Fat SWB started at last

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The guides are intended for a derailleur but have their own bearing unlike any other derailleur I've ever pulled apart. Maybe the better derailleurs have them?



I'll admit I hadn't considered the swap from return to drive side of the chain with the resultant extra forces. I have seen these incorporated into other people's builds on the drive side but that doesn't mean they didn't make a mistake too.
Yes I understand whilst you see things on the net you have no idea if they broke after 1 mile or 1000 miles ;)

The rule of thumb [ if there is such a thing ] is that the diameter of the drive side pulley should be greater the greater the angle the chain goes through [ the forces are greater and that means the drag is greater ]

So FWD twisting chain bikes may have a pulley of 4-5" diameter.like this :-


Your chain change angle is less so you should get away a smaller pully , but IMHO those derailleur jockey wheels were never intended for those forces.

Have you found this thread ?

Converint stick bikes to FWD

Might help ?
 
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Link doesn't work but I found it via pasting the link to google.
On mine the drive side is moving off line about 30 degrees. Some of those must be nearer 130 degrees. I'll have a think and a look around the web for an alternative.
 
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Link doesn't work but I found it via pasting the link to google.
On mine the drive side is moving off line about 30 degrees. Some of those must be nearer 130 degrees. I'll have a think and a look around the web for an alternative.
Sorry corrected link.

On way is to remove the pawls from a single speed freewheel , add some side plates to stop chain coming off [ needs a chain keeper across side plates as well ] then weld a BB cup to frame and screw it on could still use existing for return side just mount BB cup either ahead of behind existing ?
 
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Steering done. Plenty of room for knees but somewhat awkward to get on and off. I may need to lower the rear end so I can sling my leg over or step through somewhat easier than at the moment. Either that or put a Q/R hinge in the steering column which is a more realistic solution IMO. There's one I could take off a scooter but it's the usual horrible flat type folding hinge and I'd prefer a neater solution if possible. All other types I can find though don't lock sufficiently for the task so the horrible flat one it may well have to be.

 
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Steering done. Plenty of room for knees but somewhat awkward to get on and off. I may need to lower the rear end so I can sling my leg over or step through somewhat easier than at the moment.


I think the angle you have for the hand rests is all wrong and it is them that stop you mounting and dismounting ?
The above I find comfortable and safe to ride with , I can measure there angle if you like ?

Either that or put a Q/R hinge in the steering column which is a more realistic solution IMO.
It's a personal thing but I HATE folding steering columns , I never feel fully in charge of the bike when riding something that folds ?
e.g you brake even moderately hard and subconsciously you brace yourself against the column to hold your body into the seat ? instead the column just moves ahead of you and lets you rise out of the seat ?

You try to manoeuvre the bike and again you push on the bars to move the front part of the bike and again they collapse.
In my world it only adds some uncertainty as to what will happen in a given situation and don't forget it could be your life at risk when the bike does not do what your brain tells you it should for a given action .

Lecture over and good luck finding a solution you can live with ;)



Also your bars look to high for you to see over them with such a laid back seat ?

The seat back of the one I pictured is about 50' and the bars are level with the top of the seat ?
Your seat is laid further back so your head is lower and the bars are higher ?
 
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The angle of the bars is very natural from the seat with elbows at the side and hands in a very neutral orientation. If you think about it, the more you lay back the higher the bars have to go in relation to the seat as your shoulders are moved progressively further away. The bars have to follow the arc of the seat to a degree. Going the other way the bars get lower as you sit more upright like a typical mountain bike with bars on a plane with the seat. What I may do though is run tubes from 2/3 up the column to the top of the held portion of the bars and cut away the top part of the column and the bars which would help vision.
 
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I altered the bars today. As I said I cut away the top part of the column. I also moved them slightly further forward and angled them. I can now get on and off via the expedient of tilting the bike somewhat.



I've also got hold of 4 of these:-







Finding pulleys with flat bottoms at a reasonable price is like the search for the holy grail. Plenty of U channel ones but few flat. A single speed chain sits perfectly in these and a multi speed is perfectly fine too. This is the single speed:-



I'd have liked the pulleys to sit closer but their flare out to the bearing prevents that. Not perfect but I can live with it. The real downside is the M15 inner bearing requirement but a set of 15mm to 12mm front axle converters have been ordered to get it down to a more reasonable M12 not to mention the unicorn-like availability of M15 bolts. These were £11 for 4 from Amazon. I'll get these on tomorrow. After that it'll be a wait for some weld on cable guides coming from Poland with my seat for the next trike on the to do list.
 
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Finished off the chain guides and added the cable management. About all that's left is to pull it apart, give it a good going over with the grinder and wire brush, give all welds a final inspection and paint it. I've not much chance of painting it in winter so I've parked it inside the house to keep the rust away and will come back to it in spring.

 
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