assume there's a reason for it. I can't really tell where the chain's going from there, but that's not my problem right now.

What I would like to know is whether anyone has tried to set up a chain entirely on the left side of the bike - from the pedals to the rear axle - without a drive chain transfer device like the one you devised for the LodeRunner2 somewhere in between.

I reckon you could just mount an axle left-to-right and put the chainring on the left-hand side, but then the threads to mount the pedals would be wrong and they'd come loose. Does that make sense? Can you think of anything else that would get in the way?

I suppose a custom axle would be necessary, with non-standard (opposite) threads to mount the pedals. Any thoughts?

Take it easy,

kobber

Radical Brad
02-17-2010, 06:13 PM
What you are seeing is the exact same thing as this...

http://www.lucidscience.com/temp/tradewinds2.jpg

This is the classic linked tandem drive system, where the stokers crankset simply has two chainrings.

You can only have a left side drive if you use a Haro LSD (left side drive) rear hub and freewheel. These are very rare (1 only have one), and do not come in clusters, just the single speed 14 tooth freewheel.

There may be other ways, but besides machining your own LSD pawl system from scratch, i can't think of a way.

Brad

PeterT
02-18-2010, 08:10 AM
I have played with a complete LHS derailleur,(custom built!) and with putting a sprocket on the LHS to see if I could drive a wheel fitted with the sprockets on the LHS, ie driven wheel at front, chain drive sprocket behind wheel, with Der hanging on the LHS, and I got it to work, but lots of headaches in doing it!

All the best!

PeterT

Kobber
02-18-2010, 09:03 AM
Thanks for bearing with me, Brad, 'cause I'm not sure I'm making myself clear. That LSD went right over my head.

Take the Tradewinds, it's a perfect example. The captain's pedals - right up front - look like they're mounted left-to-right: the chainring is on the left. A standard crankset would have the chainring on the right.
Right?
Can you simply mount the chainring on either side of the crankset axle? I thought one side was slightly longer to allow for this.
:confused:

Thanks again and have a great day.

kobber

Racer46
02-18-2010, 10:16 AM
If you're using a BB with seprate axle & bearings you can turn the axle around so the long side is on the left. If you're using a sealed BB then you will have to turn the housing around. Use a thread lock compound to keep the pedals and bottom bracket from un-screwing.
The biggest obstical that I see is that if you mount the wheel with the cassette on the left it will only freewheel when you pedal. I don't know enough about freewheels & cassetts, maybe someone who is smarter than me will chime in with a way to run the casette on the left side. Of course if you're making a "Fixie" then there is no problem.

Radical Brad
02-18-2010, 02:48 PM
Yes, you can mount the chainring on any side you like. On the TradeWinds, You do not have to worry about any BB hardware unthreading because the axle is still spinning in the same direction. If you want to keep the slightly longer side on the left, just reverse it.

The pedal threads are now bakwards (reverse threads are now on the right side), but I have never seen that become a problem, and I am the type of rider that likes to launch in high gear and crank hard.

Your real challenge is what are you going to do with your rear wheel. There has never been a left side multi-speed freehub produced.

If you're thinking, "well, I will just flip the wheel around"....

The freehub will no longer work because it has to spin in reverse, and you will never find a left side rear derailleur!

So unless intricate C&C is your game, you will never be able to have a left side drive rear wheel (with the exception of the rare HARO LSD).

http://www.lucidscience.com/temp/pawls.jpg

Brad

Radical Brad
02-19-2010, 07:03 PM
I made up a little info set on freewheels, just to show how they work internally...

http://www.atomiczombie.com/ct-freewheel.html

This should explain why they will never work if installed in reverse.

Brad

Kobber
02-22-2010, 04:10 PM
Hi Brad,

This is slowly sinking in. Thanks for your perseverence.

What I'm planning is a combination of things I've seen you do and other bikes available commercially. I'm hush hush on the details for the moment mostly because I have very little worked out so far, but the two axles will look like what you did on the Kyoto (got those plans too): the left rear axle has the freewheel mounted just like on the right side, ie to the right of the inside pillow block bearing. No flipping stuff around - at least not without getting someone's experienced opinion on it.

