Project X

[teazer]

And a richer mixture will stand more advance - not because it needs it, but because the excess fuel is keeping things cooler, so don't dial in lots of advance with a rich mixture and then lean it out and burn the house down. And the hotter the combustion chamber is, the faster the burn, so a lean mixture and lots of compression and advance and pistons start to evaporate.

[madforitkev]

OK

Will start at 30 degrees on tickover reducing to 19 at about 6k for now then drop that again to 10k.

1000 - 30
2000 - 28
3000 - 26
4000 - 24
4500 - 22
5000 - 21
5500 - 20
6000 - 19
7000 - 17
8000 - 15
9000 - 13
10000 - 10

Is 10 too low at the top end? I was thinking around a 14/15 degree drop from 4k as that is close to other curves I have seen.

In the end its just a start point but does this look reasonable?

[teazer]

The reason to go so retarded after peak is to a. allow some overrev and b. to cause it to stop making power so it's a soft rev limiter. That motor at 9000 plus will eventually throw a leg out of bed. Peak at say 8,000, red line at say 8,500 but better to keep it at less than that.

The load on a big end is proportional to the square of the revs, so small increases in peak revs have significant effect on crank and rod life.

But you still have to test those numbers on the dyno and see if it works. They are just a place to start. I don't recall what heads are on that motor, but if it's a stock shape, the igntion advance range may be less.

[madforitkev]

Rich

I was assuming max out at 8500, so all good.

I did the removable squish head design if you remember (somewhere back in the posts).

Anyways, 36-1 crank wheel and sensor on the way. Wifey has promised me a Speeduino for Xmas which all ties in nicely after the dyno runs.

Next read is to understand why the KTM crank pressure system seems a bit flawed and why they have this new ambient pressure sensor that seems to have solved everything.....of course it may be irrelevant for the old girl but.....

https://transmoto.com.au/explainer-the- ... re-sensor/

While I a running basic revs vs TPS as a start for injection, it would be nice to work in engine load.......

[teazer]

I'd speculate that the HP level; of those new bikes is much higher than even a TR750 and as such they will be more sensitive to changes in air pressure. That applies to altitude of course but also to changes in relative air density which would require changes to fueling and perhaps to ignition advance too.

You can grab an air density sensor for many bikes and connect it to your ECU. Higher RAD needs more fuel and slightly less advance.

You could also add in a knock sensor and signal conditioner to tell the ECU to back off advance. I just bought one from http://www.ms2tuning.com/products.html

They only have single and dual channel but that should be sufficient. Fit two knock sensors on the cylinder head and hook up the ECU lead, or just run an external LED and watch the flash frequency.

[madforitkev]

Found this.

Looks kinda interesting... will do some more digging.

https://www.youtube.com/watch?v=slh7DsR7S3U

[madforitkev]

Bit of a a return to the starter issue.

Initially I had hoped to use a GT185 combined starter/generator to double up on features and make room for a RH side ignition system by loosing the alternator.

I got my torque maths a bit wrong and there wasn't quite enough power to turn the motor properly.

So back to plan B. Refit a normal starter motor and starter clutch. The challenge being I still have to mount my hydraulic clutch slave.

The upside is this actually helps the fuel injection project.

My starter clutch/hydraulic slave side now has space to fit a crank position trigger wheel and sensor on my clutch slave plate and the trigger wheel will bolt right on the slave clutch (trigger wheel not shown in this pic).

The EFI work also means I can now loose the RH side ignition pickups and either leave the small lighting alternator in place or if I need more amps (which i probably will with all the fuel pump and injectors etc.), I can refit a normal alternator again...

[Alan H]

I did a hydraulic clutch on the 550 here - viewtopic.php?f=16&t=5620&hilit=Earwig&start=310 - towards the bottom of the page which works fine, but yours has a neater unit fitted (doubtless more expensive as mine was less than a tenner!!)

[madforitkev]

Nice,

I wanted to go through gearbox and the dry clutch made an outside slave tricky.....but between you and me mine was a old KTM dirt bike slave I had knocking around in a box, so cheap as chips

[Alan H]

Hahaa! Smart move!!