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Firstly: Before suggesting I use the search engine, I should make clear that I have. Extensively. I am stumped because of the combination of so many strange symptoms, each of which could be attributed to small fixes, but something does not seem right about the way my bike has been acting. So here it goes, let's see if any of you mechanics or DRZ riders can help me out.

Subject: 2005 DRZ400SM ~17,xxx miles -- bike is mechanically stock, only "mod" being fat bars. Motor was rebuilt around 14,000 miles under a previous owner. I myself have put around 2,000 miles on the bike in the last 4 months.

When I purchased this bike, I immediately began riding it everywhere as it is primary and for that matter exclusive transportation. I went on a couple of long trips (5 hour rides down the coast and returning a couple days later for example). These first few months the bike has been mechanically impeccable, starting every time first time and doing anything asked of it. Never had a dull moment.

I then left town a little over a month ago. I left bike in the garage, without a tender (yup, stupid). Since taking the bike out again around a week ago, countless problems have arisen, not just battery issues either.

TIMELINE SINCE TAKING OUT OF STORAGE:
First day back, bike starts just fine, battery SEEMS to have ample juice in it. I take it out and about for some errands, first location I park the bike (approx 10 min ride) and come back, it starts fine. Get back on the bike, ride approx 15-20 minutes to the bank, this time upon exiting the bank, bike will not turn over, it evidently does not have enough juice. No strange noises, just not enough power. I compression start it down a steep hill, takes MANY tries but eventually I am on my way, however after a couple minutes riding I lost all electrical power, bike is still running but now dropping below 5mph or going to idle will kill the power. Takes 3 more SKETCHY bump starts on the way home and running a red light or two to get there. None the less I pick up a trickle charger from a buddy.

I then left town for two days and returned, upon returning I pulled the battery and began charging it. After 12-15 hours on the charger (the next morning) I put the battery back in. Turns over and starts up fine, take it for some errands half expecting it to die out because I know a complete discharge on a motorcycle battery will pretty much render the battery worthless. I make my first stop again, starts back up fine. Head to my second destination with some time to spare so I take it down a long valley road, however at this point it begins to backfire quite a bit. Quiet backfires I might add. The throttle begins to get jerky but as of this point, Speedo and lights are still functioning. I make it do destination, backfiring all along. Immediately after parking, I try to start it again, just to get an idea of what to expect when i return to the bike. This time there is power but pressing the ignition creates what I can only describe as a quite audible spinning noise without turning the motor. My suspicion at this point is that the starter motor's teeth have been stripped due to it being an old component and having tried several times to start the motor with insufficient battery over the previous few days. Nonetheless a compression/bump start gets the bike going, I ride it all the way home with speedo and headlight functioning as well as ever. Immediately I put the battery back on the trickle charger. This was all yesterday, and so last night, battery charging I spent hours poring over the forums, wondering if maybe it's the starter, the stator, faulty wiring (which would explain the backfiring), rectifier/regulator.

But I am stumped because none of these problems, even when pairing up two of them (the most problems likely to be occurring simultaneously) would account for all of the strange symptoms as far as I can tell. Now I am no mechanic, but I do have a pretty good understanding of how a bike works and I am handy in the garage. Can anyone give me a hint here??

A few other things I should mention: Battery connections on the bike are clean, in fact they look damn good. It should be noted I have not had the valves checked and I do not know when the last time they were checked (putting that out there in case it could relate to backfiring?)

MY GUESS AS OF NOW: Is the battery is shit, and the starter is stripped. BUT how could this explain the backfiring??

Today I bump started it and drove it to the shop expecting to just by a battery. Kept power all the way there. Upon getting there the guys (not mechanics simply desk workers) shared my suspicion of the starter being a problem as well as a battery, however mechanics were tied up and will be for a week. Which is why I came here. To leave the shop, I bump started it and rode like hell to get home, however on the short stretch of highway I had to ride on (maybe 7 minutes worth) I was hitting about 75 according to the speedo when it started backfiring on a WHOLE NEW LEVEL. I'm sayin I have never heard it backfire this loud. And constant it felt like the motor was going to explode all together BOOM BOOM BOOM BOOM and the bike would feel as if it was going to shut off completely. But upon pulling in the clutch and coasting into the shoulder, the bike never konked out. In fact it stabilized and I continued to ride, and quite smoothly too. Taking my time, only going around 65 it would be smooth one minute then backfiring like a motherf*cker the next, again jerking me everywhere and feeling as if it was going to konk but never did.

That's about all I have to describe to you now.. any questions about the situation I will get back to quickly and i GREATLY appreciate any help or insight into the situation. I am not in a hurry to have a mechanic spend hours diagnosing this so I'd rather spend my own time first in search of a diagnosis. I am hoping this is simpler than I am thinking, and maybe battery lacking juice could somehow explain the severe backfiring? Starters are also not cheap, and on the parts lookup page at the shop, the piece I think is shot out is not numbered and not available for individual purchase.

So.. with all that said.. let's hear some opinions please..
 

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The first thing you should use is load tester to realy test your battery, is amazing how many problems you can have from a bad battery that you will never imagine. I had many problems on a sport bike that I use to have, so I change just the battery and the bike feel like new again, so maybe thats your case. If you change the battery, before install, make shure you charge it very well. Just a hint, GOOD LOCK.
 

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measure battery voltage while bike idles & at a few thousand rpms. should be at least 14vdc. then test your stator for output voltage. if thats good, then test your rectifier. its got to be one of the two
 

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My old drz had some similarly weird problems, it indicated no charging of the battery (from a voltage test) and had some other odd electrical issues. I thought checking the charging voltage would help but it ended up being the battery was partially internally shorted somehow. I only realized it when it ran fine when connected to a jump pack. I miss my old drz, need to get another sm.
 

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My Guess is --
flywheel screws in the starter gear have backed out / snapped and killed the stator --

Dont take it for granted that the previous owner has done the loctite fix to the starter gear bolts--

Suzuki as far as I know has not seen it necessary to fix this Well Known Flaw in their assembly of the DRZ -
 
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