G'day from Queensland Australia

[duivendyk]

Fear not too much,that Kaw 750Z is intimidating allright, but quite well behaved compared to that treacherous rather innocent looking 2 stroke job.Just looking at its engine you would never have believed that it was good for 180km/hr plus.

 

[Sachs-rider]

Drilling holes in your Sachs/Rotary CDI - Restrictions

Drilling holes in your CDI module is a very bad idea, forget it, your going to destory it!

If you want remove the speed/power restriction on you SACHS 301/A or Rotary 30 cc engine, Either biuld your own replacement CDI http://roadrunner.woelmuis.nl/CDI.htm or VERY CAREFULLY modifiy your CDI module.

Inside the RED MOTOPLAT SACH CDI resin-filled CDI there are two trim-pots (blue and white) your need to cearfully grind out the plastic box and resin inside to get to the trim pot (Marked 2K or 2K5) If you get to it and can turn the trim pot fully anti-clockwise, your engine will rev up to full speed.

I ride around on my Saxontte/Sparamet at around 28 - 30 km/hr with either the road-runner home-made CDI or the modified MOTORPLAT unit.

Let me know If you wnat PICS of the Modification, I dont recomment doing the mod untill you biuld yourself a road-runner home-brew one.

Patrick

 

[Irish John]

I attach a picture of the CDI Modification. Be aware that my (1992) SACHS is a model 301A with a BLUE CDI unit. Evidently the blue CDI is the most common but there are RED and BLACK CDI units.

For heavens sake do not go drilling holes into your unit until you have comprehensively researched the subject! I went so far as to JOIN the Dutch Saxonette forum (I understand German but struggle with Dutch) and having babelfish translate the posts until I understood what they were on about.

What I found was, with few exceptions, all the guys, who after reading the quite amazing increase in performance obtained by drilling the CDI came back enthusiastically relating their experiences. I also learned there was a Dutch guy, name Jan jhcvaal@kabelfoon.nl who is the World expert on these and will supply a modified CDI for 45 Euros plus postage.

From what I can tell the restriction simply limits the motors RPM. Take it away with the drill and the little motor behaves as its designers intended. There is a whole WORLD out there of which I was unaware! All these guys who love mucking about with tiny motorbike engines, I love it! According to Jan a few other mods and you really get a tune out of the Sachs. He reckons the best speed so far obtained is 58Kph! I hasten to add that mine runs to about 30 Kph or maybe a little more. I don't have a speedo and the roads around here are typically Australian rough bitumen. At anything over about 23 or so (a guess) there is considerable vibration through the handlebar of the Bike which is tiresome. I am thus content to tootle along at the lower speed and watch the scenery pass and since the modification I seldom have to pedal unless the hill is quite steep.

I cannot say what effect (if any) it may have on the Rotary made Motor. I understand these are exact ASIAN built copies of the Sachs 301A motor. If so they should behave similarly. Beyond saying beware, that's all I can do.

All the best to you.

I've serviced a few of these and they are mostly really good motors. I have one at present that I can't get a spark out of. I had it running today but it faded when the throttle was opened so I cleaned the carby. Nw I can't get it to start. Pulled out the Bosch plug and laid it on the cylinder to see if there was a spark when I pulled the starter rope but no spark. I wonder what the problem is cos the CDI is made to be indestructible and trouble free. Everything else seems OK. I'm baffled. These are lovely made motors but very low on power although nice on the flat. Over a long distance the slow speed becomes a bit boring.