New trike build - Goanna!

[Freddyflatfoot]

Ok, its been a busy week!
Got my daughter's trike up and running, and tonight I finished, well, got my new build up and running.
Her name is Goanna, and by the feel of my short test ride, she should be quite quick!
Dunno if I can post links yet, but i'll give it a go, and see Goanna in all her raw glory!
http://s281.photobucket.com/albums/kk20 ... a%20trike/

Ok, so I haven't been here for 7 days!
so try and do the xxx=www, yyy=com thing and you'll get the pics!

(Edit: link activated by mod)

[Storm]

Wow that is fantastic Rob!!

Looks like a very clean machine with the rear stays like that, I hope theres enough strength there. How did you join the crossmember, is it just welded to the main frame or have you also used a strengthening brackets? Love the front hubs too, looks very nice, What are the rails behind the seat? Does the ply need extra support? Can you show a close up of the seat?

Another link... the schools in Australia racing the HPVs have a dedicated forum with tons of trike info.... PhantomHPVs

BTW hows the LiFePO, I hope you havn't had any trouble from it? The 48v pack I got has been a PITA three completely dead cells, faulty BMS etc, I'm still waiting on replacement parts, I still have the other 24v pack which I intend to use for my next project...an electric lowracer.

[John Lewis]

G'day Freddy F,

Your trikes look great . I'll bet your daughter is tickled pinkwith the trike you built her.
I always enjoy looking at what other builders are doing.
Always amazes me what can be done with mild steel and a welder.
Are you using a stick welder or MIG ?

Atomic Zombie is an interesting site for bent plans. Timothy Smith's site is interesting too. I've ridden one of Tim's trikes and it performed well.

John Lewis

[Freddyflatfoot]

STORM
Crossmember is 'mitred' into the main frame, using a fish mouth type of fitting into the main boom, about 1/3 rd the depth of the crossmember, and then welded all around. Should provide enough strength, and resistance to side and twisting forces. I found that a straight butt mount on my sq framed tube wasn't quite strong enough, and ended up adding gussets.
On Melissa's trike, I notched the crossmember into the main boom, so should be plenty strong enough.
with the seat, I basically used the same method as my SWB, and used two sheets of 3mm ply. felt is was nowhere stiff enough, so added the 12.7mm sq tube bracing to add the stiffness. Also adds a fair amount of extra weight, but you can't have everything!
The SWB has done about 1200 k's, and the seat is holding up very well, so decided to make these ones the same way.
I'll try and take some pics of the seat when I take them off to paint them. I just covered them today with some blue camping mat. Not totally ideal, but should provide enough padding.
I'm expecting that the rear stays will be strong enough, the stays are 31.8mm wide x 12.7mm, and 1.6mm thick, and the tube is also 31.8mm x 1.6mm, and welded into the main tube using a fish mouth, so should provide enough strength.

Thanks for the link, I'll have a look later.

The LiFePo4 is in 'hibernation' ATM, but were working very well! The MTB has been dismantled so the motor/pack is not on any bike. I have a 36V motor on my trike, and got a duct tape 36C/10AHr pack, which is working very well, but i did have a BMS die, which was promptly replaced. Thanks Ping! I would like to make up something to use the 24V pack on, possibly a Cyclone recumbent specific motor, either 380 or 500w.
I hope the lowracer works at well! The only way I wanna be that close to the ground is on a trike!

JOHN
Thanks! daughter loves the trike! And I used a stick welder, using 2.0mm rods.

The site that gave me the most inspiration when i started building, was Fleettrikes dot com.
Although I did have a good look at Atomic Zombie and Tim Smith's site.

[John Lewis]

Thanks for that welding info Rob. Don't know how you do it. I've not had much luck with a stick welder on thin stuff. Mind you, it's a cheap Bunnings one and I've never had any lessons in arc welding.

I do all mine with oxy and bronze rod as I found I'm quite good with that.

For your interest, the cantilever chain stays on my Bentech SWB are 25mm by 1.6mm round ms tube and have been fine for several thousand km.

I've used the same setup on a trike but not canti as I braced it with the mesh seat frame. I've used mesh on nearly all my bikes.

You can see the trike I'm doing in this forum thread " New Trike Taking Shape. A few mods since then. I Angled the main boom to get more pedal clearance and a bit more trail. Will get some more pics up shortly.

