Jump to content


  • Content Count

  • Joined

  • Last visited

About bultacobrian

  • Rank
    New Member
  1. Hey alpthusiast! That's good info to have. @stevem75 , tried Hugh's, tried Mobley's, nothing. Lynn couldn't even think of anybody who might have one. Considering that most of the original exhaust is kinda intact (involuntarily de-restricted... ok, pretty ratty), except for the first couple of bends which don't exist, I'm gonna look into repairing that first. Might the be shortest path to a solution until something better presents itself. And so, as the market dictates, up goes the price of the pipe I need to get rid of. Thanks for the helps fellas! Let me know if y'all stumble across a good used one, or even a half-good used one. -bb
  2. Hi Steve! Thanks for the reply. I've got the manifold so I'm good there. The original was rusted solid. I've also already got a muffler, maybe NOS, or at least cleaned up and painted, which is more than I could ask for. As a learner bike, I'm not so concerned with appearances. So you know Bob, eh? Whereabouts are you located? He's a nice guy, I like chatting with him, and he means well, but he's also an 80+ year old guy who runs his business because he's afraid he will die if he retires. I try to remind myself to frame my experiences there in that context. I could've sworn I called Tim about an exhaust, but maybe not. That might've just been when I was looking for clutch parts. It would make sense because I probably was still operating under the assumption I had a good pipe. I'll give Tim a call and also Lynn again. Thanks for getting me to think about those sources again. I was trying to not have to buy one from Spain. Thanks for clearing up the distinctions a bit. Here's hoping there's still a used one to find! -bb
  3. My bike is a model 165. The pipe that I have might be for a later model 350, not really sure. I wish there was an exhaust reference with all of the pipes shown for the different models, given the Bultaco model naming convention. To further complicate things, we looked at the dealer parts book and there were 3 pipes made for just the one model, depending on which international market it was being sold in. I might drag my bike down to the local dealer and see if he has any scrap parts that we could hack together. Was hoping someone on here knew of a buddy with a 165 in the shed to part out or more info on the repro pipes.
  4. Hey! So, I've got my bike almost buttoned up, but my local guy can't seem to find me the right exhaust, after selling/trading me 3 different pipes. I see a few online sellers with reproductions for sale. Some of their ads show the same pics for a TON of different models. So my question is this: are these guys making one-size-fits-most repros, or are there other model exhausts that will fit my bike? Initially I didn't want to start this project without the pipe. BUT, I trusted my local Bultaco guy and bought one and now here I am, a bunch of money sunk into this and stuck between cutting and hacking together a franken-exhaust, spending a ton of money for a repro, or waiting until one hopefully turns up some day, maybe. Worst part is I saw one sell recently and had I known that I still didn't have the right pipe, I would've snagged it in a heartbeat. A m166 350 pipe looks close enough, could I just modify the opening to fit the right muffler? Local guy says they won't mate up but I'm more optimistic about it, if the pipe bends are right. Any advice on fitting a substitution, sources for this pipe, or cross-references would be greatly appreciated. Thanks in advance! -bb
  5. Nah, it's not aftermarket, definitely stocked, and then modified. Thanks though! The spring in question is a standard looking spring with 2 open hooks on the end. Unfortunately I won't be back in the barn until Friday, but I did find a pic of the brake pedal that I believe was taken before disassembly, but it's from the bottom, so I'll have to stare at that a bit to get it upright. I'm no photographer, but I do have a couple of gems for you folks soon. -bb
  6. Gotcha! OK! For what it's worth, all of the lights and speedo and extra were stripped or non-existent before I got to it, so that makes some sense. I'm a drummer and can appreciate the feel of a return spring on a pedal, but we'll see how it goes, err, stops first! @Model80, you're right! But my phone was too dead to snap pics and I was banking on image searches to bail me out, but here I am. I did find an old pic of the pedal, post-disassembly, but pre-unassembled if that makes sense, and without a spring, and it seems there's another washer I need to scare up for it. Thanks @feetupfun !!
  7. So, I didn't take enough pics when disassembling and I need some verification for my mod 165 Alpina. I believe I have the pivot part sorted out, but there was a spring in the bag of brake parts that I thought was a pedal return spring. There's a hole in the pedal that looks about right for it and it looks like the spring has worn a few grooves into the pedal it self but I don't see where the other end of the spring could attach to anything. Maybe there's a hole in the swingarm bushing or something? Most pics online either have an earlier assembly or are unclear. Some look like they have the hole but no spring. Is there supposed to be a return spring, and if so, where does it attach? Thanks in advance!
