Topic: Fuse goes to often what to do...

[Lykowsky]

Hi,

I have got such a deal with my cb500 that she is blowing out 15A fuse every certain amount of miles, 5 miles or so i haven't a clue why it is happening, i have to add seems like only when riding with lights on.

We can assume the current draw is to big assuming that i'm running Dyna 3 ignition with 3 ohm coils.

What to do??

[Johnie]

Not saying this is right, but I see guys put in a 20 amp to see if it still blows. If not, they just leave the 20 in there. Give a check to all the wiring in the bucket and try to be sure there is not a bare wire anywhere hitting the frame or shorting out. If it only does it with the headlight on then concentrate on those wires.

[fasturd]

I wouldn't put in a larger fuse. You have something drawing too much. Make sure you have the dyna hooked to a good power source. Make sure none of your power wires to your headlight are grounding. Make sure your grounds are good.

[TwoTired]

 You have a fuse block, or an inline?

Is the fuse blowing near the center or near the end caps.

You got a bigger headlight than stock?

Have the signal bulbs been changed to 1157/1156?

The 3 ohm coils and Dyna-s add about 5 amps to the stock current loading.  So, if you can keep your battery charged, increasing the fuse rating is probably wise.

[Gaither]

Lykowski

Get back to Two-Tired. He's trying to solve your problem/s but needs answers first!

[Lykowsky]

First big thanks for help 

Right i,ll start from the beginning.

Looks like i have fuse inline in that genuine single fuse plastic carier.

Fuse keeps blowing in the center of it.

To be honest i havent a clue about the lamp because it has fairing on it with different lamp, but i'll check the bulb power tonight.

Question regarding signal bulbs, i have to check them as wel because all signal indicators are not stockers.


I was thinking about some topics where was stated that 3 ohm with addition to dyna ignition draw more current.

The point is I cannot keep my battery charged riding with lights definately, so that is another problem to solve.

I was thinking of adjusting charging regulator unit but what i think it is not gonna be the solution for longer term.

I will definately start today with looking at the all wires and grounds.

[GammaFlat]

A general clean-up of the wiring connections is a good start when you're blowing fuses.  Each compromised connection between your power source and load adds to the problem.  Check your fuse housing as well.  Better, replace it.  Consider using relays and better wiring for the big load points (headlight and coils).  Moving everything back to factory specs would be great but sometimes not what people want to do.  Making the bike reliable is a good start. 

[Lykowsky]

     
     Definately clean up is good start so i'll do it first,

     Regarding the bike i have bought it as is, in not working condition but complete.
 I have replaced coils same with ignition, but due to those aftermarket parts there might be problems regarding all the aftermarket electric divices.

[TwoTired]

Fuse keeps blowing in the center of it.

That's an over current indication.

To be honest i havent a clue about the lamp because it has fairing on it with different lamp, but i'll check the bulb power tonight.
Question regarding signal bulbs, i have to check them as wel because all signal indicators are not stockers.

It all adds up.  Not hard to carry a 5 lb weight.  So you should be able to carry a hundred of them right?

I was thinking about some topics where was stated that 3 ohm with addition to dyna ignition draw more current.

Possibly, it was me.  My analysis shows, the Dyna-s/3ohm coils draw 94 watts vs the stock 33 watts.  

The point is I cannot keep my battery charged riding with lights definately, so that is another problem to solve.

The Honda shop manual says the 500 alternator puts out 150W at 5000 RPM.  (At idle it puts out about 1/3 of maximum.)

I was thinking of adjusting charging regulator unit but what i think it is not gonna be the solution for longer term.

VERY bad idea.  The regulator setting's purpose is to keep the battery from ever overcharging.  It cannot boost the alternator output, as that part does not determine maximum power from the alternator, it just keeps the battery from boiling out.  What you can do is measure the voltage across the Black and green terminals, and see how that compares to the actual battery voltage.  The regulator uses the power it sees to throttle back the alternator out put, so reported accuracy is important.  But, it also passes that voltage to the alternator so it can make power.  If the voltage is lower on the black, then it cannot stimulate the alternator into full output.

I will definately start today with looking at the all wires and grounds.

That's a good idea.  Let's say each connector or switch contact looses 1/10 watt.  Big deal you say.  But, if you have 100 connections that's 10 watts lost to non-useful heating.  That's the same as de-rating the alternator output from 150 Watts to 140 watts peak, and a 50 watt idle output to just 40 watts.

But, your biggest issue will likely be the ignition and headlight draw.  You can ameliorate the ignition by inserting a 1.5 ohm resistor in series with the 3 ohm coils, or swap them for 5 ohm coils.

Cheers,

[Lykowsky]

Thanks for help 

As soon as ill get some outcome ill post where i'm

TT i owe you few pints