Anyone have access to an electronics guru?

[SteveNZ]

I'm trying to work out how to make a poor-mans Nikko box instead of the TRE mod for the K3. Basically it would require someone who can program a simple logic circuit which will switch depending on what gear and alter resistance, along the lines of:

1st gear = normal
2nd gear = same resistance as 6th
3rd gear = As above
4th - 6th gear = normal

In code form ya basically got:

(IN = Input resistance, OUT=output resistance, numeric values are KOhms)

If "IN < 0.8" OR " IN > 2" then OUT=IN; else OUT=15.

Upshot, 2nd or 3rd gear appears as 6th gear, all the others appear as they should.

Basically this just gets around the troubles with idle and cold-starting with the normal TRE mod. Making the circuit would be dead simple for someone with the right equipment (eeprom programmer and suitable chips etc), unfortunately, I can't lay my hands on any except buying some for about the same price as a Nikko G-Pack anyway.

This won't get rid of the rev-limiter, but I'm quite happy to leave it there anyway.

Anyone got any clues, or shall I just stick with the resistor? :)

[TSM]

Why dont you just buy the TRE mod bits on ebay? They are very cheep anyway.

[Cloggsy]

Anyone got any clues, or shall I just stick with the resistor? :)

I never had any problems with cold starts etc... Just stick with the resistor :!:

[SteveNZ]

I can do the normal TRE mod in about 5 minutes flat using a couple of bits of wire, a pair of pliers, some electrical tape and a 1Watt, 15KOhm resistor. I'm just trying to avoid what little, albeit fairly meaningless, issues that result in neutral during coldstarts.

Doing it properly with a switch takes about another 10 minutes as I've gotta fire up the soldering iron...

[dangerous bri]

hello mate

could you supply me some more info

in general terms on what a nikko pack

or the TRE mode actually does ?

as much info as possible would be helpfull

i've got a motorola HC05 eprom programmer

i've never had the time to sit down and use it.

You could probably get away with using PROMs

once you have everything worked out

this would save swapping chips once you have

an all round setting that you can live with

all the best

dangerous bri.

[SteveNZ]

All the mod does is trick the bikes computer into thinking it's in 6th gear all the time. Otherwise, in 2nd and 3rd gear (or was it 3rd and 4th?) it slows the ignition timing slightly in the midrange, allegedly to pass some sort of testing. If it thinks it's in 6th gear all the time by putting a 15K resistor inline and bypassing the gear position sensor which would otherwise report a variety of values depending on what gear the bike is in, the problem is eliminated and you get a very slight improvement in full-open acceleration from midrange in 2nd and 3rd gear.

However, one side effect is that it also thinks it's in 6th gear even when it's in neutral. I had some issues starting the bike when it was very cold as a result of this. It seems like a safer prospect to me to make a proper circuit that makes the bike think it's in a higher gear than it is only when needed, rather than all the time. If the timing isn't retarded in 4th, then might as well get the chip to set the resistance to that of 4th gear when in 2nd and 3rd and otherwise leave everything alone. Change as little as possible while still getting all the benefits.

As near as I can figure, the Nikko G-Pack does pretty much exactly this, except it also removes the rev-limiter (not sure how), and it comes with proper Suzuki connector so the entire thing can be installed by unplugging 1 connector and plugging either end of the plugs into the G-Pack. Paying something like US$200 for the privelege is a bit much though for what I perceive to be a very simple circuit. And while the plugs are nice, they're hardly a necessity.