  8. Got it! I get the principle of differential expansion and whatnot, I just don't know anything about the design of cylindrical roller bearings so while it's an easy idea to accept it's benefits at face value, I don't actually understand the mechanics as it relates to that type of bearing. BUT, your explanation helps a great deal in understanding the shortcomings of deep groove roller bearings in the application, and anything that makes reassembling cases easier is always a plus. Thank you!! -bb
  9. Hi John, I actually accidentally found that site recently. Haven't sifted through it yet though. Too busy getting ready for vacation! I don't quite follow you in regards to "fling" but I can appreciate anything that makes closing up cases easier. The crank/case gap theory makes a lot of sense though. I dig it. Even gap, even seating, even flow, even load, even wear, etc. That's a neat technique! I have a shop manual I'm working from, and after having worked as a cook for more than a decade, I've little fear of burns. @feetupfun - Unpack that lingo a bit for me? Do you mean, as things heat up, the inner bearing race will move away from "center" and shift towards a looser fit on the crank? And cylindrical roller bearings have enough slack in that direction while still being within operating limits to soak that expansion up? Please correct me as I'm just making this up, trying to visualize what that could mean. Thanks guys! -bb
  10. Thanks for the warm welcome guys! I'm already well acquainted with Bob Hogan after trying to get my piston un-seized (profile pic coming soon) and a round of parts buying. I'll have to try and check out Alex' place next time I'm in the area, or make a 1-2 stop and hit up Hugh's as well. I snagged the rebuild kit from Hugh's and a few odd bits already, but I'd like to checkout the Hugh's store and not hafta pay shipping. Scot, that's exactly what I was shooting for with this bike. Easy to work on, parts availability, versatility, fun, vintage. Thanks for the reassurance! My girlfriend will very quickly want a bike as soon as this one is running, so I'm already thinking ahead like, "Well, maybe I'll give her the 250 and upgrade to a 350." We're working on getting an RV and we want to be able to travel with the bikes, go places we wouldn't normally go, see sights we wouldn't normally see. While I was initially thinking of getting her something newer and 4-stroke with less of a learning curve (maybe streetable just to have the option), I like the idea of sticking within a brand, and not having to maintain 2 completely different bikes on the road. Fewer tools, fewer manuals, fewer headaches. -bb
  11. Hi John! Thanks for the reply. I've already got C3 bearings lined up for the crank, and I've heard about using a roller bearing on one side, but thanks for the part number! I'll see if I can scare one up for less money than all of the other bearings combined. I'm trying to keep variables to a minimum since this is my first rebuild, so I may just skip the cylindrical roller bearing since I already have a suitable-enough ball bearing for the crank. What's the rational for putting it on the timing side? It's seems counter-intuitive to a beginner like me. Is it a leverage thing, where if the drive side tips a little under load, the timing side sees more actual movement? I guess it's prolly prudent to just get the right clearance bearing for the gearbox and forget about it. Cheap insurance/assurance. What's the purpose of test fitting and measuring the case-to-crank gap beforehand? I'm not sure how you would use that measurement for anything. Wouldn't you still just be shooting for an even gap when assembled anyways? -bb
  12. Hey folks! I'm diving in here head first to the land of vintage dirtbikes, trials, and 2-stroke engine repair. I fell in love with the look of Spanish bikes trying to scare up moped parts locally at Hogan's Cycle Shop in Agawam, MA, and here I am a few years later, elbows deep in a complete teardown to revive a seriously seized-and-left-for-dead 1976 Alpina 250 model 165. My theory is if I do the rebuild right off the bat (not like I had a choice with this particular specimen), the internal condition will be a known quantity, I'll have something I can ride longer, and I'll be able to do repairs more easily. It's been very educational so far and I can't wait to hear it fire. Until then, I'll just hafta keep riding in my dreams, literally. Maybe this isn't the best bike for hardcore trials, but I think it'll serve me well as a gateway bike for trials, trails, and beyond. After a bit of messing around on various 2-wheeled machines, my philosophy with dirt bikes is summed up like this: Speed is gravy. And so here I am, cart-in-pieces-and-before-the-horse, naive and ambitious, ready to fail, ready to learn, ready for a new adventure. -bb
  13. Hi! I'm in the middle of my first rebuild, a real basketcase, and I have a question about transmission bearing clearances being mismatched. I ordered CN clearance bearings but one of them arrived as C3, the clutch side 6303 bearing if my memory serves me right. I looked up the clearance ranges and they overlap by a 1/3 but at the extremes there's a 6-fold difference. Is it ok to use this C3 bearing opposite a CN, or will this result in increased uneven wear and poor operation over time? For ~$10 I'm inclined to keep things consistent, but it's another delay in the project and we're talking <30µm here which sounds small at this operating temperature. I would appreciate some insight here if you've got it. Thanks! -bb
  • Create New...