1600 engine knock

[truckerdawg]

Engine cut out while running down the road. Bike was acting like the battery was the issue. Bike would reset each time I hit the starter. Got it fired back up and got off at the next exit. As I was slowing down, knock/vibration started. Feels like it was coming from the front of the motor.

Any suggestions on where to start? I am planning on trailering it home tomorrow.

[Idaho]

This has got be scary. I recommend that you send Macmac a PM to ask for advice.

Good luck and let us know how things work out.

[Cajunrider]

TD, do you have any remaining factory or extended warranty?

[dogdoc]

We hope you do.

[ells]

TD, Please let us know what you find, it doesn't seem like a common problem. What year? Any modes to fuel or air system?

[truckerdawg]

Got it home today. Definitly knocking on the front cylinder. When I try to start it the starter would click or turn over briefly. Know that the dreaded clock/trip reset kicked in(possible bad battery?). Have the service manual and found a variety of symptoms that could cause a knock but have not had a chance to inspect anything.

I had to run it to get it on the trailer. Did not hear any rattles and still had very good power.
Have not had an oppurtunity to check voltages yet, but do have the service manual and will start a tear down hopefully this week.

I am running a right side cadmann, with baggers and a resistor mod.

And no warrenty.

[ringadingh]

That can be a tough one to point you in the right direction without seeing it. Make sure the battery is charged up well, if it still knocks a lot you have to start elimating things, is the cam chain broken or possible that it jumped a tooth? That could cause it to do what you described. Id start with a compression check first. That would tell you if a valve is bent or broken also.

[phenrichs]

I wonder if it is an electrical problem. I was doing some maintenance and foolishly forgot to plug in one of the plug wires on the front cylinder and when I fired it up it knocked bad. Your starting and quicking problem sounds electrical in nature. Perhaps you have a short somewhere that is causing you to loose the spark or get an irratic or off timed spark in the front. I would check for burnt wires or wires that have rubbed through the insulation and check all your connections.

[macmac]

The paint says 05/ 06 black and silver.

How many miles on this bike? That may indicate a bad timing chain, out past the chain limits, and perhaps a skipped tooth on the cog.

A weak battery, poor ground might cause a knock if the engine shuts off mid stroke and self starts again.

A surface reading of the battery is in order with a few other tests.

A surface reading is just done with the engine off, but not right after taking any charger off the battery.

If you take this reading with a charger hooked up and on, or right after disconnectiong the battery the reading is false and will be a lie reading to high.

If the bike is on a charger all the time, the way to get the right reading is to take a load test first.

To do that you pull all the plug wires off and while reading the meter and a watch crank the engine a full 10 seconds count and read the meter still cranking at 10 seconds time.

If that reading is less than 10.5 volts the battery is weak. If the reading is inder 8 volts the battery is junk.

Then wait 15 minutes to 1/2 hour with out the charger hooked up and take a real suface reading. That should be 12.4 volts and up to 12.8.

A digital meter is a must have for these tests.

Other possibles are counter weights rubbers coming loose, and even piston / rod slap if this engine was run with out oil... I am assuming running the engine with out oil is not the case.

If you buy a mechanics stethascope you can pin point listen to the engine. If you have a 12 inch long ratchet extention you can use that to listen with.

Rod ends and pistons once bad don't get quiet in any rpm range, but I don't think this is the problem. I hope not anyway.

With a ohm meter it might be a good idea to check the plug wires one by one, and wiggle them as you test as much as you can because a broken wire may make contact, when the reality it iit is broken inside.

The coil primary (small) wires should be inspected for being clean and on tight.

If this bike has driving. Passing lamps rated to 55 watts each or so, and are direct wired thru the ignition switch, the switch may be over loaded and fried.

This is pretty common when the passing lamps are hooked to be on with the key, and or tied into the main lamp with no relay.

Passing lamps can't share much of any other circuits with out a relay. ( I am just taking some wild guesses hoping to hit on something, as more details are needed for a better guess.)

[watchman]

I have never heard of doing a Caddman conversion with baggers and only doing a resistor mod. Have you been having a lot of engine pinging with that set up? What size resistor are you rinning?

[Todd]

Originally Posted by watchman

I have never heard of doing a Caddman conversion with baggers and only doing a resistor mod. Have you been having a lot of engine pinging with that set up? What size resistor are you rinning?

I had (and many have) that set up and did not even have pinging without the resistor. All of these bikes are different and they all do not ping. I did put a resistor in just to make sure I was getting a little richer mixture.

Put the TFI on for a little more performance now though.


I am thinking plug/plug wires/or grounding issue.