Ok...next question. Does anyone know the thread specs for flywheel/magneto extractor on LC4 640cc (01 DUKE II)? 26mm x 1mm right hand inner thread M26x1 RHIT Thanks
I have fixed my starter on the 97 rxc and have learned a great deal from this thread and from doing the procedure itself. LESSONS LEARNED: 1. the bike has the kokusan ignition, not the sem 2. therefore the 26 mm flywheel puller i bought was too small, it takes the 33mm puller described earlier in this thread. the one i found was off ebay and was listed for a late model suzuki gsxr 750/1000, it was $35 shipped. 3. the threads on the flywheel nut are reversed, confounding initial removal. that said an impact wrench loosened the nut without the need to hold the flywheel, crank etc. the flywheel came right off using the correct puller 4. all 19993 seals are not created equal. my carquest guy said he could cross reference that number but the seal he got me had a garter spring that was too thick. he got me a national seal rather than a skf 5. my spring was stretched but not broken. there was however a loose piece of the inner clutch retainer loose in the assembly, causing the horrid cacaphony whilst spinning. offending fragment removed and the scored inner surface of the flywheel surface smoothed with a dremel 6. since i had the bike apart and on the ground i was determined to think of a way to fix it, despite not having the right replacement garter. I noticed how the spring was made; there is one end of the spring that is of a smaller, corkscrew-type diameter that threads it self into the other end, forming a circle. viola: why not unscrew the spring off itself and shorten its overall length to tighten things up? answer: why not indeed. 7. one can shorten the spring by cutting the non-corkscrew end with a diamond dremel. shortened spring can then be re-installed. cost: $zero dollars, euros etc. starter works perfectly now 8. if your spring has not broken, you can keep things tidy during the spring removal process by using a rubber band in its place to keep all the little bits in their proper position in the sprag assembly. I know that my solution was probably only a temporary fix until i find the correct replacement spring but this solution might be a good emergency fix if you can't get parts or get desperate like me. I took pics of everything concerning the spring shortening if anyone has a desire to see them, i chopped about 2 cm off the old garter. it is just one more way to skin the cat. Has anyone saved their old sprag assembly, if so i could use the serpentine wire retainer that is on the inside diameter, holding the sprags in as this part is broken in my assembly. i guess I should just bite the bullet and get a new assembly but where is the fun in that? Losiu, sorry yours is broke again. Am i reading the caliper in your photos right? the correct garter is 1.3 mm thick?
what an ingenious pack o'weirdos you guys are! 2004 640A.. recently started to have the typical estart troubles reported here.... lotsa noise on the button... kids putting their hands over ears... dogs running away... etc etc. Am intersted in when this occurs in the bike's life cycle, mine's at 47000Kms and I've used the kicker maybe 1/2 dozen times.. always the button. I notice it's particularly bad when the motor is hot.. Soooo, new Sprag ordered... anybody with the 'right' kinda puller be able to show us some pics and specs? cheers!
Thanks for the great post. I'm only guessing that mine broke because the starter was working totally fine and then suddenly, out of the blue it started making that nasty noise again. Previously, the spring just stretched and, as you can see in the pic, was all twisted and battered. It happened gradually and I was still sometimes able to start the bike with the starter. This time it happened suddenly. I also have a piece of info, though. The ERIKS 50 x 72 x 7 seal (Dutch) has the right diameter spring. I can't tell you exactly how "thick" it is because I don't have a caliper that's precise enough. The difference between too thick and just right is really small. Since it's hard to find a place that has the right ERIKS seal, I asked about the 19993 SKF seal and they told me that such a thing doesn't exist. The number doesn't make any sense. I have no idea whether it's an issue with Poland or all of Europe, but such a part number does not make it possible to get the right spring. They didn't have ERIKS in stock so they sold me a $1 German seal with similar measurements (can't see the company name on it) and the spring is too thick. The measurements of this one are 50 x 70 x 8. If it turns out it's difficult for me to find the right seal again, I don't see how it's even worth the time to ride/drive around or even call a hundred places in order to find one. It only takes one trip or phone call to order the whole unit at the KTM place. After all, I know LC4s with 60.000kms on them and the sprague clutch works fine. Losiu PS. Can anyone post the measurements of the right SKF seal ? Thanks
Yesterday, I had to replace the whole sprag clutch with a brand new KTM unit &, unfortunately, the SKF spring fix was completely shot; bits of it all over the place in there (nothing left that would be measurable). I used another spring initially from a different company while waiting for the SKF to arrive; don't remember the name but still have this one intact. Measurements: - 1.52mm section diameter - 56 to 57mm OD (it was installed for a few days so it may be stretched a bit) Looks like the spring fix didn't last long since the excentric bearings slots were badly scorned initially ...thus grabbing & tearing up the new SKF oil seal spring. Hope this helps!
