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Nos And Pocket Bikes.....


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yeah i had a 49cc pocket bike with drilled out jets in the carby little pod fillter lighten flywheel racing reed valve took the top ring of the piston to drop the compreshion and made 1 of those electric turbos they sell on ebay had exspanshion chamber really high gearing had a little 12v motor bike battery bolted up to it so i could run the charger man and it went pretty hard hey had like heaps high gearing they had 1 of them speed things the council put on the side of the road around the corner from mine got clocked at 89k also running av gas

Edited by overboost

I used to own a Polini racing pocket bike which i bought at an auction. Polini is the real stuff not the chinese stuff and man, this thing FLEW.

Rolling from 10km(id wheelie off the line/single gear), i would beat my mates 97 laser to 60km/h (topped out) by 2 lengths...haha...thats pretty fast for a little bike ey?

The reason a turbo kit wont work is because you need EFI, otherwise it just leans out like a bitch. UNLESS, you do what the guys on the nitro car scene do and use the boost pressure to increase fuel pressure, infact, that could actually work. Run a +ve pressure line from the turbo out to the fuel tank to increase the fuel pressure...hmmmm....!! Regardless you would need one SMALL SMALL assed turbo for a 50cc engine. Even a turbo off one of those 600cc cars would be too big. If you had the tools, manufacturing would be the way...

Nos will work no problems, but you will need to tune the thing into mega rich. This wont help the idle out but at least when you hit that button the a/f ratios will remain good...

The best idea would be

-Nos, used to spool the turbo

-Turbo increasing FP

-tuned rich to compensate for turbo and nos

Now that, i could see working.

Sounds like a fun little project really, but quite a lot of fabrication. Custom exhaust manifold, intake, carbby, etc.

BTW, the guy in sydney, i think they installed EFI.

This is the bike i used to have, http://www.dcminimoto.com/910desmo42.htm

I sure do know how to richen up a carb, spent ages tuning my s**t for changes in weather. I never said you cant turbo a carby car, i am talking about small capacity pocket bike engines.

Tuning a carb is quite difficult on its own, without forced induction. The biggest issue i see with tuning a small capacity carby turbo engine is the turbo lag. The bitch just wouldnt spool up fast enough before the mega rich mixture at high rpms (adjusted for full boost) will cause it to bog down and underperform.

This was discussed many times on the pocket bike forums (yes, laugh away)

There are just much smarter ways to get power then turboing a pocket bike.

What RC people did was s/c the engines. www.rbinnovations.com . Now thats a good idea because the car will be able to be tuned more consistantly. Also, as i said above, you can put some pressure back into the fuel tank to increase the fuel pressure.

meh, i dont care, i have a stagea now :)

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