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  1. RE: counter boring for cap screws, the 159 and 199a castings are almost identical, save one screw hole nearest the kickstarter on the 199a cover. That one Bultaco chose to counter bore for some reason. Otherwise, all else appears the same. I will add that if purchasing a black-painted 199a cover, be prepared to spend some time at the polisher if you're after a mirror-like finish. Bultaco did not polish cases before painting!
  2. Confirmed - fits perfectly. No visible gaps - all screws seat correctly. I've included a pic taken through the access cover to illustrate clutch hub clearance. No contact there. When shopping for a replacement, definitely follow Feetup's advice in getting a measurement from the seller. Shouldn't be too much to ask of the seller if reputable. Cheers! C.
  3. Confirmed - measures from the gasket surface to the point mentioned. For comparison sake, I also measured the cover from my 199a. As you can see, the factory removed the step that can be seen on the 159 cover, gaining an additional 3mm clearance - 75mm depth total (attached). Does seem your cover is from another model or lost 5mms worth of material on a sanding table. Cheers- Christian
  4. Hi Phillip, Well... disregard what I mentioned about the distance between the clutch spacer and seal surface. My memory of working on the 159 was too foggy to accurately recall. I cracked open the clutch cover last night to take a few measurements and photos (attached). All seem to be in line with the measurements Woody provided as well as confirming his description of the 159 clutch hub (original to mine, anyway) incorporating studs with pin retainers NOT threaded. On the off-chance you simply have a weird clutch cover, I did measure mine internally using a straight edge and came up with 72mm taken from the ledge of the threaded access port for external clutch adjustment (see photo). Hope this helps a bit. Good luck!
  5. Hey Phillip, Looking at this photo, it appears that clutch spacer is either not seated properly or is too long (+ 5mm, I'm guessing from the look of it). From memory, I believe my spacers typically sit nearly flush with the top of the seal once seated. Yours appears to have significantly more clearance than I recall. This would certainly move the clutch assembly outward as you describe... but you also said the primary chain is presently in line with the flywheel primary? Could it be that you have two spacers (clutch and primary) that are of incorrect lengths if this is so? Time permitting I may pull the clutch from my 159 spare to measure what I have. I'll let you know what I find soon.
  6. Been following this thread and have to agree with Woody. If the primary is full seated and the primary chain is perfectly in line with the basket - exactly parallel with the edge of the case when looking downward over the chain - then the culprit HAS to be the clutch hub not fully seating. I don't recall from memory if the shaft on a 159 is splined or if the hub is held in position via a keyway, but it's possible either the key isn't lining up properly and stopping the hub from landing home or, if splined, if some material is preventing the hub from sliding into its fully seated position. It helps to take some tension off of the primary chain when positioning the clutch hub by securing the chain tensioner with zip ties to the frame (if still in the frame) or via similar method if out. That will reduce the lateral pull caused by the tensioner when positioning the clutch hub with its key or splines... and wlll make it easier to guide the hub straight through the basket bearing into its fully seated position. Out of curiosity, have you tried sliding the hub onto the shaft without the basket to test whether or not it's somehow getting hug up? Give it a shot and take a measurement of exposed shaft threads, then compare that reading to exposed threads with the basket in place. Hang in there - you will defeat this problem!!
  7. That's what I thought initially. But, no... no holes anywhere on the crank to plug this into. Nope. Tried that as well. Fantic actually offered a thick plastic disk with a large hole in the center for the rod and four smaller holes to accommodate the cylinder studs. Once slid over the studs and into position, you'd then insert a section of cylindrical aluminum through the pin end of the rod, preventing the crank from completing its turn when tightening or loosening crank nuts. Very simple and effective design, really. I'm beginning to wonder if something was either lost in the translation of the parts book from Italian or maybe a technical writer just made a mistake labeling it as a crank tool. Perhaps it was intended as a holder of some sort for removing the gear cluster as a unit once the shift fork shafts are pulled? Seems the shafts and this tool are of similar thicknesses? Unfortunately (or fortunately in this case as this motor took me much longer than it otherwise should have) I've already buttoned things up and can't test my theory. Anyone have a motor apart or an empty left-side case to take a measurement? Thank you for your input!
  8. Got that right. But it'll be so worth it once she's finished. I do the same myself. If I can't produce the level of work I'm after, I'll pass it to another who can - provided it's within my financial means to do so. If ya want art (and beautiful welding certainly qualifies in my book), it's best to leave the work to a true artist. And that's definitely some pretty impressive work you've got right there! Good luck with your build! Cheers - C.
  9. Wow - beautiful work! It's near impossible (okay - IS impossible) to see where you joined the old tubes to the new loop. Really well done! Looking forward to your continued progress. I'm sure she's gonna be a stunner when done. Enjoy the process ~ C.