Thanks for sharing your experience on the crankset. The weather will be warming up very soon around here, and I had better get planning. I have a feeling this first build is going to be a mind-opening experience.

Take it easy.

kobber

Radical Brad
02-22-2010, 08:57 PM
You should have no problems with that design. One thing to keep in mind is that there are no left side front derailleurs out there, so it will only be single speed at the front.

Brad

PeterT
02-23-2010, 04:06 AM
You should have no problems with that design. One thing to keep in mind is that there are no left side front derailleurs out there, so it will only be single speed at the front.

Brad

at least not commercially available LHS front ders, but you can always be the first to make one!

Kobber
02-23-2010, 04:29 AM
Oh, I'll have plenty of problems, Brad, I'm absolutely sure of that. Many and diverse. Like the fact that I can't find anyone who will sell me steel - at reasonable prices - in lengths of less than 6 metres. Yikes, I may have a bit left over, eh? But that's not going to stop me. I think I may even have the energy to get started on my winter garage disaster area tonight after work ...

Thanks for the idea, Pete, but that might be for a second build. What I'm planning seems to be innovative enough for the time being.

kobber

savarin
02-25-2010, 09:12 AM
at least not commercially available LHS front ders, but you can always be the first to make one!

Sorry, but I did it ages ago:jester:
Actually it wasnt very difficult to do and works flawlessly.
I suppose the pics are in the old forum.

Odd Man Out
02-25-2010, 09:47 AM
Sorry, but I did it ages ago:jester:
Actually it wasnt very difficult to do and works flawlessly.
I suppose the pics are in the old forum.

You could always repost them for the furtherance of enlightenment.

Kobber
03-08-2010, 11:27 AM
"What has been will be again, what has been done will be done again; there is nothing new under the sun."
(Ecclesiastes 1:9-14 NIV)

Just flaunting my prodigous use of Google. And hoping that I will have something a just a little bit different to show for my efforts come summer time ... even if it ain't a LHS front derailleur!

kobber

Ticktock
07-21-2012, 12:05 PM
Hi Kober,
This is not quite right! On Loderunner2,
both chain rings are on the right, and both drive a normal rear cassette/derailer unit.
The Stokers chain drives direct to the Right rear axle. same as in Loderunner 1
The Captains drives into the X-over, to allow the BMX chain to drive the Left axle.
In this case, both can change gear and peddle or stop peddling without affecting the other.
The perfect system for a tandom trike .
In the case of the KYoto cruiser, it simply uses two completly normal drive trains, with no need for any x-overs or left side cranks. Again, totally independant drives.
Viking uses a different system, and it is not totally independant drives or gear change. Here, left side cranks are used.
Trade winds is a fully coupled system which keeps the two in phase with each other, and in the same gear, provided that the same size chain rings are used front and rear on the left.
Hope that helps
If needed the x-over system can become another "gearbox" to extend the range of gears on a long bike or trike, and with 20 inch wheels this may well be needed.

Have fun,
Steve G,
Beijing

TheKid
07-21-2012, 06:12 PM
Right. One way it will work, is to make the rear axle longer, and install the freewheel adapter to the left of the stoker main beam, with the threads facing right. Some mods to the rear end would probably have to be made to do this and make it look good.

darnthedog
07-21-2012, 09:29 PM
Hey Ticktock-Steve G
I noticed a lot of old post being revived with answers by you last couple days- Top left corner is a date- for example the post you are replying to is from 03-08-2010. Wasn't sure you noticed that. It is not an issue to give the advice- but the member may or may not be active any longer to receive that advice or to answer your questions. However thanks for your creative thinking. Would have sent a PM but you do not have that active on your account.

Ticktock
07-22-2012, 10:48 AM
Thanks for the advice! New to all this stuff .
I cannot find out how to turn on messages anywhere, which means I probably did not look in the right place!
Still learning how this forum stuff works, and it is a lot more tricky than welding two bits of metal. I can see the metal!
Any help on how this forum works is much appreciated.
Steve G
steveg@myself.com

Kobber
07-22-2012, 04:01 PM
Hi Ticktock,


Hi Kober,
This is not quite right!

