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Old 04-11-2013, 08:28 PM
Cube26 Cube26 is offline
Motorized Bicycle Newbie
Join Date: Apr 2013
Location: Melbourne Australia
Posts: 7
Talking Newbe 70cc build... FAST

Gday all this is my 1st time on the forms and also my 1st time to build one of these bicycles.
Bit of background info, Im 20 years old, live in the south eastern suburbs of Melbourne near Pakenham. Love cycling and have a good collection of bicycles including Mtbs, a recumbent and some road bikes. I sold my tandem as I had no room for it. Then decided to build a motorized bike, partly due to the fact of writing off my car . I was strapped for cash so I purchased a new $100 70cc engine kit of eBay, but after a few rides wanted more speed so got this shift kit
It was cheap but after a little bit of cutting and grinding it works.
This kit is stock except for some extra mods that I made:
-Installed a 4.5l quad bike tank as the metal ones rust
-New fuel line with 2 taps and 2 filters
-cut a piece of metal and put a rod through it so I can run 2 brake cables off the one lever
-Front shifting as well as rear which allows speeds of 70kmh on flat but also the ability to climb hills around 40o without the need to pedal
-And to sort out the stretching of the chain over time I install a tensioner that keeps the chain tight and also stops the engine moving and reduces the strain of the engine on the frame.

The hardest part with the front shifting due to the lack of space to install a derailleur, so I cut and welded the old one and made it half the width. I also cut up the old front cranks and used it for the sprockets.

Here is the gears im running:
-engine 10T, runs to left side of shift kit 17T
-right side of shift kit 10T, runs to crank freewheel 36T
The gears:
1st- 28T


All in all if you oil the bearings each trip with quality oil and keep a good 2 stroke mix I use between 18:1 and 20:1 this cheap kit is awesome.
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