  10. Hello All - Well, I finally made it through my first 240 motor rebuild - with much appreciation to those of you who helped me get there. Pretty straightforward though it clearly proved how manual-dependent I've become. Probably spent way too much time pouring over the parts schematics to confirm assembly sequence and to avoid leaving out any important shims or what-have-you. Question... While looking at the factory tools that were available and listed at the back of the parts catalog, I saw one in particular that has me stumped (see attached). Any ideas how this tool was used? I have one of these but, for the life of me, can't figure out what or where it was designed to fit. Thoughts? Best regards, Christian
  11. All excellent suggestions here. I've done the same, beginning with what Woody suggested: " If the cone shaped bump stop is removed from the bottom of the damper rod, the rod can be removed by sliding up and out of the top of the stanchion ( in ordinary circumstances) leaving the alloy spacer in the bottom as that part will only come out of the bottom. To accomplish this, I use a vise, a relatively long 8mm hex bolt, a rawhide mallet and a propane torch. 1. Thread the long-ish 8mm bolt into the end of your damper rod. 2. Open the jaws of your vise and clamp tightly with the aluminum bump stop to one side of the jaws and the stanchion end to the other. Hopefully your vise is of the size that will allow you to do so. If not, you can likely rotate it or the fork assembly into a position that will help you to accomplish the same task. 3. While self-supporting, apply some heat to the bump stop with your torch to expand the aluminum a bit (not too much, as there's a small rubber gasket within that you don't want to burn.). 4. Once heated, SLIGHTLY LOOSEN the jaws of your vice just wide enough for the damper rod to slide between but NOT wide enough for the bump stop to pass through. The idea is to use the vise as support for the bump stop as you drive the threaded bolt through (and damper rod OUT of) the bump stop. If the jaws of your vise are too tight, you could mar the surface of the damper rod - too loose and there'll be insufficient surface area to properly support the thin aluminum end of the bump stop you'll be hammering against, potentially causing surface damage to the leading edge of the aluminum. 5. Supporting the fork assembly within the loosened vise in one hand, with the other use your mallet to hit the bolt you've threaded into the bottom of the damper rod hard enough to drive the damper rod through and out of the bump stop. It may take several whacks but she'll eventually come out. I've found this to be the easiest method for difficult-to-remove damper assemblies. Good luck!
  12. Doesn't look like there's very much compression on that motor. Did you check ring end gap after honing your cylinder prior to re-assembly?... or a compression test afterward? Seeing how easily you're able to push through with your kickstarter by hand makes me wonder if there's enough compression for her to fire. Even if she does, I think you'd be so much happier with a new top end anyway. 125cc motors have to work so much harder than those of larger displacements and typically need to be refreshed/rebored with greater frequency as a result - at least that's been my experience, anyway. Keep that OEM piston (in case you stumble across another cylinder to keep as an extra!) and move on to the next overbore. She'll be so much peppier with a new top end! Again - great work on the videos. Very entertaining! Cheers - Christian
  13. The woodruff key should be a nice, snug fit. The tighter (to the shaft), the better. If its loose-fitting or visibly damaged, replace it. It's a cheap part and worth the minimal expense - especially when remounting your flywheel. When they're so loose that they fall out on their own, it's easy to accidentally push it out of it's slot and behind the flywheel when sliding your flywheel over the shaft during the attempt to line up the flywheel slot to the woodruff key. Get a good flashlight to confirm it's in position before tightening everything up. You can totally do most of this work yourself... however, as Lorenzo correctly points out, there are going to be some tasks better left to a professional. One job for certain - rebuilding your crank if your crank bearing is shot. Pressing out a crank pin requires a press, fittings and experience... and balancing afterward is something of an art (well, mostly science) that I'd never attempt personally. Beyond that, motor disassembly and reassembly is definitely within reach. You'll learn quickly enough... and, if something goes wrong with your rebuild... just tear it down again and rebuild it till you get it right. Please don't hesitate to reach out if/when you run into any snags. Some wonderful, very knowledgeable folks frequenting this site can help steer you right. Good luck!
  14. Nice bike you've got there! Sorry she seized up on you so early in your ownership... but, on the upside, you are becoming quickly familiar with all you'll need to keep her running happily for many good times in the years to come. Not knowing how far you're planning to tear down your motor, definitely pull that flywheel if you haven't already. I suspect that your incident may have possibly sheared (shorn?)... buggered your woodruff key. All those rpms with a sudden stop at the end might've caused the flywheel to spin over the key on the shaft if the key was not in good condition to begin with or missing entirely. All the more likely given the retaining nut had spun entirely off the shaft. At the very least, the timing will be off if the key was intentionally removed (...for timing purposes? Who knows!) by the previous owner. Also, it may be possible to remove shavings that have fallen into your case by entirely filling the crank area with some pre-mix and carefully working the crank to dislodge any debris from beneath the crank and bearings. Most of that stuff will come loose and can be drained off and blown out with compressed air after a few treatments. Learned that from an old article Rick Sieman (superhunky.com) wrote for Dirt Bike Magazine many years ago. Good luck with your work. I'm sure she'll be even better than before once you get things all back together! PS I loved your videos. Nicely done! Christian
  15. Hi Mickey, OK... I must've blinked. I could've sworn you just got that bike... and you're already further along with your restoration than I, after several months (maybe a year?... I hope not!), with mine! Looks beautiful! Question... have you internally sealed your tank? If not, definitely do so. And don't cheap out when you do. I moved along an m85 Alpina a little over a year ago that had nearly perfect original tank paint. It hadn't been sealed and, immediately after the first pour (despite knowing better, I might add), it sprang a couple of leaks. So I picked up some Caswell Tank Sealer, applied half the sealant - thinking I could split the contents to coat two different tanks. Long story short... I somehow missed one of the leak points in my application... and you can guess the rest. Won't be making that mistake again moving forward! So definitely protect that beautiful paint if you already haven't! Keep up the great work. Looking forward to seeing her when you're finished - which, at your rate, should be pretty darn quick! Cheers - Christian
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