Project "Stealth Mode"

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Aug 27, 2022
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My beloved Dunlop F6 Typhoon, was an entry into the triple threat BO last year but I forgot to post the final pic Grrrr, So it then it got a repower in the form of this 100cc 2 stroke Flea bay motor kit!
Without checking first the bike was modified, I then discover my state of Queensland forbids the use of any bicycle or tricycle on the road or national parks , bikeways etc, if it has an internal combustion engine fitted! PERIOD!!! no exceptions etc etc...Blanket law covering all base's... electric however is all good, dont even ask what the mentality is here but an electric bike can go twice as fast as a petrol bike but who are we to argue. So there it is! ive now got this great bike that...while not fast , is quite cool n different, and i love it!
So what we do now is ...... No not sell it..... not remove the motor..... we.....Hide everything! i'll use the provided pic to reference before and after, i'll take the bike to this exact same spot and we'll see if I can pull this off! all that has to happen is I ride past the cops and they think this is not a petrol bike! thats the goal here! even though I may be lucky to see 1 cop every 20 rides , on this bike it will only take 1 encounter where I receive a $250 fine,

Mission......... to make this motorised illegal petrol bike LOOK like an electric bike!

Step 1..... Modify exhaust pipe and muffler to run parallel with the down tube!
So I dont muck around when im keen on a project, chopped the exhaust off today, Its important to cut then shape and tac before actually removing the whole exhaust pipe, I always try and leave as much in place as I can to check angles , lengths etc.

I only had to add a couple degree cuts to each end and turned the pipe about 1cm, threw a couple welding tac's on it and removed then welded it all up.
I was able to inspect the inside and gave it a light sand, no welds went right through and blobbed, which is a big no no when doing an exhaust for anything!

Refitted everything came together perfect! small but adequate clearance between frame and Muffler!


I havnt upset the curve in the exhaust pipe too much. over the moon it only took the single cut and turn to get the thing where I wanted! i'll re-modify that support strap so it fits better in the new arrangement. and those big GT pedals that were meant for princess harry .... well they didnt fit so they ended up on here!


Thats it for now, after the Hardware stage is done I have to make some tricky covers to go over that exhaust and muffler, the motor etc, all have to be hidden..... some how LOL!
But weve managed to change the exhaust profile so from a distance its now blended in with the frame, If I can get the cover for this to look good enough it will look like a lower battery box.....well from a distance sort of...???
Anyway....NEXT....the tank!!!!

Ok so with the end of the build off i can now get back to this!
I started by replacing a couple parts that got robbed for "Direction Unknown" the front tyre and the seat!
Note in this pic you can be right on top of the bike almost and the muffler is almost gone!

I started to cut these old mounts off, they were used on a demo project months ago where I had a set of mtb forks welded to the rear dropouts on a bmx, I had a spring at the front of the seat and these mounts were for that!, I started up the grinder but remembered the daughter was on a video conference and her room is within ear shot of the shed! so i'll do it a bit later!

So I put the wheel back on with its tyre too, pumped it up and really really wanted to ride it , so I put the seat on unmodified and took it for a blast!, ive now set the the cogs to middle front and smallest rear, a good heavy gear to pedal easily when underway with the motor happily assisting, she went great! and it was another stunning day here!
Thats concludes day 2 of "Project Stealth Mode"
ok so after a mammoth wait the new tank has finally arrived!, it was only $10 and only holds a litre,
You can see by removing the tank it takes an awful lot, visually ,away from the bike.
The small plastic tank now resides up n under the seat, I still have to modify the tap, filter and line a wee bit but the general idea is underway!
if you can imagine it ...there will be a "FAKE" tool bag covering the new fuel tank, breathable and easily removable to refill etc!
So While looking at this pic, try to imagine the tank as a black tool bag under the seat, the motor and carby set up will be covered but ill leave the round crank case visible, it will look like an electric motor of some sort! did I mention the cops have to be almost deaf to get away with this LOL
A bit more on the tank mounting!
I used an old guy spring from our camping days, I pulled it apart and bent it to shape so it would fit around the seats rail underneath, then hook up to the side holes in the tank, and hold it steady with a reasonable amount of movement!

It turns out it swayed a bit too much so I used and old ally carabiner clip and tied it to a cut up piece of bike tubing and tied the other end to the seat tube on the frame, held it firm but not clamped to death! you can see it in this particular pic but the tank is mounted with a slight biased towards the outlet.
Remember this eventually will look like a tool bag of some sort.


Tomorrow i'll move that filter up and above the tap to get rid of that kink and stop the air bubble, I took it for a 2km ride today with no visible loss of fuel , even though small this tank will be more than adequate for the amount of riding this will get....which is very little ha ha ha probs be looking at 20km max range in a tank ,if anyones wondering I use a marine grade 2 stroke oil with my fuel, most marine oils are blue so the fuels is easily identifiable! ita high grade too, was $110 @4 L, I use it all my other stuff that needs 2 banger fuel only!


I wrapped a black rag around the parts im trying to cover so you can sort of visualize what im chasing. see how i'll leave that rounded crank cover to look like a small electric motor!
Remember, the object here is to fool the opposition from a distance, like the other side of the road or at an intersection, if the cops get to the point where they are actually talking to you then you may as well get your wallet out there and then LOL. im trying to trick them so they continue on thier way to doughnut king and grab a coffee bundle!
Also hot wheels sitting on the stand waiting for flea bay parts.
Anyway that my friends will be the conclusion of day 3 on "Project Stealth Mode"
Very late update, this project will end here, the son is now big enough to ride it, it was a strange thing happened, some feral kids down the road had one and he saw them getting around on it, it was the quickest turn around ever, from walking past the bike and completely ignoring it to sitting and just looking at it,
I still have to start it and warm it up, there is a process for that, but I can see him thinking, he’ll be 14 soon, great time to let them spread the wings a bit,
The gathering of a herd of kids… works every time.
So dad being himself decides to have a turn and after reminding the young bloke to keep peddling wide and dont let your legs hit the engine,
This happens to dad 😂😂😂