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The weather has stopped play on the Drypod as I need to be outside to hinge the body up and down (the big disadvantage of a tilt body) so I've committed a cardinal sin and started my next project. If I get this right it will be a tilting tadpole along the same principle Alan Maurer built his. It will use caster as the steering mechanism in that a heavily castered wheel will steer when tilted. Steering and tilt will be separate functions though in that it'll be able to tilt without any steering but the opposite is not true, ie it can not steer without tilt. Here's a video of the inspiration.
This will be my mk3 as no.1 was a complete failure and scrapped and no.2 was my green one which works fine but on different principles. Progress is somewhat limited in that all I've done so far is to sort the rear end for it. The swing arm came to me as an unknown Whyte unit as part of a deal and languished in my pile for years. It weighs almost nothing which is why I want to use it. On looking for a dropout for it it became identified as a Whyte JW2, made about 20 years ago and attached to a very low volume forkless mountain bike. Even Whyte don't sell the dropout any more - marvellous. On scouring the net for anything similar it appeared a Marin unit may fit and £21 later indeed it did. Quite why Whyte don't say this on their website when Whyte and Marin are under the same company is beyond me. The pivot on this is a pair of real actual bearings - a first for me. The bearings in the arm were of course seized so I pulled them out with the time honoured trick of a bolt and socket. It turns out they are imperial which surprised me given I believe they were made in the UK. By a stroke of good luck I had several such bearings I'd been hoarding for years on the off chance I'd ever need them so pressed them in. This is why you never throw anything away. A mount to the chassis would be needed and I've used some 1" 16swg tube as a bearing holder with some 3/4" tube in the middle to seat another pair of the same bearings against and a pair of oilite flanged bushes at the outer edges to help rotation and protect the swing arm. It all slotted together nicely to make the mount.
The swing arm origin.
Somewhat odd dropout needing bolts to hold it in. I need some longer bolts.
The parts for the chassis mount
And assembled and in place
Sufficient room for a 10 speed freewheel
The brake mount utilised a front 160 to 203 adapter wrong way round and with an extra hole drilled and tapped into it. I have no idea what those holes are originally for in the swing arm. Clearly they are not std disc brake mounts and they are replicated both sides. At a later date I'll kiss the adapter with a flap disc to de-blue it and grind the spare hole off.
The rear brake will be very much needed on this unlike many tadpoles. Applying the front brakes means that the steering mechanism wants to steer further as you brake as the caliper mount has to be attached to the caster arm. This desire to steer further has to be resisted by the rider applying pressure against the bars. Not ideal but pretty much every tilting taddy I've ever seen has some compromise.
It's not much to show for 3 hours work but you have to start somewhere. The chassis will be built from round stainless and I have a stainless reel for the MIG. Yes it'll be a pain to work but most of that work will be done with powered tools such as a chop saw. I'm hoping not to need to paint the bulk of it. Certain parts will need to be painted such as the rear swing arm mount which is mild. I do expect to need to dry it after any rain and oil it regularly. This won't be a daily rider though so such demands can be accommodated for the sparkle provided. If it does start to rust I can always paint it later.
Next job will be attaching the main beam to the swing arm. I have a 1" drill so will see if I can get that through the 45mm tubing to slot that swing arm mount through. I expect that to be my first cursing session against my stainless choice.
This will be my mk3 as no.1 was a complete failure and scrapped and no.2 was my green one which works fine but on different principles. Progress is somewhat limited in that all I've done so far is to sort the rear end for it. The swing arm came to me as an unknown Whyte unit as part of a deal and languished in my pile for years. It weighs almost nothing which is why I want to use it. On looking for a dropout for it it became identified as a Whyte JW2, made about 20 years ago and attached to a very low volume forkless mountain bike. Even Whyte don't sell the dropout any more - marvellous. On scouring the net for anything similar it appeared a Marin unit may fit and £21 later indeed it did. Quite why Whyte don't say this on their website when Whyte and Marin are under the same company is beyond me. The pivot on this is a pair of real actual bearings - a first for me. The bearings in the arm were of course seized so I pulled them out with the time honoured trick of a bolt and socket. It turns out they are imperial which surprised me given I believe they were made in the UK. By a stroke of good luck I had several such bearings I'd been hoarding for years on the off chance I'd ever need them so pressed them in. This is why you never throw anything away. A mount to the chassis would be needed and I've used some 1" 16swg tube as a bearing holder with some 3/4" tube in the middle to seat another pair of the same bearings against and a pair of oilite flanged bushes at the outer edges to help rotation and protect the swing arm. It all slotted together nicely to make the mount.
The swing arm origin.
Somewhat odd dropout needing bolts to hold it in. I need some longer bolts.
The parts for the chassis mount
And assembled and in place
Sufficient room for a 10 speed freewheel
The brake mount utilised a front 160 to 203 adapter wrong way round and with an extra hole drilled and tapped into it. I have no idea what those holes are originally for in the swing arm. Clearly they are not std disc brake mounts and they are replicated both sides. At a later date I'll kiss the adapter with a flap disc to de-blue it and grind the spare hole off.
The rear brake will be very much needed on this unlike many tadpoles. Applying the front brakes means that the steering mechanism wants to steer further as you brake as the caliper mount has to be attached to the caster arm. This desire to steer further has to be resisted by the rider applying pressure against the bars. Not ideal but pretty much every tilting taddy I've ever seen has some compromise.
It's not much to show for 3 hours work but you have to start somewhere. The chassis will be built from round stainless and I have a stainless reel for the MIG. Yes it'll be a pain to work but most of that work will be done with powered tools such as a chop saw. I'm hoping not to need to paint the bulk of it. Certain parts will need to be painted such as the rear swing arm mount which is mild. I do expect to need to dry it after any rain and oil it regularly. This won't be a daily rider though so such demands can be accommodated for the sparkle provided. If it does start to rust I can always paint it later.
Next job will be attaching the main beam to the swing arm. I have a 1" drill so will see if I can get that through the 45mm tubing to slot that swing arm mount through. I expect that to be my first cursing session against my stainless choice.
