Jump to content
Sign in to follow this  

battery issues

Recommended Posts

My 04exc doesn't start quickly with the button. I thought I read on here that the 04 had a borderline battery and for 05 they were going back to the "5" battery instead of the "4". If this is the case, can I put an earlier or later battery box in and run the larger battery?

Thanks.

Share this post


Link to post
Share on other sites

I think I read that you may have to mod the seat base a little as the 5 is a little taller.

Share this post


Link to post
Share on other sites

Yea, I think the 03 and eariler battery is too big, I think there is a aftermarket batter with more juice. I too want mine to spin faster and I have mine on the battery tender before every ride. It's always down to about 80%, so I think after 4 rides your battery would be dead.

Cheers,

Share this post


Link to post
Share on other sites

another best-guess...; was having starting problems with my '02 EXC400. starter just wouldn't pull over TDC, unless it "had a run at it". a couple other RFS's in the club having same/similar problems. tried a new battery (OEM). tried cleaning up all the electrical connections (re-install with conductive grease). even installed a new starter. all with limited results. charging system tested fine (volt meter across the battery leads at hi-rev's, showed 14.25 volts). recently, thought i'd take a look at the flywheel & coils. you know that black sludge that sticks to the magnet of your oil drain plug? that stuff was built up all inside my flywheel. clutch friction material? at least semi-metalic, or it wouldn't stick to the magnets on the inside of the flywheel. was thick enough that i think it was making contact with the ends of the coil cores. might have been grounding/compromising the charging system. not enough of an electrical connection to kill the charging system altogether, but enough that it wasn't throwing enough charge at lower rev's. anyway..., clean it all up. last ride (ETRA's infamous till-u-puke with lots of slow, low-rev running & lots of stalling & starting) and no starting problems at all. started right up first-time every-time. it'd hang a little bit at TDC but pull right through it (maybe the result of an already weakened battery, that just wasn't recovering with the sporadic charge?). was the build-up of black sludge the culprit? can't say for sure. but since cleaning it off the inside of the flywheel..., my starting gremlins seem to have gone away. keeping my fingers crossed. it's an easy inspection. you might take a look!

Share this post


Link to post
Share on other sites

on my 04 525 ,which i presume has an identical battery box to the 450, i replaced the stocker with yuasa battery # ytz7s. It is slightly taller but fits fine and throws off either 2 or 3 times the cranking amps. On my bike the d/s kit just took too much and the stocker was too weak. A related consequence was stress on the estart gear from low cranking output that resulted in a broken gear tooth.Not what you want floating around down there. I have read of a few other's w/ similar break.

Share this post


Link to post
Share on other sites

FYI from the Yuasa battery manual:

YTL4-BS: L=4 1/2 W=2 13/16 H=3 3/8 CCA:35

YTX5L-BS: L=4 1/2 W=2 13/16 H=4 3/16 CCA:70

YTZ7S: L=4 7/16 W=2 3/4 H=4 1/8 CCA:130

Share this post


Link to post
Share on other sites

Valves out of adjustment can cause this problem, too. When was the last time you set them?

Share this post


Link to post
Share on other sites

I set the valves 2wks. ago (.005" all around) but I think I got a couple kinda loose so I'm going back in tonight.

I think most of battery issues stems from the fact that my 04 was a left-over and sat in the dealership long enough that the technician had to put "boost charge" on it when I took delivery. I don't think the battery had a real chance at life.

I'm going to put a RTX5LBS in it tonight and see how that works.

Share this post


Link to post
Share on other sites

I compared my 04 EXC with my buddy's 05 MXC: The batteries are the EXACT same model. However, the battery box on the 05 is bigger--suggesting that a larger battery COULD be used. A KTM dealer told me that the 05 battery box is about $10 and bolts right into the 04!

Share this post


Link to post
Share on other sites

I did a little home work on this a few months ago. Do a search in the archives for "definitive battery info" That should answer most questions.

Brn2rde :cry:

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this  

×