I think I have this correct: the smaller puller for bikes with SEM ignition or the Kokusan 4K-3 ignition, 26mmx1mm. (this worked on my 95 rxc 620 kickstart only SEM ignition) http://cgi.ebay.com/ebaymotors/KTM-EXC-MXC-SMC-SX-250cc-Flywheel-Puller-26mm-x-1mm_W0QQcmdZViewItemQQ_trksidZp1713Q2em153Q2el1262QQcategoryZ43977QQihZ021QQitemZ310083329969QQtcZphoto The larger puller for bikes with Kokusan 4k-2 ignition like my 97 rxc620, electric start. I think mine is identical to Losiu's which can be seen in the first page of this thread. the nut is much beefier and so are the flywheel threads, hence the bigger puller, 33mmx1.5mm: http://cgi.ebay.com/ebaymotors/GSXR600-750-WR250-450F-Flywheel-Puller-33mm-x-1-5mm_W0QQcmdZViewItemQQ_trksidZp1742Q2em153Q2el1262QQcategoryZ43977QQihZ021QQitemZ310082579549QQtcZphoto I bought both from these ebay listings and have used them both successfully on my two different bikes so I know they are correct. I'll work on posting pics of my spring shortening method. anyone care to correct me if i'm wrong about the two different kokusan varieties, 4k-2 vs 4k-3? since i haven't actually seen a 4k-3 and a lot of people have claimed that the smaller puller fit their bikes. dave View attachment 188772
Just a note on the spring, I don't know it anybody has touched on this and if they have forgive me. The springs in the seals are made linear, if you find the correct coil diameter you can shorten them to fit your needs. The springs have a slight taper on one end and are threaded into the other end to make a circle. If you look closely you can find the end of the outside end.
Orright, my update, a few points to share Eventually got the flywheel off to find... drumroll, please... the needle roller bearing supporting the starter gear wheel was absent :huh Not broken, disintegrated or anything - completely missing. I've had the bike from new, so it's been missing ex-factory. The seal saga; I too went in to my local SKF-badged dealership wanting a 19993 per this thread, which I cross-checked on the SKF web site. They sold me a NAK seal - saying the SKF part number didn't exist - cheaper and the comment was "they're all the same" but discovered later it had a thicker garter spring. Checked the web, yep the 19993 is listed. On the second try, I insisted the part number was valid - yep, they found it, there was one in the country and I would have it overnight... grrr! The SKF was clearly better made and more than double the price of the NAK :eek1 Starter clutch "pawls" were beginning to break down. They had flats top and bottom and some had lost their hardening. Also, the top surface either side of the U-channel for the spring had burred over, making the U-section look more like a teardrop with a narrow top. Removing the spring meant damaging it, I suspect that the other kinks in the spring were due to the burrs damaging it in use, like I did trying to extract the spring. Crudely filed out the channel so it wouldn't catch the new spring. Everything else looked polished smooth, so I reassembled it with a new needle bearing. Hit the starter, and... nothing! Well okay, the starter motor was free-wheeling. Looks like the only reason I was getting the starter clutch to engage was because the gear wheel was flopping around on the crankshaft, I suppose the skewiff loading helped it to engage? Anyway, now I am up for a new starter clutch, probably new starter gear wheel as the hub outer surface that engages the starter clutch looks very worn. I presume they are supposed to be flat, not having a trench in the hub, reminiscent of a worn brake disc? Hopefully not a new flywheel hub, too. The bike sounds a little less rattly now, particularly at idle and when being kicked over. Or I could be imagining it.
