just bought 250r already have problem

Hello all,
I just bought a 2010 250r with under 300 miles on it. It is in great shape, extremely clean. When I went to buy it all was good started easy ran great except battery was dead so we had to throw on a charger to get enough juice to start it. I trailered it home and it only had enough juice left to barely crank over but not start. I was anxious to ride it so I tried to bump start down a hill and it popped once but no start. I threw it on a charger and got it fully charged to where it cranks full speed but will not fire. I am hoping I did not ruin something bump starting. I have checked the kick stand and clutch swithches althoughthe neutral light is on so it should be starting without those. I am getting a spark but the plug looks way more black than it should. I am not sure if there should be lots of compression holding my hand over the tailpipe but it doesn't seem like a huge amount, I can smell fuel out of the exhaust so I think it is getting fuel, the fuel pump is definitely coming on each time I turn on the key and or crank the engine. I am wondering if anyone has experience with the decompression getting stuck and not allowing the exhaust valve to close fully(therefore causing the black plug)and reducing compression. Any help would be appreciated, I am starting to really question my purchase, I sold my old bike because I thought I would have zero problems with this one.
Thanks.

Get a new battery . I bet it is just a bad battery. You might also get a new spark plug.

Do the simple things first.

The WRR is a solid reliable bike. Sounds like that one has just sat around for quite a while.

I agree with the above:

Don't get too excited until you put a new battery in there (and the correct battery at that).
Basically, your bike requires a healthy battery to act as normal.

Also, with motorcycle batteries, once it sits around so much that is becomes discharged for long enough, it's toast and no amount of battery charging will make it work right again.
This is why a WR-250R Owner's Manual will tell you to charge your battery every so often if the bike sits in storage (AKA: not being ridden).

thanks for the replies. I had the charger on all night but also hooked up my portable jumper pack for my work trucks. It is definitely a bad battery but the jump pack has plenty of juice to crank it fast. I pulled the tank and the plug again and the plug is definitely fouled(black)and not sparking at the tip, however the coil is sparking healthy so I am running to get a new plug and see what happens. Does the compression release only disengage once the engine is running? I am curious because the compression with the plug out seems very low like the compression release is stuck open(which may be causing the black on the plug?).

I doubt it's anything too complicated like the auto decompressor.
It works as you're thinking, by deactivating once the engine is spinning fast enough.

New battery (I believe this is not an option, but something that obviously need to be replaced if you want the bike working properly).
New spark plug since you already have the old one out.
I'd also get fresh gasoline in the tank (siphon out the old stuff).

If I were to mess with anything else, I'd remove the air filter, clean it in solvent, dry it, oil it with some foam filter oil, squeeze out the excess oil, and reassemble.
That's a good idea because rodents love to make homes in places like dormant motorcycle airboxes, and if rodents chewed a hole in the air filter element (or anything else they can sink their teeth into), now's the time to find out.

thanks again to the replies, I dumped the gas and refilled, got a new plug and it started right up,Wheew. Now it's time to start with some of the mods the owner hadn't done yet and get riding.

Great news.
Have fun with the bike. :)

Excellent. Glad you got it going. Our faith in the WRR is now restored. LOL


FYI, I would still replace the battery. I would not trust it after sitting so long. Not good if it gors out in the middle of no where.

Yes I am replacing the battery, I had a feeling it was shot as soon as the seller couldn't start it even though he knew I was coming.