Ignition pick up slotted

[boo86]

Hi guys. Finished this off last night. See pics. can I just TRIPLE check I've got the off set the same way as the rest of you who ADVANCED the timing. I'm 101% sure it's correct but with your feedback I'll be 102% sure. Which is better obviously !!

Ive ofset it counter clockwise looking into the cover from inside the bike. So the pick up meets the rotating trigger slightly earlier on it's cycle.
Cheers,

[SpeedDvl]

i am interested in this mod but never heard of it before. i can't find any info on it. how much advancement did u get? how is the bike running so far?

[boo86]

search 'cheap ignition advancer wanted' on here. I understand about 3-4 degrees of adavnce. If you take the genny cover off and have a look how it all works it makes sense. The trigger passes the pick up slightly earlier on it's rotation as you move it counter clockwise. So it advances the ignition slighty. It cost me £3 to do. (Liquid gasket !)

[embee]

I measured 2deg on mine. You might stretch that a fraction but you won't get 4 {unless you seriously carve up the gen cover mounting points}.

The most noticeable effect is pulling away from standstill, i.e. low/mid revs, where it felt much more responsive. This was confirmed by swapping between 2 identical bikes, one with and one without the mod.

This makes sense since it is at low revs where the ignition calibration is going to be most retarded for low octane fuel {91 RON is the calibration} so the effect of a couple of degrees will have the biggest effect. At higher revs the std calibration will be nearer to optimum anyway so ''ignition response'' will be less.

[boo86]

embee did yours look like mine ? I did think of filing away the mounting point and only mounting it on 1 side. I may do this at a later date. I'll see how she runs first. Was it you who did this mod AND runs a offset woodruff key ?

[embee]

It looked just like yours.

No, I only have the slotted pick-up at 2deg. I wouldn't personally want to go more than a couple of degrees, the offset woodruff key at 4deg absolute tops without knowing something more about the sensitivities and peak cylinder pressures etc.

I am aware of the typically conservative Japanese calibration philosophy but I don't know how near to optimum the std timing is at higher speeds, you really need to see perhaps 3 reliably repeatable dyno runs at std, +2, and +4 and do direct comparisons throughout the speed range to decide what is viable. I'm sure the likes of JHS et al have done exactly this, but I'd want to see it for myself.

Peak pressures increase quite dramatically with ignition advance, as do plug temps. Peak pressures are what load bearings, gudgeon pin bosses, ring lands, head gaskets etc.

I still use std plug grades because I don't tend to use high revs a lot, but if going to 4deg I'd definitely go one grade colder. 4deg ignition on a std plug will give something of the order of between 50 and 100degC extra plug temp {probably somehwere in the middle}, which is bordering on risky in my book.

[SpeedDvl]

i have the newer bike - 08. don't know if it is the same? i know for newer cars, u can't do this. only in the older cars can u rotate the distributor.