Ok sap is rising and it's time to start a new build ??? Noooo....

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Hi all

Ok sap is rising and it's time to start a new build ???

Well no , being realistic I have 2 incomplete builds AND no where to store a new one.

So the answer is ?

Finish the other two , get rid if I don't like/want/need them , then I will have the space ?

So No 1



FWD and iLean rear end , so why unfinished ? From here Steve Nurse ' Fred bikes '

Problem 1:- Well I started building a 2 wheeler , goofed and when I thought a iLean would be smart and so added the tilting wheels without realising the boom needed to be longer , the row of holes on the lower beam are where the seat should be I had to add the upper beam to get the wheels to clear the seat when they rise.
Problem 2:- Each year I would drag it out and try and find an easy way to add brakes to the front fork , the chain/pedals/rings were always in the way of the brake hardware or cables or both.
Problem 3 :- I hate tiller steering and this has loads of it

Problem 1 solved a while ago and wooden seat ditched upper boom added and a moulded Flevo seat fitted - crude but works
Problem 2 decided to reverse the cable entry on some V brakes and put them in front on the fork
Weld a suspension fork bridge to the back of the forks for a second V brake



This is the bridge welded to the back being masked for a quick waft of paint as the weather is good ...



I was shaping the bridge yesterday so I could match the stud position when last night I came across a picture of the bike that inspired me [ Steve Nurse ' Fred bike ' ] when I noticed the studs were not in line ???

Turns out the fork rake puts more of the wheel in front of the fork than behind so the rear studs need to be lower , mistake averted by the skin of my teeth ...



I made a small bridging plate between the crown holes and fastened 2 brake arms with shoes and clamped them tight to a sacrificial rim and welded the bejeebers out of it.

Problem 3 may be address by USS if I find I like/want to keep it.

Unfinished No 2



This was an attempt to improve on my Ez-1 Super Cruiser bike [ in the back ground below ]



So I was after 20 x 20 not 16 x 20 and higher pedals , anyway I bought a Oke-Ja which is very good for short trips/shopping etc so this build got side lined ...

Question is what to do with it ?

The Oke-ja only has 7 gears however it does have roller brakes and so is a nice winter bike as they have needed no maintenance in the last 2 years.

Or could I turn it into a rowing bike ? I really want one to give me more of a upper body work out while riding ?

Somethink like this :-




However how to achieve it is a bit of a puzzle currently.

Any ideas you inventive lot ?
 
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The use of a sprag clutch and a rewind spring would probably do it. Sprag clutches are relatively cheap, but where to source a decent rewind spring? I would suggest steel cable rather than chain maybe?
There are several cable or chain operated rowing bikes out there (even tandems) I wonder if they sell spares? A spring (or 2) from an old-fashioned set of chest-expanders for the rewind?
Sounds an interesting project for sure. It will be interesting to see how steering is maintained while rowing.
 
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This will go some way to explain it.


There's no need for the jackshaft, the builder could have gone straight to the rear sprocket. The chain is effectively moved back and forth over a std freewheel socket with the forward stroke equivalent to back pedalling and the rearwards pull normal peddalling. Half of the effort is completely wasted in resetting and the rearwards stroke has to catch up to the road speed before it adds any effort to the rear wheel.
 
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Ok a bit of back ground needed me thinks ?

I don't want it for going fast nor long distances so wasted effort is not a concern.

What I want is a full body work out , and if I could get that whilst doing one of my normal rides that's a bonus , hopefully it will only be a bit slower than the Python trike ?

So this one more matches the existing shape I have to play with , so less hacking needed , also it drives as you describe :-




However it has cable steering , now may prove a challenge.

Also I realise I will have to use a hub gear as I doubt the forward pull on the chain will be enough to change the rear sprocket ?
This of course is safer in that it can be changed whilst stationary ?
 
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I'd think that you'd want the gearing very low to allow for less than 50% of the effort going into driving it. You can change the gearing by altering the length between the rowing bar pivot and the point where the drive side of the chain mounts to the rowing bar. The shorter the distance the lower the gearing. You could make it adjustable. The pivot will be fixed but you could make several mounting options for the drive side of the chain to see which one works best. If you're really clever you could run a rod or cables down the rowing bar and make the gearing infinitely variable, being adjusted by that rod or cables sliding the chain mount up and down.
 
