Excessive kick start - kickback.

Morning All,

Having finished fitting my project with ECCEL Coils and DYNA-S electron ignition and new carb internals, I decided to kick her over (no sissy button)......I tell you I haven't experienced kick back that bad since my old Ducati Bevel. By kick back I mean, the kicker returns violently.

Now as it's an inline four not a V-Twin, I am at a loss as to why it should exhibit this level of kick back.

Bike Spec worth knowing: I'v converted a CB750F1 to 836cc, high performance coils and Dyna ignition. Standard carbs, jetted +2 main / standard pilot. Compression on fresh build = 165psi across all pots.

My suspicion is that the ignition is too far advanced, which leads me nicely onto the next question. The Dyna-S spec sheet says to static time No.1+4 /2+3 at the advance marks (two lines to right of T mark). I personally would have set the static timing at the F mark, as with points.

I static time using the traditional idiot light hooked up to battery positive and the corresponding 1+4 or 2+3 leads from the Dyna pick-ups.

Help, advise and more brain cells very much appreciated.

MCR.

Sounds to me like pre-ignition as well, but I am carp when it comes to things like timing!

Have you had a look at the Honda SOHC forum? Very knoweldgeable people when it comes to the CBs, go to http://www.sohc.co.uk and see what they have to say.

.

Thanks for your replys,

I'm leaning definately towards over advanced ignition, so I will (tomorrow) set it to the F-mark.
Yes Miffa the stator / pick-up wires are correctly routed, worth asking though.

When fired up she runs strong and sweet, just a git in its current setting to get going.

Ref; the 160psi per pot, my mate who runs three classic endurance Z1's has 185psi per pot, running high compression pistons and very much non standard internals.

Will let you know how I get on.

Cheers.

.

Ok, retarded the ignition to F mark then backed it to T mark to enrich it a tad. Fired up third kick (after clearing excess fuel build up) and she runs a treat.

Regarding the kick back, gone now, just the compression to overcome at TDC and away she goes.

Thanks Paul & Miffa for your help, it was pre-ignition after all.
I will video and post stats when I have her Dyno tested in a couple of weeks, I look forward to the results