I don't know too much about KTM's. I looked up the part numbers for both the stator and the flywheel on my KTM DUKE II LC4 640 (2001) SKU: 58439005100 FLYWHEEL KOKUSAN GP9128 '97 SKU: 58439004000 STATOR KOKUSAN LOOSE '96 You were using reference to kokusan 4k-2 and 4k-3 and I'm not sure what those numbers are. I just need the right flywheel extractor and I don't feel like spending $52+shipping for an OEM one. Any help is greatly appreciated. Thanks
short story: pkrasko, get the big puller described above, 33mm. long story: as applied to 620/640 engines, not sure about the 400s; ignition identification by looking at the right side cover over the stator Early lc4s all came with SEM ignitions, right? these engines have the timing aperture (the little screwed on cover)on the stator cover at the 7:30 position. these bikes all have the weak electrical output and are most likely kickstart only. ie pre 97 rxc, pre 99 sc etc, dirt only machines, race bikes etc. these take the 26mm flywheel puller in 97, electric starter was introduced, so ktm upgraded to the kokusan 4k-2. these engines have a sight glass on the stator cover at about 12:00. the new ignition gave much more out put for the lights, starter, bigger battery etc. most readers in this forum are going to have this one, it takes the 33mm flywheel puller. Most readers of this thread obviously have electric starters as well. but the competition dirtbikes still had the crappy SEM until 99 when ktm started using the kokusan 4k-3 on these. these bikes are probably kickstart only units, the timing aperature is at 9:30 position on the stator cover. Since I haven't seen one of these flywheels, I am making an educated guess that these take the smaller puller as it looks small in the picture in the manual and because the torque for the flywheel nut is the same as for the small SEM unit. Look at your stator cover, see where the timing aperture is located on the face of the cover. That should tell you what ignition you have. Select your puller accordingly. To triple check, you can remove the cover and measure the flywheel thread diameter with a vernier caliper. If your bike doesn't have electric start, you aren't going to have oil around the ignition, if you do have e-start, you can lay your bike over and work on it on the ground. you might want to take your battery out but I didn't. Just dont drop anything as gravity will help it into the engine. As you can see from my profile i am but a noob so feel free to correct any misinformation I may be disseminating here. I have read this entire thread many times and have not seen a definitive proclamation that a 26mm puller works on an e-start bike, if I'm wrong, let us all know so we can disregard what i've just typed. dave
Dave thanks for your summary, looks correct to me. One further comment: I did the job (twice) with the bike on the centrestand and it only lost maybe 100mL of oil tops the first time, just a dribble the second. It didn't lose enough to get to the low level in the sight glass, nor make me top it up between times, when I've ridden the bike on short easy trips. For that amount of oil loss it's not worth draining the oil or laying the bike on its side.
All confusion has been cleared. I really appreciate it. I don't think I will lay the bike over to do this. It doesn't seem to make sense for a job that shouldn't take too long and then you have to deal with oil, battery, etc.
