FS1 forum

Hi guys !

Thought i would tell you you about my latest project. Electronic advancewd ignition on the old FS1

I all started after i got my 72 registred as motorcycle (normally they are restricted as a 30 KM/h moped :X ) well actually it started with me getting my motorcycle license early'er this year

I choose my 72 street with rotory valve to be my bike.. easyest MOT i've ever been to... he pressed the front brake, brake pedal and read the framenumber he didn't try it, didn't check lights, horn or anything

Anyway, tried a mate's 78 DX which was fitted with complete ignition / generator from the 80's Yamaha Passola scooter. More crisp ignition and much better light (25 watt VS 15watt) AND the battery is charged much better.

I fitted a passola stator, flywheel & CDI unit... Very easy... you just take a FS1 stator plate, put it in a lathe and remove 1 mm on the backsite, then measure the diameter of the center alignment on the passola stator an make the FS1 stator plate fit in the passola stator (see pictures) Passola stator is fitted so the pickup coil sits approx. 20 minutes past. Flywheel MUST be Passola type as it is 2 mm larger in internal diameter. If anyone want's to give it a go, i can give you some measurement to place the statorplate correct for 1,8 mm BTDC.

This was first step, and i got electronic ignition and better light... there is one minor issue though... due to internal pickup, it sparks both BTDC and BBDC.. that could make trouble if you want advance via a CDI unit that counts the RPM to determine when to advance.

It CAN be done, but you have to look for a Advance CDI made for 2 sparks per rotation (f. exs. the PGO Comet 50cc scooter)

Next step was to find a stator unit with external pickup coil and an even more powerful generator

I have a mate who's very much into The 90's Yamaha Jog 50 cc scooter (early type used called "artistic special" ) there are 3 different models which is quite different electrically.

He wanted to give me a complete stator with flywheel and CDI couldn't say no.... had to try it...

There is more work to make this unit fit in the FS1 engine, but not too much actually.

First thing is... The flywheel center conus / cam has the wrong size... BUT you can very easyally fit a FS1 center conus / cam in the jog flywheel instead. Flywheel is a little smaller but center hole s direct fit.

Next step was to make room for the stator in the engine casing... puuuhhhhh Hmmmmmmm....the pickup is large and annoying.

after some cutting,& grinding it fitted right in (se pictures) no changes has to be made to the engine case (important to me) the stator plate diameter is same diameter as FS stator.

There is one thing though... the flywheel has to be riveted to the center conus / cam. There is no excess room for nuts or rivets between the flywheel and the internal primary coil, so you have to use rivets that is countersunk in the conus and pressed on the outside of the flywheel.

I measured the BTDC through the plug hole with a slide caliper, fitted the flywheel without the key ind the crank shaft. that way i could use a timing gun to check the timing and meassure / calculate the correct possition of the cam VS flywheel. First attempt gave me 3,3 mm BTDC but it fired up and rev'ed up nicely with the standard CDI Unit

Next thing is that the Yamaha Jog stator is 12 volts, so you have to change battery, bulbs, horn, flasher relay & rectifyer (rectifyer is a complete different and much better type which uses both periodes of the AC current to charge the battery)

Next episode will tell you about my choice of programmable CDI Unit

great minds think alike, let's say..


looks véry familiar

Nice job

Today I got my programmable CDI unit from the czech republic.

http://www.ignitech.cz/english/dccdip/dccdip.htm

here you can see the software for the unit.

Can't wait till tomorrow.... I hate this rain today

looks very interesting!!

what is the internal diameter from a Passola flywheel?

mpro09 schreef:looks very interesting!!

what is the internal diameter from a Passola flywheel?

Approx 84 mm VS 82 on FS1... Wait.... maybe the later 2RU is 84 mm diameter too... but they have a wrong center conus / cam (the high point for the breaker will touch the end of the pickup coil)

Today it fired up I've had some problems getting a spark..... finally found out it was just a setting in the software (polarity of crank position sensor was set to "positive" but should be "negative" ) that's why i didn't get a spark "out of the box"

Please ignore really bad running... cylinder top gasket is VERY leaky so it barely can start with kickstarter :$ I'm waiting for my freshly bored 45 mm cylinder.

Here's a video so you can se it run..

Is this with the programmable CDI unit?

marco schreef:Is this with the programmable CDI unit?

I think it is, because if you see the stripe going right it advances with the ignition

marco schreef:Is this with the programmable CDI unit?

Yes it is... no adjustments done though... I fitted the freshly bored cylinder yesterday and i'm working on breaking it in... did 60 km yesterday with the RPM limitter set to 7000 RPM. Soon i will try full throttle and try some adjustments on the advance

Great to see that it works perfect.

But make's me feel stupid....!!! Because i dont understand a thing about how this works