My race bike isn't starting. It will occasionally fire and run for a second or two then stall out. I have tried swapping ecu, idle air control, intake pressure sensor. I took the throttle body out verified the injector is spraying. Also check and changed the spark plug appears to have good spark. Took a test light to the injector to make sure it's getting voltage and trigger from ecu. The crank position sensor tests out ok as well. Also doubled and triple checked timing and valve clearance. Tried to do a leak down but the harbor freight setup I got it junk. With the decompression I am seeing roughly 75 psi of compression. Readjusted tps to .68.
Mods are 13.1 weisco bnr piston, hot cams builder series intake cam, vortex, ported head, fci. Quad has a total of 9.6 hours and runs on sunoco 104 oxy fuel. Any suggestions would be great missed out on the steele creek national this weekend.
Hi,
It seems you've already check a lot of things.
1)Try with a battery booster, it seems vortex don't like low battery voltage:
You can Check your ECU voltage during cranking, and clean the fuse/relay connections.(under your seat).
2)Check your lean angle sensor.
3)It's possible your crank bearings are faulty: i've seen a lot of engine not able to idle correctly when it's not completly seized...
Charge your battery and try again,
We had the same problem: engine is cranking but the Vortex don't ignite. It seems the Vortex is less tolerant to low batt than the OEM ECU.
i just rebuilt my motor for bottom end crank shaft bearing...
Key symptoms:
-out of time
-runs at idle for little then dies.
-metal shavings in oil.
Could be an ecu issue, but if u tried stock i dunno... go back to basics... fuel, air....
your compression seems on point. do you have a kill switch? and does it ground?
Try putting in the stock exhaust cam. Those hot cams have a longer decompression pin bleeding off to much compression. The Vortex seems to be particularly sensitive to that. I had to take my cam apart & grind down the decomp pin little by little until it reached about 90 PSI of starting compression.
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