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Kimjon's not as cool or epic as Muncie's off-road goped Bigfoot scooter thingy


Kimjon

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Spent the day doing all the tedious stuff, cleaning rust off metal, replacing rusty bolts, springs, circlips...painting...cleaning rust off metal...painting...cleaning rust off metal...painting...

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Lots and lots of little bits.

I did order some cool bike parts off eBay, that I'll use to make handlebars etc...those may take weeks to arrive. But pretty much just waiting on to arrive.

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Goped's have a pretty trick handlebar system that folds down. However  its also a bit of an Achilles heel, as it's most likely the first thing you'll break.

The race peds have fixed poles, much like modern kids scooters have. A race pole landed in nz is going to set you back about $400-$500. Once again, not really an option for me to throw a credit card at...so time to roll up the sleeves and hit the lathe/mill again:

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I made this part...sexy eh! Fuck I love working with aluminum...it just does what you want it to.

I then purchased the coolest of the cool scooter stem clamps. But this was knowingly purchased in the wrong size.

Now to make it the right size took more work than anticipated...but I'll just post some pretty pics that make it look simple:

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Drilled out to 30mm from 28mm. The other half has an ID of 35mm, so it will need shims to bring that down to 30mm...giving full length clamping surface of ID 30mm.

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It took two shims, one inside the other to achieve what I wanted. I did this turning them down on the lathe, then slot milling them fitted one inside the other to end up with the perfect sized shims.

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Here's a mock up with some handlebars on. I won't be using this set... but it's cool to slap em on, stand back 5 paces and visualise.

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The factory bars are only 1mm wall thickness aluminum. I'm going up to 3mm wall thickness for added rigidity.

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24 minutes ago, Muncie said:

I think I like yours better....... liking the alloy deck do they get slippery?

Not too bad.

I made my own (deck) about 20 years ago for this goped sport pictured below:

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The deck has never caused an issue. Although in the wet may be different?

I still have that scooter... and it still hauls arse, with a power band like a sledge hammer!

It was the first motor I ever fully built myself. Its a hybrid with Zenoah G23LH cases and crank, with a Zenoah G290RC head and piston. That's 22.5cc and 29cc with the resulting hybrid ending up at 25.8cc. I gave it a very mild port job, advanced the timing, raised compression, added a bigger carb, made a velocity stack, lightened the fywheel and added an expansion chamber. 

When I built it I really didn't know what I was doing, but somehow fluked a pretty good resulting product.

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I think you have improved on Go-Peds original design with the carb out the back instead of the back of ya leg. Should send them instructions on how to improve their products :)

Similar story with my engine, first set hands on one of the Honda V Twins fitting one to my bosses amphibious boat as a hydraulic power unit. 

I'm still looking for a place to race you..... once the 20cm cut in my back heals it's on! Been on a few test rides and im confident the Death Ped no longer wants to kill me.

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Tv's so boring these days, there's never anything on worth looking at...so I dragged the goped inside to stare at on the off chance I glean some inspiration.

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My wife is currently googling "psychologists in the Waikato region". I don't know why, there's nothing wrong with her?

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I was worried about what could happen if the chain was to break. So I decided to fit a guard.

The guard may as well perform a dual function, so I came up with this tensioner system, that will put pressure on the chain to eliminate any slack.

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I need to get a bearing/roller to complete. But those are easily available.

Now the chain should run sweet, but if it does break it hopefully gets deflected by this and doesn't whip me!

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I took onboard some advice and shifted the chain roller further away from the pinion gear. It now contacts the chain close to the middle of the span between the pinion and the driven gear.

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Its just sitting on there for a quick photo. But you get the idea. I'll finish it off, and sandblast it to reduce drawing too much attention to this part.

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I added a pin on the end of the handle you push to adjust initial tension. This was added to catch the chain. So now if the chain breaks, it's gotta get past the expansion chamber, then the handle pin and the pivot pin on this tensioner. I feel a lot better with all this redundancy.

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Cool, cheers for the tips @Muncie

I got this tensioner mechanism sorted! It's all working as it should, but for now I just have a bit of rubber in place of the chain roller.

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I'll buy a chain roller for a pit bike, I've used these before and it worked great on the other applications.

I'll tidy it up a bit and then call a day.

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Swapped out the rear 68 tooth sprocket for an 80 tooth.

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This should give it more mechanical advantage.

68/7=9.71   or   9.71:1 ratio

Vs

80/7=11.42   or  11.42:1 ratio

I do have a 6 tooth clutch/pinion gear, this would bump it up to 13.33:1 if needed. But I'll try and see first. 

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I got hold of some thermally conductive grease, used for heat sinks in electronics.


Took the head off, flipped the copper gasket rings around...put a thin layer of the grease between each of the outer head mating surfaces (I smoothed it out evenly) and put it all back together again.

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The tooling grooves between surfaces don't transfer heat very well.

Think that should be it for now. Still waiting on my handlebars...but everything else is done.

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38 minutes ago, Muncie said:

Fuck yes! Sounds half way between a swarm of wasps with laser beams on their heads and a huge chainsaw. Don't spare the safety gear on your first ride picking it'll be an absolute handful to ride.

Haha...

Going to swap carbs over to a slightly bigger walbro, as I suspect it may be running lean on the LSN.

The bigger walbro has a dedicated needle jet in a more accessible location to adjust/tune. So that'll be this afternoons mission :-)

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