Well here is a new...I think. After several attempts to diagnose a e-starter issue, it turns out that the starter is spinning the wrong way. Go figure. Apparently brushes will wear down enough to still spin but depending on the polarity and location they can actually combine to spin in reverse. Add that one to the list:)
Well, it was only a matter of time before my starter clutch "gave up the ghost" as well. In my case, the symptoms were that the starter just spun without engaging/rotating the crank at all. This guide has been a great help so far in performing the repair. I did not want to use the crankshaft locking bolt (in fear of damaging the crank web), so I improvised a holder tool out of a pin wrench. The pins (6mm in diameter) fit nicely in the small holes in back of the magneto (where to official KTM tool would fit as well...) to hold it in place while wrenching the nut off. One must also remember that the nut in this case has a reverse thread. Actually removing the magneto was easy with the right puller. (Well, actually the loud popping sound that the magneto made when releasing its grip on the crank's taper freaked me out at first...) M33x1.5P (rh) is the correct size. The KTM puller kit includes some kind of protecting sleeve for the end of the crankshaft. The generic, no-brand puller that I bought did not have any protecting sleeve, but worked fine regardless. What set me back most is the fact that the worn out sprague clutch had already roughed up and gouged the corresponding surface of the 79T-free wheel gear. (This was mentioned earlier in this thread as well?) I tried to smooth these gouges out with some fine wet-dry sandpaper. However, I now fear that to make the surface completely smooth again, I will end up taking too much material off for the starter clutch to work. On the other hand, if I leave the surface as it is now, the roughness will cause quick wear on the new sprague clutch. A new 79T-free wheel gear will set me back more than 100 euros. I wonder if replacing the said gear is the only way to guarantee any longevity for the new sprague clutch? I will post pictures of the worn out surface later. Cheers, Tseta
A 1/2 copper tubing cap fit nicely over the end of the shaft to protect the threads from puller damage.... A lot cheaper than the oem $25 part...
As promised, here are some pictures of the rough, worn and gouged surface of the 79T free wheel gear. In these pictures I've already sanded the surface down a little with fine wet&dry sandpaper. Does it look too bad? Cheers, Tseta
Well, I've ordered a new 79T free wheel gear. However, I will soon be leaving on a longer trip to Russia and that part will not arrive in time. Therefore, I have now assembled the bike back together with a new sprague clutch and the old gear. I guess only time will tell how long this shady fix lasts. The few tries I dared to do with the starter showed that the new sprague clutch works fine: the starter spins and engages the crank, turning the engine over and effectively starting the bike. To give the sprague clutch and free wheel gear the best chances for survival, I've decided to always try to start the bike with the kick starter. If my leg gets tired or I need to make a fast getaway (), I think I will use the manual decompressor to allow for the starter to get the engine spinning with some momentum and then release the deco to get the engine to fire up. Thoughts? Cheers, Tseta
it doesn't look that bad to me and if it works, don't worry so much about it. that said, it will obviously last longer if you kick start the bike and save the button for when you truly need it. nothing wrong with kicking it over like was done on all these bikes prior to 1997. more manly that way, too
I tried your fix and replaced the starter brushes and it still makes a god owful noise when I try to start it any suggestions? Thanks Steve
I am experiencing some starter clutch problems as well, last day , tried to start with the E-start, nothing, then the kick-start with decompreser lever, I had more trouble than normal to turn over the kick starter. E-start didn't do anything anymore. After some backfiring and excersising my legs, I finally got my little beast on the going. Went home, and after trying again on the E-start. I just heard some sissing sounds. Like the starter is going around but doesn't pick up the gear-wheel. hope the flywheel isn't too damaged nor the gear-wheel. I don't have the time to repair myself, hope to see at the local shop what seems to be the problem. And hope more that the bill will allow me to buy any more beers......
my bike shop saw some real shit: the srews holding the starter clutch to the flywheel made a real mess inside. Rotor is totally wrecked flywheel is lost I don't get it why the srews didn't hold it.
My e-starter whistles loud and it turns itself around itself instead of firing the engine. Only can start when the engine is hot. Thanks for advice.
I would like to thank subscriber for tip on starter clutch I have just repaired my Sons LC04 Starter Clutch.I ran into one problem Luckily I bought 2 SKF seals. I used one to repair clutch an even though the engine was turning over ok there was still a noise, on dismantleing clutch I found the new spring loose in places I traced problem to the fact that there was a burr where the spring sat in some places I removed all parts and cleaned them up with a fine flat file checking that the spring sat in ok. On reassembly all was ok
I report it's done. The worst thing was a lack of tools. The metal spring was just stretched a little. Here is a short summary for all of you: * used buzzetti M33P1.5 flywheel puller. The flywheel nut needs a nice shot to move. * replaced metal spring from 56x70x7 seal. Best fit. The new spring diameter is 1.5mm, the old one was 1.5mm. I took 56 because 50 could be stretched too much and reduce it's life. E-starter is running like factory new. Thanks guys and special thanks to Losiu. You saved a lot of money. New starter clutch costs 100EU on auctions. I owe you a beer.
think I used a wrong word. it's not like save just to save. I should write waste instead. Who likes to waste the cash. I can only imagine how much beer is it for 100eu:eek1 Enough to throw a nice party I guess :) cheers
after a month of kickstarting the beast, and a bit of research, thx to the guys on here, i have just replaced parts 5, 6, 7, and 8 on the picture below. The sprag was shagged, as mentioned in this post, with the spring completely busted up, and the teeth on the clutch just fell out. I was initially only going to replace the sprag clutch #7, but my mechanic took one look at 6 and 8 and where the clutch had been engaging on their running surfaces, there was too much wear and tear. His opinion was that the sprag would only last a fraction of what it should if the repair was not completely done. Anyway, I now have my magic button back, and soon the parts bill wont hurt too much. cheers Truss
Mark up another satisfied customer for the Oil Seal spring replacement on the worn out sprague clutch. No more "clack" "clack" noise when pushing the e-start button. My spring looked exactly like losiu's on the first page. Thanks everyone for a great post!
I've done this repair twice now and the biggest problem I'm having is how to get the flywheel nut tight enough to quit coming loose. i've used an impact with locktight, long breaker bar while in gear holding down the rear brake, no worky, the nut just eventually comes loose and has now cracked 2 freewheels! Real situation when your on the HOV lane and it sounds like your case is coming apart! Mine is an 05 KTM625SMC, and doesn't have the bolt you remove to hold the crank.
The SKF Seal 19993 seal didn't do the trick. This post was quite helpful in identifying a tired spring as the problem. I'd held the sprague clutch in my hand previously and not thought to pull the spring. I replaced the tired spring with the spring from an SKF Seal #19993. Although the width of this spring fits nicely into the grooves of the sprague clutch, the diameter of the spring is quite a bit smaller than that of the original spring, making it a snug fit. When I put it all together, it was so snug that it clutched onto my free-wheel gear and would not let go, even when I took it all apart and tried using a wheel puller and teflon spacers. In the end, I brought it to Mr. Wizard, and he was able to separate them. I learned quite a bit in the process, but I am chagrined and perplexed by the result.
NEVER use the TDC locking bolt to hold the crank while torquing the magneto nut (or the primary gear nut for that matter, on the other side of the crank)! You WILL damage the crank and/or conrod by doing that! The engine manual makes explicit warnings against this as well. -T