John Lewis

[Freddyflatfoot]

John,
Did I say I bought a $99 welder from Bunnings?
I've tried brazing, but not good at it! maybe I'm not getting enough heat using straight MAPP gas? Anyway, I still braze on the small fittings, like cable stops.
Thanks for the info on the Bentech chain stays, makes me feel even more confident!
Just got small stuff to do before I strip her down and paint her, might even have a look at powder coating!

[Freddyflatfoot]

Took Goanna out for her first 'shakedown' ride, about 14 k's in total.
Here are my thoughts;
WHAT I LIKED
She's low to the ground (9 1/2" seat height), and fairly laid back (about 36 degrees), but not too far. the seat is also nice and firm.
Acceleration is quick and brisk, and handling is sharp! She felt quick, but no speedo at this stage, felt like it could be fairly comfortable in the 30 - 35 k range, but that's to be confirmed once I get the speedo fitted.
Brakes are good! I really like these SA drum brakes, nice and progressive, but can really stop in a hurry if you need to. The park brake levers I got are a worthwhile feature!
The frame feels nice and supple. Just enough passive flex to increase comfort. Could also be the 26" rear wheel, with the Maxxis Overdrive tyre mounted.
The cantilever chain stays seem to be rigid enough
WHAT I DIDN'T LIKE
Can be a bit skitty at higher speeds. Steering can respond quite quickly to small steering inputs.
The 170mm cranks I put on, really don't like them at all!
The flat pedals I put on. My feet were all over the place, I really need to put on some clipless pedals, but then I just put these ones on for testing! They had toe clips, but I couldn't get my feet in at all, they hang the wrong way.
No mudguards! The weather decided to turn nasty while I was out, and started bucketing down. I got a real drenching! The water coming off the front wheels is a real PITA! I suppose I got some on the back of my head from the rear wheel, but I dunno if I really noticed!
Possibly a bit too narrow, on really tight turns, the wheel will rub my shoes. Track is about 25".
WHAT NOW?
I'll try and put up with the 170mm cranks for the time being, but I can see some shorter cranks in the near future!
Put on some clipless pedals.
Weld on a light/speedo bracket to the derailleur post and mount front light and speedo. Mount rear light.
Buy and mount a rear rack, to attach my panniers, for day trips etc.
OVERALL
I like this trike! Dunno if it will be as fast as my SWB, but I reckon she might come close! She looks good, nice and low and sleek, and should look really good with a lick of paint! The hard shell seat was a good choice, and I have some 50mm filter foam coming.
Did I say I like it?

[Freddyflatfoot]

Just a quick update on 'Goanna'.
Stripped her down, and cleaning up all the welds etc, ready for painting.
Too cold to do it myself, so got a quote from a panel beater mate, to paint the frame for me.
I figured if I'm going to pay someone to paint it, I might as well get something a bit different!
Two colours are vying for attention, and that is the Ford 'Citric Acid', and the new Holden metallic green, 'Atomic Metallic'
At this stage, I'm leaning towards the Atomic metallic, if I can get the paint!

[Uba Tracker]

John,
Did I say I bought a $99 welder from Bunnings?
I've tried brazing, but not good at it! maybe I'm not getting enough heat using straight MAPP gas? Anyway, I still braze on the small fittings, like cable stops.

G'day Freddy, good job on the welding mate, I spent twenty four years as a welder and in that time I've managed to use just about every welding process there is and without a doubt stick welding is the hardest in terms of achieving satisfactory consistent results. If I was to make a judgement call for the best allround process for the home bike builder I would vote for brazing every time. The flexibility of brazing allows you to do every joint with the one process, there's no way cable stops can be glued on using arc/stick welding, they'd get vapourized. Like any skill practice is the key and if you can get a bit of advice along the way it'll help a bunch. As far as heat input is concerned you can braze with OXY/LPG but you can't fusion weld, OXY/ACETYLENE will allow you to braze and weld if you want. Try not to overheat the job otherwise you'll burn the brass off the job and make a mess at the joint area, brazing's only real limitation is that it's not a great gap filler so spend a bit of time to get the fit nice and neat. Once you get the hang of it you'll find that there is little or no clean up of the weld(braze) area aside from a bit of flux residue which will fall off of it's own accord in a day or two anyway, boracic acid will clean it up straight away if time's against you. Sorry this is a bit long winded but I still love welding and it's great to be able to pass on some tips.
cheers
Harry