Dynojet power commander Q's

**Timber020** · 6th February 2006, 20:49

Got a great little fireblade, has a power commander under the seat which has a timing light, and two adjustments, one for the rev limiter and one for retarding the ignition.
QUESTION-When why and how would I need to adjust the ignition? I have looked on MANY websites but none seem to explain it to me in a way that gives me any understanding.

Thanks

**cowpoos** · 6th February 2006, 22:13

leave it alone to do its thing.....its not a playstation...

**750Y** · 6th February 2006, 22:34

you might wanna change them when you've changed cams or cam timing which have the potential to cause the standard timed spark to occur at a different point in the cycle of the valves opening/closing or leaving them open/closed for a different period of time per revolution of the engine, eg the spark ignites the fuel & it takes a certain time for that fuel to burn to it's most potent point after which it starts fizzling out(kinda like a 'flash point'). well if your valve opens at a certain point in relation to that flash point that's cool, but if you change your cams the valve may now open later or earlier in relation to that 'flash point' which means that now you are out of sync so you might dial back or forward the ignition(spark) to account for that change. (Of course this is assuming that the current ignition timing is optimal.) There will be a need for different ignition timing at different revs because the fuel takes a set time to ignite to the 'flash point' but as revs climb, less time is available for the fuel to reach it's flash point & for the valves to open/close & the piston to move up/down. so sometimes at higher revs you gotta get the spark started earlier so the fuel has time to hit the flash point right when the valves open/close & the pistion goes 'take that!'. That is why the igintion timing on a bike is a 'map' which changes at varying revs & that is why the tool allows for timing adjustments at intervals of 500 revs(or smaller with some tools). there's heaps of maths & stuff to calculating it & things such as chamber size/shape get added in too which can be effected by head gasket thickness, skimming head, different pistons.porting etc etc. then of course there's different fuels which have a different burn rate & flash point. bla bla bla
some stock bikes were well known for benefitting from a advancing/retarding of the ignition & for some of those you could buy aftermarket ignition timing rotors which lifted the whole ignition map by say2 or 4 or 6 degrees(max safe 'race' style at the time cos they got warm). many ahem backyard fiddlers even slotted out their own & err measured the degrees with a tech drawing compass & a calculator then notched the marks on with a screwdriver but i wouldn't know anyone that bodgie round here.
i hope that sort of helps, i don't know about you but i've totally confused myself now, lol. 8-) someone who actually knows what they're talking about will no doubt be able to rubbish all of that

**pritch** · 7th February 2006, 07:37

Originally Posted by cowpoos

leave it alone to do its thing.....its not a playstation...

I'll second that. Leave any adjustments to the guy who operates the dyno.

**mjvduc** · 7th February 2006, 19:18

I think most of the important stuff is said

you can download a map (for free) from www.powercommander.com and use it on your bike, this isn't the perfect solution but maybe you bike will gain some advantage and runs much better (especially if you have aftermarket cans, filters etc…). To do a proper set up you need either a dyno run, something like that www.widebandcommander.com

or do your own test rig (oxygen sensor(s), indicator etc….).

good luck

mjv

**Timber020** · 7th February 2006, 19:39

Thanks guys. especially 750y for the well thought out explanation. I wont mess with it!

**Idrumm** · 7th February 2006, 19:57

If you want to get serious give these guys a bell they are one of four in NZ, authorised to tune dynojet power commanders

Pro Cycles, New Zealand
Power Commander Tuning Centers can optimize the fuel and ignition mapping for your motorcycle. They can also develop custom maps for special applications. All "Dynojet Approved Power Commander Tuning Centers" have the latest "state-of-the-art" Dynamometers and testing equipment. This includes the new Dynojet Model 250 Load-Control Dynamometer and the Dynojet realtime Air/Fuel Ratio module. In addition, these shops have successfully completed the Power Commander technician training course at Dynojet Research.

Address:
27 Carnegie Rd
Onekawa, Napier

Phone:
06 8420915

**Lou Girardin** · 8th February 2006, 07:30

Be very careful with map downloads. Most of them are overseas developed and not suitable for NZ.
Spend the bucks and get it mapped on a dyno.

**sAsLEX** · 8th February 2006, 08:00

Originally Posted by Lou Girardin

Most of them are overseas developed and not suitable for NZ.

Fuel?? cant think of much else that would be too diff

**pritch** · 8th February 2006, 10:58

Originally Posted by sAsLEX

Fuel?? cant think of much else that would be too diff

Try engine specifications fer instance? Models made for different markets sometimes develop different horsepower,
eg some have catalytic converters, some don't.

Other than that NZ spec Hondas are "full power", nobody I have asked has been able to give me a definitive answer as to what the variations are, and that includes the Blue Wing service rep.

So I had the standard map checked and it was "lean at the top end" so I had a custom map done (AMPS).