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hanwool
03-18-2011, 07:09 AM
Now.. we are trying to start aprillia engine svx550 with using ECU for one month.

Sometimes it works but it dosen't work about 5 hour later.

I think it is very unstable.

I don't know where can i figure out problem.

Injector placed close to intake port and i think injection timming dosen't have problem.


What problem can be exist?

please give us any advice.

thanks for reading

Canuck Racing
03-18-2011, 03:45 PM
1. That's not very long from what I hear at competitions, though I do recommend to all teams that you try and use the starter motor. An ECU will not give the required torque on the starter gear unless you machine it.

2. You should be able to fit the endurance race within this window so don't worry too much.

3. Bolt the engine down to something. You sure don't want it landing on your toes if it falls over.

4. Check spark timing.

5. Buy yourself a CBR600.

6. On a more serious note, the simplest way to start in my book would to be to shut down, wait your 5 hours, then try and "reset" as many things as possible. Make sure the water/oil temp is ambient, pull the spark plugs and clear out the cylinders, make sure the battery is charged, the ECU is re-booted, and probably even make sure that the starter motor temp is near ambient. You need to re-create the conditions from 5 hours earlier as closely as possible. If you can replicate them, it should start again. If it doesn't start, it's just the engine gods welcoming you to the experience of Formula SAE.

Sam. B.
03-19-2011, 09:04 AM
What kind of timing do you have at starting rpm?
Make a compression test and tell me the results.

You can also make some research of apriliaforum . com

hanwool
03-19-2011, 11:10 AM
we use 350rpm on starting.
Compression ratio is apporoximatly 12.
Actually aprilia engine has variable exaust cam.
How can you control that?
Starting engine is really hard.

Damon Pipenberg
03-19-2011, 04:47 PM
Are you using the stock Aprilia ECU, or an aftermarket unit? If aftermarket, what brand?

This engine should start quite easily with the stock ECU and intake manifold. If you are having problems with the stock unit, I would double check your wiring harness, battery voltage, fuel pressure, etc, all of the standard things.

If using an aftermarket ECU, try to find a way to verify the timing on both cylinders. This is difficult with this engine, but it is possible. I think that many of the starting issues that teams have with this engine are related to incorrect timing. It can be tricky to get the crankshaft and camshaft sensors configured properly to synchronize the ECU.

Brokenrider
03-20-2011, 02:18 AM
Yes. As I know, Hanwool uses halteck ECU which has difficult setting trigger. According to my last expierence with haltech and 600RR, It is quite difficult to find the collect TDC Timing. At that time, I fried themhttp://fsae.com/groupee_common/emoticons/icon_smile.gif))

Sam. B.
03-20-2011, 11:00 AM
hanwool,

You did'nt answer to my questions.
What is your ignition timing for the start? -10°, -5°, 0°, 5°, 10° ???

What is the compression in each cylinder when you try to start the engine? 120 psi, 100 psi, 80 psi, 60 psi???

Do-it-Guy
03-21-2011, 11:52 AM
@ hanwool,

do you have any possibilty to give the engine a jump start (=not trying to use the onboard starter)? This would quite easily determine wether you have a starter or an combustion problem...

During the time, the engine runs by "mystical" reasons: Are you sure the engine is running correctly on both of its cylinders? 77° offset can be tricky with an aftermarket ECU

Wesley
03-21-2011, 12:07 PM
The "variable exhaust cam" is actually a cylinder decompressor that bleeds off some cylinder pressure to lighten the load on the starter motor.

Aprilias are REALLY picky about timing. Because they're an odd fire engine (77 deg v-twin) and also because they're only 2 cylinders, if you get your timing just a little bit off you'll nail your cylinder with combustion when it's on its way up and you'll have at worst 643 degrees of crank rotation before you get another firing event.

Make sure your timing signal is accurate.

Brokenrider
03-21-2011, 04:23 PM
They have found a critical problem causing miss fire. TDC of rear cylinder was not collecthttp://fsae.com/groupee_common/emoticons/icon_frown.gif futher more, haltech has maximum cylindet trim 40deg. Narrow setting range of haltech makes them crazy http://fsae.com/groupee_common/emoticons/icon_frown.gif

Eryk Sokolowski
03-29-2011, 02:56 PM
Hi what is your crank reference angle set to?

We had it set to 111'deg, and we had no luck with it, then we set it to 249'deg and it started working....

We also found that running a CAM sensor and running it with 720 sync rather than 360 like it's on the bike helped alot...

Currently our engine is very unstable, fluctuates almost 2200~3200 when idling...