Battery v. Capacitor

schlakeandbake308

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I wanted to post this so guys building their bikes have an idea of what to expect. I just wired in a battery in line with a sparx tonight. I had a sparx only, pma and pamco. Kick only. So I'm going to post how it rides with both.

Capacitor
Bike ran... That's about the best that can be said. Setting carbs up (mikuni roundslides) was a bit of a pain. I was all over the place getting them working. I thought it was running rich and kept dropping mains. Very frustrating, never could get it right. Stalled at stopsigns, a lot. I have a rephase with serious porting and a shell #1 cam and a big bore kit. Honestly I think it was running better stock. No matter what I did to the carbs, I still couldn't get much over 5500 rpms. It was a blast to ride, but I felt like I could do more

Battery and capacitor
Wired it up so that the battery and capacitor were in line. Kick over to a perfect idle. This has been a struggle from the start. Best idle I've had in 600 miles. So then I reset the advance and valves. Took it out for a little spin. Never cuts off at any stopsigns, headlight stays lit! Sounds better, take off is better, and jetting is a breeze. I figured it was time to let her rip. This is where the craziness come in. I swear, the motor hit 8k rpms in about a second and a half. This thing is an actual rocket. Such a fun ride. I'm unbelievably happy with it. It begs the question... Why was I screwing around with the damn capacitor to begin with!? Trust me guys, run a battery, it's so much better. Battery is a 12 0.8ah I got for 10.50 on eBay. I hid it under the seat in about 30 seconds.

If you are debating what to do with your Yamaha, the battery makes the pma work so much better. I couldn't be happier with the way this bike rides
 
... I have a rephase with serious porting and a shell #1 cam and a big bore kit.

I swear, the motor hit 8k rpms in about a second and a half. This thing is an actual rocket...

Haha, Jekyl and Hyde. Welcome to the club.

... If you are debating what to do with your Yamaha, the battery makes the pma work so much better. I couldn't be happier with the way this bike rides

Good tip!
 
Battery vs Capacitor is really no contest. A Battery is a source of power, which means it can supply current as well as voltage. A capacitor is a voltage device, which means it just can't do much work for you. These bikes need current just like we need food.
 
your results are interesting, almost the exact opposite of mine. i ran the same .08ah battery with a banshee pma setup,ninja reg/rec, and had stumbles,stalling, and what felt like fuel starvation at high rpms. I ditched the battery, got a sparx cap, and new PMA kit from HHB and it was like a whole new bike like you described. I forgot how quick these bikes were because I had been riding a dog for so long. One thing to watch out for with those small batteries is overcharging them on long rides, did that once or twice.
 
I have run into the opposite, go figure :laugh:

It is worth checking your PMA for proper output and condition, just to make sure.

AND, you can run both if you like, a Capacitor and a battery, that way if a battery craps out, you can still get home on the cap :wink2:

Hugh
 
i should note that i ordered two batteries, the first one didn't have a charge. it acted about the same as the Sparx capacitor did. I put the other on a trickle and once it was tried, with a full charge, it ran perfect. I already run the battery in line with the sparx, so that may make a difference as well.

My set up: HHB PMA, Pamco for 277 rephase, Sparx capacitor from lowbrow, 12v. 0.8ah "cigarette pack" battery.

I should have stated earlier that i had to charge the battery. it ran the same as the sparx with the dead battery in place
 
must be something wrong with your Cap or it's undersized, or loose connections etc... both my bikes run perfectly from idle to WOT on used 10,000uF caps- probably from power amps. I prefer the screw terminal type. great starting and no weak headlight at idle either.
 
This is an excellent case example to learn to use one of those ultra-cheep pocket-sized Digital Storage Scopes. It's simply a voltmeter, that shows voltage fluctuations over time. The DSO201 is all over eBay at prices down to $60.

Item: Mini Pocket-Sized Handheld Digital Storage Oscilloscope ARM DSO Nano DSO201

URL: http://pages.ebay.com/link/?nav=item.view&id=191819200940&alt=web

Alt URL: http://www.ebay.com/itm/Mini-Pocket...scilloscope-ARM-DSO-Nano-DSO201-/191819200940

DSO-201-p1a.jpg

They may seem impossibly complicated at first, but they're actually easier to conquer than most video games.

You would just clip the lead to the bike's battery or Sparx capacitor, and look for voltage fluctuations. Could help diagnosing a bad cap, regulator, battery, poor connections, ...etc. It's great to be able to "see" what's actually going on, versus guessing.

Imagine your "Impressive Dude" ranking improve when your friends discover that you have a high-tech oscilloscope. Plus, it's an additional item on your job application form.
 
its possible, just posting my results. i had another capacitor from tc bros that i never tried... maybe some experimenting will help. my sparx was brand new, but the rating on the tc bros was significantly higher
 
2Many- it's entirely possible that none of us have time to work with all the XS wrenching... :)

jtrip- hope those tanks and side covers etc... worked out for you. we're down here in Tarpon now. you could be in tuning hell by assuming it's the cap. any way to swap in a known good battery and bypass the cap for a high speed test run? what is the uF rating on that cap? could not find online...
 
schlake- that's about what I remembered. only about half what you should run from what I've read. I score caps on ebay, 10,000uf and at least a 25V rating or more. I mount them on a closed cell foam pad zip tied to something. works great.

high speed "misfires" can be hard to diagnose. I thought I had an electrical problem the other week but it ended up being a bit of crud partially blocking the float needles... old gas tanks are a PITA, even treated ones occasionally flake off some debris.
 
I'm with you on that with the carb crud, but the carbs are brand new. Plus the new battery solved my issue. But I bet a better cap would have handled it better
 
... I bet a better cap would have handled it better

Probably. There's members here that have no problems with the setup, others, not so well.

The interactions between a large cap, charging regulator (its response times), pulsed demands of the ignition system, and the sensitivity (if any) of the ignition's "brains", is a somewhat unknown here.

More war stories: http://www.xs650.com/forum/showthread.php?t=38758
 
schlake....i have a question for you on the wiring....on a new build just finished up I am running a HHB PMA, PAMCO, HHB reg/rec....LED headlight and taillight only and i followed the attached wiring diagram. did you wire in the capacitor then the battery or battery first then capacitor? Thanks....
simplifiedwiring.jpg
 

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There is no fuse protecting the Pamco on that diagram. The fuse on there will be a 20amp and there should be a 7.5 for the pamco

A lot of variations where the 20amp fuse is situated and lots of different views on the placement.
 
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understood about the fuse......what about the capacitor first and then battery or battery then capacitor?
 
For clarity's sake, I posted in direct reference to your statement " I followed the attached diagram"...................You didn't

On the battery or cap 1st or second, I don't know and im not looking it up. My guess is cap before battery.
 
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