Cranks, but hard starting?
Thread Starter
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Cruiser
Joined: Feb 2019
Posts: 106
Likes: 29
From: SC
Here's the update guys. I pulled the tank and pulled the hose. I replaced with the submersible fuel line. I did not see a hole in old line, but bike is starting perfect now and has great power on top end. Plus the bottom end stumble is gone.
Thanks again, for the help!
Thanks again, for the help!
Thread Starter
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Cruiser
Joined: Feb 2019
Posts: 106
Likes: 29
From: SC
well, spoke to soon. Started fine all day, now back to the extended cranking.
Just read another thread from a guy with same exact problem. He said they found out that the comp eliminator with the 551 cams was the problem. That is same setup I have. Something about it spinning engine to fast and messing with the spark output.
Just read another thread from a guy with same exact problem. He said they found out that the comp eliminator with the 551 cams was the problem. That is same setup I have. Something about it spinning engine to fast and messing with the spark output.
Seasoned HDF Member
Joined: Aug 2008
Posts: 5,071
Likes: 1,006
never say never, but, the signal is taken off the reluctor built into the flywheel so cranking speed is not relevant. you eliminated the cps so, use an inline spark tester to see if you have a consistent output. you can also use a noid to test injector signal. also, test cranking voltage drop on the battery. then there is intermittent connections, a sign that when you fiddled around with the machine, it ran fine for a day.
Thread Starter
|
Cruiser
Joined: Feb 2019
Posts: 106
Likes: 29
From: SC
never say never, but, the signal is taken off the reluctor built into the flywheel so cranking speed is not relevant. you eliminated the cps so, use an inline spark tester to see if you have a consistent output. you can also use a noid to test injector signal. also, test cranking voltage drop on the battery. then there is intermittent connections, a sign that when you fiddled around with the machine, it ran fine for a day.
Now I do think it had a hole in fuel line too, since my topend got more power since I changed line.
Trying to see if someone has a rotor laying around, so I can put compensator back in. Since it was the rotor cage that broke, not the compensator itself.
Seasoned HDF Member
Joined: Dec 2005
Posts: 19,921
Likes: 8,027
From: poway
I've not messed with the 551 cam or it's automatic compression releases but do know for sure that the Delphi system needs to sense a slowing of the crank when coming up on compression on the rear cylinder or no spark will occur. A stock 08 really don't have much compression. Adding auto releases combined with the solid comp might be screwing up with the crank velocity sensing. Your best bet IMO is to put the old comp back in and see if the bike starts better. If it does, install an SE / late model comp You may want to check the condition of your battery and connections also. If battery voltage drops too much, the ECU may not put out spark / fuel. Spinning the motor faster might help with the sensing of the slowing. Check voltage while cranking, should be over 9.5 volts.
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Thread Starter
|
Cruiser
Joined: Feb 2019
Posts: 106
Likes: 29
From: SC
I've not messed with the 551 cam or it's automatic compression releases but do know for sure that the Delphi system needs to sense a slowing of the crank when coming up on compression on the rear cylinder or no spark will occur. A stock 08 really don't have much compression. Adding auto releases combined with the solid comp might be screwing up with the crank velocity sensing. Your best bet IMO is to put the old comp back in and see if the bike starts better. If it does, install an SE / late model comp You may want to check the condition of your battery and connections also. If battery voltage drops too much, the ECU may not put out spark / fuel. Spinning the motor faster might help with the sensing of the slowing. Check voltage while cranking, should be over 9.5 volts.
Seasoned HDF Member
Joined: Dec 2005
Posts: 19,921
Likes: 8,027
From: poway
IIRC there was someone on the forums having an issue with the 570 cams in a 07-10 96 ci baggers without the comp change. 570s have bit later intake close than the 551s, so cranking pressure would be lower. Without enough cylinder pressure to slow the crank enough on the rear cylinder, the ECM does not know which cylinder is coming up on compression so it won't fire spark or fuel.