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Kimjon's resurrection of Pete's wajax velo bike


Kimjon

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oh boy bicycle spoke yarns

 

if the rim is single layer then i would trash it, hopefully its got eyelets for the spokes. looks to be a 32 spoke rim. 36 would be better, 42 would be ideal

you can decrease the probablility of the spoke tearing the rim and the rim cracking by running spoke washers. dont get bicycle ones, just get tiny washers from an engineering place

 

you could replace them with stainless spokes, i would go for straight gauge, tie and solder them for extra rim stability too

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Oh Christ! Didn't realise the spokes would be under so much stress.

My thinking was a wheel designed to be stoped by disc brakes should be strong enough, as rapid deceleration around the hub is equal and opposite to acceleration from a motor?

Usually braking produces more torque than accelerating does. But the top end speed and weight of the bike has increased in this case...dam it...now I'm concerned.

Has this scenario shown up in previous velobikes? Is it common to rip spokes out of the bicycle rims?

Kj

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i vote use some spoke washers and monitor the hub flange and spoke eyelets

 

disk brakes are alot harder on spokes than a rim brake

 

 

spokes are kind of expensive if you need to change the lenghts, bout you could consider changing to a 4 cross pattern if the number is right.

If you want i can bring my wheel stand, dial gauges and spoke tension tool down to hamilton, and we can improve the wheel over the machine built spec, itl last better that way, get the tensions right and you dont have uneven stresses

 

iv destroyed a wheel with a 50cc 2 stroke attached to it, it snapped the spokes at the elbow. it was a 50 year old wheel though (built really strong but probably alot of wear) and have torn spokes out on my touring bike.

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Dude, that would be fantastic! Don't go out of your way, but if you're down this way sometime in the near future (10 minutes out of Cambridge) I'd love to get some expert opinion.

Its a cheap wheel, so I do have concerns. I YouTube'd wiring and soldering spokes. That looks like a great idea too.

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And a battery box.

 

IMG_20170519_115643_zpsglxwihmz.jpg

Cut about 100mm off its overall length, then cut out a hole out for the battery to sit in. I'll wrap fuel line around the sharp edge by cutting a slit on the outside edge.

IMG_20170519_122646_zps5gi4lkqm.jpg

Welded together. Welding has never been a talent of mine, but I own a grinder!

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Mounted to frame. Its removable so I can get battery out. 

IMG_20170519_141022_zpshmghebrl.jpg

IMG_20170521_083616_zps2dhviwse.jpg

Kj

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  • 2 weeks later...

Any reason why this won't work? The hub still free wheels, is this good or a bad idea?

IMG_20170527_175609_zpsss0kqolz.jpg

I haven't welded it to the other sprockets yet, but that should hold it fine. More concerned about the strength of the two dogs that lock the hub up when torque is applied. Maybe I'm just over thinking everything now?

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Common on mountain bikes and touring bikes, bang  a 100kg cyclist on a 170mm crank and you have some decent torque.

The drive dogs are pretty strong the only issue is them not reengaging when you throttle off. You may even flush the grease out and just use oil instead

 

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5 minutes ago, tortron said:

Common on mountain bikes and touring bikes, bang  a 100kg cyclist on a 170mm crank and you have some decent torque.

The drive dogs are pretty strong the only issue is them not reengaging when you throttle off. You may even flush the grease out and just use oil instead

 

So you go for it eh?

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The only issue I see is it not re engaging at speed after throttle off

 

So keep twisting? Haha

 

I mean to say, a huge cog can be fitted for super low gears on touring and mountain bike clusters. Usually you remove the smallest and repack it. Never heard of one failing. If you chave the option I would bang in some prongs/grub screws to locate the cog and assist the weld

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Through the magic of the internet, a cvt appeared in the mail today. This was a tad exciting, as up until today I've never actually seen one in person.

IMG_20170531_134439_zpsmzjpikfh.jpg

Now the wajax motor on the bike is pretty fucked.  Pete has raced it along the beach (that would have been fun!), unfortunately the salt has got into every crevice and caused severe corrosion to both metal and aluminium.

However the silver lining to this situation is there was a second incomplete parts motor included...so fingers crossed I should be able to cobble something together out of the two?

I "test fitted" front driven pulley of cvt on second motor, and it's going to fit with a bit of work done in the milling machine to square it up.

IMG_20170531_134408_zps8dcjnsh5.jpg

The cvt is a big mother!!! I up-sized my combo and got a 40 series not realising the physical size of it. Hopefully it doesn't bend the crankshaft with all that weight hanging off it? Like everything else in this build...try and see i guess???

I mocked it up using a plywood template to check clearances, looks like it should work.

IMG_20170531_143036_zps991kxkxj.jpg

 

IMG_20170531_145511_zpssg9igcz2.jpg

Down tube will be tight, but I think with some creativity I'll find a solution for that. After all we want "no problems, just solutions"!

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Stupid amount of effort going into this project, but it's kind of fun bodging together cheap parts to make something cool.

Seat arrived today all the way from China. Fucked if i can work out how they can only charge $17 for a leather seat including free postage from another country door to door?

Anyway:

Seat stripped down, set back pivot made up and fitted

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Seat posts with a M8 captive nut in each. Plus pivot front mount.

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Test fit

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Hmmmm leather...sexy!!!

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Going to swap the leather on the tank to match. Will try simply sanding it first...nothing to lose trying that. But otherwise, back to the $2 shop to get another belt.

 

Edit:

Easy fix on the tank leather, simply turn it the other way around. I'll lacquer it another day to match seat.

IMG_20170603_161847_zpscf80paoa.jpg

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Today I had McDonalds for lunch, WTF does that have to do with anything? Well it cost me $21 for a coffee, fancy chicken burger and an M&M McFlurry... $21 dollars!!!

Half an hour later I purchased a leaf spring for a trailer, brand new, made of real steel...$22.

Hard to believe that both items cost roughly the same, my only fear is that I turn both purchases into shit? But life's boring without a little gamble every now and then, so here goes nothing:

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Cut with angle grinder, left purposefully oversize for now.

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Mocked up for size...yip, too big, but that's an easy fix.

Will roll with this idea and see where it takes me.

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I think I've got my head around it now. I only had an hour to play with it today, so made up a bracket and bent up some rod.

IMG_20170610_163423_zps2h1wordn.jpg

Then I jumped back onto the cvt connection to the motor. It had an internal keyway, so I milled a slot to receive this on the output shaft.

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Im not 100% happy with the hollow aluminum output. I have my doubts it will be strong enough...but if needed I can turn up a steel version later to the same dimensions.

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