Posts
11
Joined
8/6/2023
Location
New Stanton , PA
US
Hi everyone. I can prime the intake with a spray bottle, and get the bike started, but you have to keep the bike running. It won’t idle. When it quits, you have to prime it again. It’s got a new fuel pump, new injector, new intake flange and clamps. It’s got pretty much new everything. New map sensor, intake air temp sensor, coolant sensor. It does have a Yoshimura slip on. Is it possible that the ECU needs remapped richer?
thanks in advance
Check your valve clearance. Most likely intake valves are tight.
I did. The valves are spot on. I’ve even set them on the high side of the specs. Also just put a new camshaft in it because the gear had spun just enough to throw the valve timing off. I’ve really done everything I can think of. I’ve even sprayed around the airbox and intake boot with carb cleaner to check for intake leaks, and no change. If I spray a little gas on the air filter while it’s running, it will smooth out and improve, but without the extra fuel, it quits running.
The condenser is probably bad. That would explain why it only starts when manually primed.
You could also have a bad ECU. Look at the wiring diagram for the bike. There are circuits for the fuel pump and injector that pass through the ECU.
Here’s a list of what was replaced or replaced from a running bike:
wiring harness, kill switch assy, injector, fuel pump, map sensor, coolant temp sensor, throttle position sensor (not replaced, but checked, set to spec), stator, condenser, fast idle adjuster, ECU, intake air temp sensor, spark plug, coil, flywheel and key, intake flange. (Kick start pedal because I’ve worn one out trying to start this bike…lol!) I’m sure I’m leaving something out. Also performed leakdown test, and compression test, all good. New camshaft and timing chain.
So I did get a new camshaft because I read on here from a few of you knowledgeable guys that the cam gear spins on the camshaft. That was the case with this bike too! Mine was spun, and I finally got it running, but only by shooting gas into the throttle body. It does have a Yoshimura complete system on it and I’m wondering if the ECU was never reprogrammed richer for the exhaust. So I ordered a Big Gun TFI tuner to richen up the mixture. I’m wondering from you guys that have experience with tuners if you think it will solve my lean problem?
Thank you to all you guys for helping me so far.
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The exhaust does not change the mapping requirements significantly. Definitely not to the point that it would not start but would start being primed.
Swap the entire wire harness over from the other bike. Heck, it's the only thing left!
That’s why I’m stumped, it has a brand new Honda harness on it, I’ve replaced that too.
I have a Big Gun TFI Power Box on order. I’ll definitely post my results, I don’t know what else to do, other than sending one of my ECU’s to Tokyo Mods.
Sounds like your problem is w fuel delivery Know you replaced injector an pump but it seems like its not maintaining pressure
Hello! I’m posting an update, incase this thread helps anyone. So I found that when I finally got the engine started it had rough idle and when you gave it throttle, the idle would hang like it had an intake leak, or the butterfly wasn’t going entirely closed. It was also fouling plugs and smelled like gas after the engine was shut off, and it was getting fuel into the crankcase oil, and was very hard to start when hot. Well, it ended up being the fuel injector. I had previously replaced it, but with one from Amazon. Don’t go the cheap route! I then ordered one from Honda…well, it runs perfectly now.
Thank you to all of you who helped me with this!
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