Hey guys, I just did the fix again. After c.a. 10.000kms the previous spring broke. After a closer inspection, it turned out that id didn't really break but got "unscrewed". It's possible to screw one end on top of the other and probably re-use it but I already had another O-ring seal that worked. On the seal it says: INCO A0 - 50 x 70 x 6 / 10,25 I'm guessing that the measurements are the ones next to the "x" signs and te "INCO" could be the brand, but not necessarily. (the total width of the seal is probably 10,25mm because it has a sort of "collar" sticking out of it) The trick about the O-ring seals that have the right spring is that they have to be as thin as possible. The ERIKS seal was 7mm thick, other 7mm-thick seals usually have a thicker spring. This seal is 6mm thick (with out the collar) and I think that a seal this thin will almost always have a spring that has is the right diameter. The shaft diameter that works is 50mm (for the seal) The total repair time (including pulling out all the wrenches and picking up all the metal blocks and putting them into the spraugue clutch) was 23mins. I confirm that there's no need to drain the oil. All you need to do is unscrew 4 bolts to take off the flywheel cover and than take off the flywheel. The work is clean and easy. I lost about 4 drops of oil. The bike starts no problem. I paid $2 for the seal. Cheers, Losiu
7mm and 6mm is little thick for spring (~1/4 inch)... Is 0,7mm and 0,6mm correct? And yes, 50 x 70 x 6 is size in mm (collar not includet).
Sorry if It was unclear before. I edited my post to make things clear. I meant the thickness of the whole O-ring seal :) [the thickness of the spring itself you can more or less read on the caliper in one of the pics in the 1st post] L.
View attachment 190511 Check this out. Here is my sprag assy., also the spring I chopped short to tighten its grip. Its shown in its linear form before I coiled it back onto itself, notice the amputated portion off to the side. I re-installed this spring and the starter works great. The thickness of the OEM spring is 1.4 mm. Next to the sprag is the garter spring from a seal that was too thick; 2mm. What you are looking for is a garter spring from an oil seal made for a 50 mm shaft of some sort, that is the critical diameter number. That's close to 2 inches for us non-metric folks. What sort of things have 50 mm shafts? -50mm white power fork dust shields. somebody measure the garter thickness on these for us, I bet any brand of motorcycle fork seal in the 45-50mm diameter might work -2 inch axle bearing seals for cars or trailers I'm sure others can think of other possibilities and examples. I only bring this up for the poor guy who is stuck with a glassy-eyed parts dealer that says they can't get the magical SKF 19993. Armed with this knowledge and a vernier caliper you can start rummaging through seal boxes and find one that will work for your poor disabled bike. Soon we will have multiple known options for even those across the pond and down under. The guessing will be over.
thanks all you Guys, in particular Losiu and dentvet! Replaced the spragg clutch today after picking up a magneto puller from the local dealer ($70 and no 6 week backorder.... ) Rattle gunned the nut of the end of the crank, popped on the puller and presto... the little 'spragg bits' in the clutch assy were visibly worn and the spring very sloppy. Inner surface of the freewheel hub was marked but still smooth, could see chatter marks left by the spraggs as they grip and slip as the spring starts to lose tension.... BTW warewolf, you mentioned.. "Anyway, now I am up for a new starter clutch, probably new starter gear wheel as the hub outer surface that engages the starter clutch looks very worn. I presume they are supposed to be flat, not having a trench in the hub, reminiscent of a worn brake disc? Hopefully not a new flywheel hub, too. '' There's supposed to be a small lip at the outer edge of the inner (drive) surface on the freewheel (creates the shallow trench).... the spragg circlip snaps in behind this... making sure it's fully seated.... see Losiu's pic below, in the earlier post.... Out with the old, in with new, 10 minutes reassembly an' it starts like new, off the button - Hooray! If anybody in Aus needs a (loaner) magneto puller, pm me. cheers!
Not sure we are talking about the same bit. The clutch inner grabs the outer surface of the extended hub on the gear wheel driven by the starter motor. It's the gear's outer surface that is worn. Part no. 6 in the pic; the hub extends away from the viewer so is not obvious, but it slides inside the starter clutch part no. 7. My bike was missing the needle bearing, part no. 5. btw I don't recall a lip as you describe on the flywheel hub, but I will check for it when I replace the starter clutch.