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Ok Unfinished No 1 [ UNF-1 ]



Front of fork with reverse cable entry brake.



rear of fork with suspension fork bridge welded to back with normal cable entry brake.



Added the screw from plate to rear mech to stop it twisting.

To remove wheel just completely unscrew this side axle nut and lift plate of the 2 keying bolts that are screwed through mudguard eyelets and rear mech remains fastened to plate.
Oddly I had to modify mech not something I normally want to do with standard bike parts , however the hole in it was not 6mm [ is now ] and there was a lip on the back helping it stay located in fork slot [ which of course I don't have , there is just a hole ]

Next up cable up brakes and rear mech then we should be ready for a test ride ?
 
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This is sort of interesting ?

A delta rowing trike , a university build I think.


They seem to like chains :ROFLMAO: however it does mean they are applying power to the rear wheel on both strokes.

It has a very very good turning circle !

Another one with cable steering ?

Looking at this again :-



I now realise why it has all those cables and pulleys DOH

They need to be taking the drive from high up the mast to get any sort of stroke and they also need to reverse it.
 
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I can't see the forward stroke adding a lot if anything to the effort in a real world ride. The body simply can't push such a lever anywhere near as hard as it can pull it. I also think that to add anything at all could even detract from the pull phase. I say this because the speed of the row would have to be slower so the push muscles could catch the road speed up to add anything which then compromises the pull stoke where good power can be generated. On the push stroke the legs add very little if anything (the feet would need to be fully clamped to the pedals to allow the legs to pull against them and you'd need a seat with a back to allow the arms to push) with most being done by the stomach and arms. Think how much effort it takes just to lift your own weight doing a sit up and the speed of that sit up versus the speed and power of a rowing power stroke. I'd suggest that unless disabled a healthy person should optimise the machine for the power stroke and accept the push as lost. I can't think of any practical rowing boat that attempts to utilise the push stroke and that either indicates it's a dead end or you're the Archimedes with the eureka moment. I'm not convinced that last machine was built by Archimedes.
 
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Yes I agree , also I think the return is a recovery pause for muscles and breath so useful ?
 
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Update due I think ?

Wooden bike again disgraced itself now chain rides on rear brake lever screws and there is no room to feed gear change cable between front chain ring and wooden frame !

Ok enough is enough , it has been dismantled and throw in the bike shed yet again , maybe in a couple of years time I will drag it out for another go at getting it ridable ? [ I tried to give it away a few years ago without success :-( ]

So wooden mock-up sees the light of day ? Clone [ sort of ] of ZOX 20x20 S -frame



Wood base sits rims about right height from ground [ as no tyres fitted :) ] seat almost 20" as can be seen by level with top of rims.

Wood represents 1.5" sq frame tubing , single side mounted rear wheel so offset from front wheel :) groovy ? or what ...

Wrong front fork need to get rid of axle offset AND move wheel closer to seat to allow pedals to be closer to seat as well.



So question is what are we trying to achieve here ?

a) FWD - should be possible

b) seat height less than PDQ - about 5"

c) my own build 2 wheeler - hmmm

You can see Clox [ clone of ZOX [ neat hey ? ]] as front wheel further forward so pedals must be further forward than PDQ's as I need space for wheel to turn.

Which means seat must be further forward as well.



So question is what are we trying to achieve here ?

a) FWD - should be possible

b) seat height more than Python - about 10" - out the dirt !!!

c) my own build 2 wheeler - hmmm

So what to change I think main frame under seat needs much less slope , so add some height to rear wheel mounting and add some depth to small piece at other end of main frame piece.

If I don't get that tube almost horizontal then seat will become higher as it moves towards forks ?

All for now still pondering Paul
 
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Paul,

It does look like there is a fair bit of "room for manoeuvre" there to make the main keel a bit more horizontal (as you say).
Surprising how high you can sit atop of 20" wheels really. But on a 2-wheeler its quite common I guess.
Keep going, we need to see this progress to a real frame. :)
 
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