A new trike chassis

I posted my new recumbent a while ago. Quite happy with the outcome, just a few niggly bits I'm not happy with, this new chassis addresses these:

The quality of welds was the biggest niggle, they just don't look good so that was my first concern.

I neglected to place stops on the kingpins so if I turn the wheels enough the tyres actually rub my hands.

The squab angle isn't right so I tend to get a sore bum after an hour or so.

Not enough lumbar support.

Neglected to provide mounts for a rear carrier.

At 5 degrees the camber is too much, placing a lot of strain on the spokes.

Adjusting toe in is a fiddly process.

BB is a little low for my liking.

I ride over a few gravel roads so the trike could use suspension.

Rear wheel tends to slip on loose, uphill sections of road.

The steering levers are a bit too much of a reach for comfort.

With these few bits in mind I decided to make a new chassis.

I have chronic PsA which severely affects the use of my hands, welding in particular suffers so I set about welding the chassis is a sequential manner. Quite happy with the outcome, very little to no filling/covering is required.

I've made new kingpins with cutouts for steering stops. No more black knuckles.

I increased the angle of the squab by a few degrees and put a bit extra lumbar support into the seat back. Extremely comfortable now but only a test ride will tell if I got the squab angle right.

I've welded supports for a rear carrier this time and also included a bracket for a drinking tube so I don't have to use my hands.

Camber is now around 2 degrees in lieu of 5 and the track is increased by 25mm.

For toe in adjustment I turned up a barrel with right hand thread one end and left at the other which the tie rod threads into. Now it's just a matter of turning right to decrease or left to increase then tightening the locknuts.

The BB is set at 340mm, 40mm higher than the original.

I was going to suspend the seat but the weight was simply too much so I settled on rear suspension only. As well as shocky preload I also have nine settings to choose from. Overkill, but!

I've moved the seat closer to the rear wheel and moved the front wheels forward by around 40mm. Hopefully, that should help with rear wheel slip.

The steering lever brackets have been stretched around 25mm rearward for a more natural arm position. As usual I've welded cable guides at various points around the chassis to keep the cable runs neat.

The lever steering on my current trike was an experiment to see how well they worked, if at all. As it turned out, lever steering has proven far superior to USS so I decided to stick with it. Lever steering is superb in comparison to any other systems I've used before.

Seat height is up by around 60mm, 30 with me seated. This works out well, the old chassis had a seat heat of 190mm but, this presented a few problems getting my weary bones off the thing. The extra 30mm or so has made all the difference. Despite the front crossbar being moved forward thus moving my feet forward, the extra 30mm or so in seat height enables me to get off the thing quite easily when stationary. With the current chassis I have to be moving forward, then apply the brakes to dismount, the forward motion followed by a sudden stop propelling me from the seat.

Here's a few pics of the build, just need to add steer lever brackets and it's done.

Looking good Tony. Looks like your welds have improved also.
Kryn

Yes, the welding on this trike is reasonably good, happy with it: no inclusions, no holes and reasonably straight runs: good rods, setting up properly and being comfortable have all proven worthwhile. even had some slag peel off, haven't had that since I came down with PsA.

I wouldn't try some pf the welding I used to be able do, that's all gone by the wayside I'm afraid, it is nice not to have to grind every single weld.

Sorry, doubled up post.

Getting there: undercoated and waiting for the top coat. Metalic silver chassis, Black for seat, rack and steering bits. Alloy bits will be blasted and clear coated.