You're right, and it took 2 years for anyone to notice! All that cross-over talk got my chains mixed up. At least I asked a question that people found interesting ... even two years down the road.

Still haven't managed to build my first custom, recumbent ride, but I'm still lurking in the forums and still dreaming. Right now I'm building a Hase Pino knockoff ... in my mind, where the welds are always perfect.

Take it easy.

Kobber

Kobber
07-22-2012, 04:09 PM
Hey Kid,

Still hanging around. Haven't got that all-important first build out of the way yet, but still lurking and dreaming. Will find the time one day. Of course, having another baby was probably not the best way to advance my plans! For my grandchildren, maybe ...

Take it easy.

Kobber

Ticktock
07-23-2012, 07:34 AM
Hi Kobber,
Guess I noticed because I spent an eternity trying different layouts before I built my trike.
I did consider two peddlers , but finished up with just me doing the work while the boss sits in luxury,
and answers all the Chinese questions that I cannot answer. Very useful to carry your own personal interpreter with you when you ride a strange bike in a foreign land!
Thanks for the tip on perfect welds--I always knew there was a secret place that it happened-and certainly not in my workshop.
I guess I dreamed and schemed for a year before I found this group, and got the nudge I needed to get started.
I built a horse draw carriage a few years back , and on the first outing, I was stopped for the usual passer by inspections, and one said " Very good, you can certainly use a welder!"
I replied " I can't use a welder, but I really can use a grinder!"
I think most of us would have had that problem except Brad, whose welds are perfect ---maybe he is dreaming all day????
Have fun,
Steve G

wonderer
12-09-2012, 05:38 PM
If you're thinking, "well, I will just flip the wheel around"....

The freehub will no longer work because it has to spin in reverse, and you will never find a left side rear derailleur!

So unless intricate C&C is your game, you will never be able to have a left side drive rear wheel (with the exception of the rare HARO LSD).

http://www.lucidscience.com/temp/pawls.jpg

Brad

Brad,

A question, with the splined gearing clusters I've seen advertized.........could'nt you reverse the rear wheel putting the spline on the left side & put the gearing cluser on backwards (small twards the spokes, large side to the outside) It would rotate in the right direction, on the left side.

Never owned a splined back hub & don't know what holds them on.

wonderer

Radical Brad
12-09-2012, 07:17 PM
It doesn't matter how you mount the chain rings, you will still end up with the ratchet working in reverse on the left side of a wheel. To see this, do the following...

1) Take your socket wrench and set it so that it ratchets (clicks) as you spin it in the counter clockwise rotation as you hold it so the socket is to the right side of the handle. This represents a standard bicycle wheel with a freehub.

2) Now flip the wrench over so the socket is on the left side of the handle. As you will see, it can no longer drive in the correct direction, only ratchet. This is why you would need to purchase a HARO LSD (left side drive) wheel and freehub. But you won't find a multi speed LSD freehub as far as I know.

I almost never say that something can't be done, but making a fully working left side bicycle transmission with front and rear shifting.... yeah.... can't be done!

Brad

Ticktock
12-09-2012, 09:45 PM
Brad is correct! And he gives a good way to prove it.
Which ever way you try to use "normal" parts on the LHS, it won't work .
If you simply flip a normal screw on hub, you will not be able to retain a screw on free wheel, single or multi speed--it will screw off under drive.
There is no way to fit a multi speed screw on free wheel on the wrong way round--there are no threads at that end.
It may be possible to fit the sprockets onto a splined hub in reverse order, but the free wheel will still be wrong, as in Brads example.
Even if you get this thing to fit, there is no LHS rear derailer available, and a normal RHS one would be trying to work from in between the spokes!
Better than having to keep saying it can't be done, perhaps you could tell us why you think you need to do this in the first place.
Just about everything you could ever need has been done using normal bike parts, so there is almost certainly a known answer out there somewhere.
Steve G.
Beijing