HAWK on the COBDRI

[PalladinSC]

Many thanks. I'll be diving into tracking wiring today.

[Ariel Red Hunter]

Originally Posted by goat67

Minor correction to this operational description regarding this sentence.

The other coils are used to charge the battery, and runs the lights via the zenor diode that converts the ac to dc, so that the battery stays happy.

To convert ac to dc requires a rectifier which consists of 2 diodes for a half way and 4 diodes for a full way. A zener diode on the other hand is used to clamp a voltage at a set level these diodes come in various voltage ratings.
A zener can act as a regulator a very simple one. Usually a regulator uses a few more passive components. We just see the heatsinks on ours.

Thank you for the correction. I knew there was a rectifier in the circuit, but my mouth worked before my memory...ARH

[PalladinSC]

Well, after pursuing possible ignition problems (new ignition coil, new CDI, checking magneto coil) to no avail. I went looking into other sources. There can only be 3 causes: ignition, fuel, compression.

Ignition had been ruled out by the above attempts.

Fuel was also ruled out as there was excellent fuel flow from the tank into the carb float bowl.

This leaves compression. I pulled the valve cover to check the valve clearances. Exhaust was good but the intake valve keeper (apparently) failed and the valve had dropped into the head and was bent. Fortunately, the piston seems to be undamaged.

Now to get the necessary parts and try to figure why the keeper failed.

[goat67]

Originally Posted by PalladinSC

Well, after pursuing possible ignition problems (new ignition coil, new CDI, checking magneto coil) to no avail. I went looking into other sources. There can only be 3 causes: ignition, fuel, compression.

Ignition had been ruled out by the above attempts.

Fuel was also ruled out as there was excellent fuel flow from the tank into the carb float bowl.

This leaves compression. I pulled the valve cover to check the valve clearances. Exhaust was good but the intake valve keeper (apparently) failed and the valve had dropped into the head and was bent. Fortunately, the piston seems to be undamaged.

Now to get the necessary parts and try to figure why the keeper failed.

Ah crap this is a bummer.

[Sport Rider]

He sent me a picture of it. aw crap is right!

[PalladinSC]

I will confess that I'd been running the crap out of it. I strongly suspect that I over-reved it at some point. I'd been running it at WOT for over 25 miles. I think I failed the bike more than the bike failed me.

[L00N]

did you have any mods done to the bike for the bdr? did you trailer down to durango or did you start near steam boat? did you have luggage on the bike or was that in the support vehicle?

we are talking about doing the bdr starting from denver >durango>steam boat>denver but i wasnt sure if the hawk could handle that.

[Pathfinders]

Originally Posted by goat67

Minor correction to this operational description regarding this sentence.

The other coils are used to charge the battery, and runs the lights via the zenor diode that converts the ac to dc, so that the battery stays happy.

To convert ac to dc requires a rectifier which consists of 2 diodes for a half way and 4 diodes for a full way. A zener diode on the other hand is used to clamp a voltage at a set level these diodes come in various voltage ratings.
A zener can act as a regulator a very simple one. Usually a regulator uses a few more passive components. We just see the heatsinks on ours.

Half wave and full wave refer to the Sinusoidal AC waveforms.

[severely]

Originally Posted by PalladinSC

I will confess that I'd been running the crap out of it. I strongly suspect that I over-reved it at some point. I'd been running it at WOT for over 25 miles. I think I failed the bike more than the bike failed me.

Do you mind if I asked a couple questions? Was your CDI/coil stock or aftermarket? Were your valves adjusted before the trip? Anything else we could learn from? Thanks, good luck on repairs.

[Hammer13k]

Ouch well at least you found the issue, sounds like it's time for a ported head and cam.