injecting a *small* engine

[Paul Rosser]

I realize that it is possible but the time and expense would probably be=
 rather high. How about NOS. I have a article on a guy who NOS his little=
 scooter. eg the ones that are like a skateboard with handlebar's. It has a=
 35 cc motor on it going through a single speed drive train. The kit is of=
 the shelf for a 35cc engine so you should not have any prob's. Now that=
 should have a big power boost. I have one question. Ho come you are going=
 to a distributless ignition system. I presume that the bike is single=
 cylinder so why not go to a plain electronic ignition module that uses only=
 the orig coil. These little modules can be brought from most lawnmower=
 shops for around $25 dollars. Are you hoping to incorporate ignition=
 advance because that would be a good (but new) idea on small engines.). Now=
 for some bad news. The turbo is out, Last I heard is that turbo's are only=
 come small enough for down to 500cc engine's. The other problem is that for=
 a single cylinder engine you have to use a big plenums chamber before the=
 turbo to average out the exhaust pulses.


Anyway after all that you bike does sound very interesting and the potential=
 is there as well. I did not realize the extent of you original mod's. Keep=
 me up to date with the EFI progress. I am also interested with the=
 performance increase of the distributless ignition system. I am now tempted=
 to get the old mini bike out for another rap soon.( has been keeping the=
 dust of the floor for about a year). The bike is not bad a 100Kmh but=
 security is not high. Brakes consist of a metal flap on the back tyre and=
 the front wheel tends to shimmy a lot. It does have good balance and=
 corner's not to bad considering the square tread. I do occasionally wear a=
 motor cycle helmet and long trouser's but as most of the time it is used=
 off road the damage is slightly less. I am currently looking at building on=
 of these small scooters(as mentioned above) and already have a 50cc=
 chainsaw motor standing by. I plan to gear it for around 50-60kph.


Anyhow shall go.

Have a good day

Paul





At 11:20 AM 2/27/97 +0000, you wrote:

>Hi Paul,

>thanks for your reply.

>I have a few remarks tough:

>

>>  Since it is on such=3D

>>  a small scale you will having trouble getting sensors and injectors to=
 run=3D

>>  at such low increments.

>

>As I said, it has been done by the Tippa fuel economy team. So there=20

>must be a way. Nothing personal, but I want to hear all there is=20

>before saying it's a no go on EFI.

>

>>  since it is OHC engine I presume its a 4 stroke. Have you tried to get=
 it=3D

>>  cam'ed. Do things like port it and increase the compression ratio.=
 Crank=3D

>>  the timing forward and use a proper race carb. These mods will yield=
 more=3D

>>  power than EFI will give you.

>

>The head has been flowed/tuned (whatever you call it) I've fitted an=20

>advancing flywheel and put the timing forward. A Keihin 19mm takes=20

>care of the fuel delivery. The standard airbox is replaced for a=20

>sports filter. An oilcooler from a citroen 2CV is fitted. 70 cc can be=20

>used for 4- strokes in the moped races here to be a bit more=20

>competitive to 50cc 2-strokes.

>I'm currently adjusting the piston for higher compression and will=20

>build a lighter clutch assembly soon.

>The speed was over 100 km/h. I'm going to get a race cam from Japan=20

>and some other stuff so it's going to get faster.=20

>I'm planning to build the Digital distributorless ignition system if=20

>any of you can tell me it's good. I think it is. So maybe EFI is just=20

>a wild guess, but if I can do it ,cheap, then I will, just for the=20

>challenge. Was thinking of turbocharging too, but that would be a=20

>hell of a challenge :-)

>Looked at your page. A 2-stroke minibike is still a different story.=20

>After seeing it, I would not feel so safe driving it around 100 km/h=20

>Adjusting a whole bike takes a lot longer to do properly (brakes,=20

>etc..), which you already know, ofcourse. Your mini-bike is just for=20

>fun. Time, work, some money and ofcourse some help from other=20

>enthusiasts can help build a race bike. That's why I have contact=20

>with fellow 4-stroke moped racers in The Netherlands and the United=20

>Kingdom and plan to organize a 4-stroke moped racing association.

>And why I called upon DIY-EFI.

>

>August.

>

>

>

>=20

>

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__________________________________________________________

Paul Rosser

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</color>587 Frankley Rd	             	Ph  64 6 7539372

New Plymouth				Fax 64 3 7539372

New Zealand

<color><param>0000,0000,ffff</param>Web Wheels =3D=3D>=20
<bold><underline>http://www.geocities.com/motorcity/3812

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