Running a capacitor in paralell with battery?

[jstone8952]

Hi,
Im new here but Ive been lurking and reading for a while.
I got my 1st VMax about 4 months ago and absolutely love it. Only problem Ive had is what seems to be the all too common starting problems. When I bought the Max the P.O. had it on a battery tender and it started great, hot or cold, every time for the first month.

He was on hard times when he sold it and decided to keep his tender to make himself feel better about the deal, which was fine with me as I assumed the bike wasnt ridden much and I was going to be riding it every day, keeping the battery charged w no need for the tender.

After about a month I was riding home after a ~20 mile trip and it died at a stop light. I had a hot start issue with my GSXR, VF750 AND my GS700E, so I figured I'd wait a while, smoke a few cigs and try it after that, and it worked, but as soon as I pulled on the highway my damn fuel light came on so I pulled off for some $5/gal gas and the thing dies rolling into the gas station. Filled 'er up, hit the start and got a sluggish few turns of the starter, then a whole lotta clicking from my relay. The ride to the gas statio. should have been sufficient to charge the batt, so I figured the starter was hot and drawing too much to start.

Two hours, half a pack of Camels and two Redbulls later with no luck starting it I awkwardly lugged the 600lb monster to a side street and after a few failed attempts and a near drop I managed to push start it.

This situation happened 3 or 4 more times before I could scrounge the cash for a new battery as I thought this was the problem. Volt meter read 12V off, but dropped to 7 or 8 when trying to crank hot. I also took the starter out (what a stupid place to put a god damned starter!) and it looked fine inside, but I cleaned it up anyway.

New battery worked great for abt 3 weeks. I also bought a 1.5 amp tender and kept it on that if it was going to sit more than a few days. Bike now never starts when hot (I dont even try anymore) and occasionally wont start when left overnight.

Having now read my entire life story, Im sure youre ready for me to cut the BS and get to the point. I was wondering if anyone has ever run a capacitor in paralell with or in place of the battery on a VMax. Ive done a little searching and have seen on a few forums that it is possible to do both, but I have found the Max to be a quirky bitch and I dont want to run the risk of frying a harness if one of you geniuses has already fried yours for me.

Thank you for your time and any input!

-Kristofer

 

[MaxMidnight]

Fiest, welcome to the site.

To answer your question, no, I have never read of anyone using a capacitor. I guess there has to be a first!

However, before you go that route, have you established what is causing the issue?

The pre four brush motors can be reluctant to start when hot but they are fixable.

Starting with the obvious - have you removed and cleaned all of the earths and measured them for high resistance?
The fact that you seem to be getting a significant voltage drop suggests there could be an issue here.
Also check that the headlamp goes out when cranking.
Remove the R/R off the back of the footrest mount and thoroughly clean the contact areas as it earths through the hanger.
Better still run a separate earth lead from one of the mounting bolts to the main earth.

I know you have had a look inside the starter but also have a read of this which explains how to put an earth tag between the brush plate and starter body. I'll assume that you have confirmed that the brushes are OK and the commutator doesn't need undercutting.

Can we assume that the battery holds its charge?

Check the battery voltage when the motor OS running - it should be between 14 & 15 volts (no load) @ 5000 r.p.m.

Check that the 'crimp' have been soldered.

If you still have low charging issues then work through this.

Hopefully the above will sort your issues but should you still be in the doggies doos then there is always the option of fitting one of the later four brush starter motors which can be identified by the SM-13 stamping.

Additionally the Odyssey PC680 battery also assists staring, hot or cold.

 

[sdt354]

I wouldn't do that, with a capacitor. You'll be burning out all kinds of components. A starter needs currant to crank strong. Spiking the voltage will lower the current. By current I mean amperage.
Check our threads on charging systems. You'll find most of us have had issues to address electrically. Most common is high resistance caused by dirty and corroded connections. The battery was probably needed when you bought one anyway. I never trickle charge my battery. I never have to.
Start with a voltmeter at the battery. Overnight, no charger on, voltage? Then voltage at idle, then at 2500 rpm. A fully charged battery that sat overnight, without a draw on it should be 12.5 minimum. Voltage at idle should be at least 13+ volts or better. A good system at 2500 RPM's should be mid to high 13's and ideally 14 volts. All are average readings. Others will chime in with good information. There is a lot more for sure.
Steve-o

 

[sdt354]

If you have an 85 regulator? They weren't very good pre 96 I believe. The newer type are more desirable and plug right in. Much like Steve's mention of the newer type starter. The newer type have an important,additional ground connection that eliminate the body of the regulator through the peg bracket, from being the only ground.

 

[mr.maxx]

capacitors can only store electrical energy for a very short period. i honestly dont think it would hurt anything if done properly....however i dont see any benefit. and a capacitor will certainly not store enough energy to start the bike without a battery.

 

[jedi-]

I've been down this road with a hot start problem and there's a bunch of info here.
I have the older type starter but really found my issues was the charging circuit and fixing some poor earths.
Have a look at this guide for example....
http://www.vmaxforum.net/showthread.php?t=19108

 

[SpecOps13]

I put a newer 4 pole starter on my 89. It spins over much faster when cold or hot now....
No more starting issues.... I don't think even a huge capacitor will help...

 

[bazwell]

Just no on the capacitor. They lose energy faster than a good battery.
What you need to do is look at getting the power from the stator into the battery. That's what the suggestions above ^ are regarding. All of those things have merit.

I have an '85 with the original 2 brush starter, and it already had a regulator from a different model. A new battery and good fat wires made it good. Direct wiring the regulator to the battery (with a fuse) and making sure all earths were real good was probably the best.

 

[naughtyG]

I'd say no on a capacitor on mr Max as well.

You definitely have bad earth / charging issues.

Check all the suggestions made already - cleaning the bad of the RR and doing the crimp fix are solutions that could help you and cost near to nothing - defo well worth doing!

Also being in Tampa you have Captain Kyle very close (Oldsmar) so there's the best help you could hope for if you feel stumped about any of it!

 

[ninjaneer]

caps only supply short bursts of energy, they dont increase your battery bank. done in the auto stereo arenas to overcome the demands of pushing woofers to reproduce beats. i forget my circuit and electonic devices theory, but the discharge of a cap is like a delta spike and then there is a momentary lapse of contribution as the cap recharges. the frequency of energy spikes isnt fast enough to emulate the continous waveform required to turn the starter. its been a long long time since i studied the material and i most definately could be misguided.

to relieve your hot start problem is to maximize the charge on the batt when your fan is on. to do this, remove as many lossy connections,make sure your grounds are clean, increase the gauge of your reds and blacks, upgrade your r/r, check your stator and replace with higher output if it is kaput. there is a great sticky in the how-to section. i highly urge you to visit it and perform the steps.

Regards from my Taptalking Hercules Android

 

[shawn kloker]

get the Odysee battery too. Huge difference.