Home :: PROJECT Jasons Dirt Quad Bike

PROJECT Jasons Dirt Quad Bike

PROJECT Jasons Dirt Quad Bike




G'day fellow builders!

I'm Jason and this is my 70's Mini Bike inspired Dirt track Quad.

It all started with me having gander at some old school Mini Bikes on the Net. I've always thought it would be cool to have one, but after seeing how much the kits cost that was the end of that! Anyway I came across the Scratch build Grasshopper ATV plan for $15. So I downloaded it and started my project with a trip to Brisbane Metal market for $40 of 25x25x2 steel and started the frame. As I race a 4 stroke dirt kart at Ipswich City Dirt Kart Club, I had a quite a few kart parts that I was able to put into the project to beef it up from what the plan had suggested in places.

The engine came from an old 196cc clone pressure washer the Guy across the road had out for Curbside Collection. So under the cover of darkness I slipped over and grabbed it. So, I pulled it down and rebuilt it with old race parts I had laying around. Flat top piston, a race retired 28mm valve head with a 50 tho shave, 10 thou billet rod and Raceseng S2 Billet flywheel and a set of Raceseng 1:2 roller rockers. At the moment the cam is still stock because my racing ones have the compression release removed. Will be looking to use something with a 275 ish lift in the near future. The carburettor is a self bored (16.5mm) and reworked genuine Honda running e85. It also uses a manifold spacer and a ARC velocity air filter  adaptor. I also decided to go with a Tav2 torque convertor so the gearing covers a wide range for all different riding conditions.

Regarding the rolling Chassis, The rear end is a complete CPR 40mm axle set up with Diy bearing hangers. The rear calipers are from CPR too. The rear shocks are adjustable coil overs from ebay. The rear rims are Edwards Speedway 175mm x  6 inch diameter. The rear tyres are Unilli 225mm x 6 inch. After a long search for ideas regarding what to use for foot pegs, On the net I came across people using wide platform bmx pedals on Harleys. So I took that option and they work great!

The front end is a complete CPR set up, with the swing arm support rods being CPR tie rods and ends too. The front wheels are just cheap Ebay 13x5x6 atm, hoping to upgrade to 6 inch Speedway set up in the future. Both upper and lower camber adjusters are CPR along with all nuts, bolts and washers in the front end. The front shocks are the same as the rear but with a higher spring rate adjusted into them. The front crash bar was inspired by me watching a Rat Rod build show on Telly.

On top of the Chassis I have a 19 inch old school Deltec Mini Bike seat. The fuel tank is a 3 litre one from a motorised push bike. The Handlebars and risers are from Ebay and the head stock is a peice from an old billet engine mount which I cut down. The throttle and brake master cylinder is from Ebay too.

Ok, how does it go???.
At this stage because it really needs a new cam and im going to need to take it somewhere to let it rip properly, I've only covered the categories below.

Standing start wheel stands are covered!
Ripping the top off the lawn with cyclone donuts are covered.
Long Speedway style, getting abit close to the colourbond fence power slides can be ticked off too!

That about covers it I think. I hope you have found my build as interesting as I've found the other builds on this site. Just like all the other builds I cannot thanks Paul enough! The quality, price and service he delivers is what allows me to enjoy my Racing and Projects to the level I do.

 UPDATE 7-5-2019

Jason has tweaked his Quad!  Check out the updates below:

Find out more about Jason in his Driver Profile