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ericbenjaminjr

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Posts posted by ericbenjaminjr

  1. I have a pair of trialtech sport cranks and just discovered the pedal thread on the right drive side crank is offset. Each crank has at least 9mm material around the threads but this one has only 7mm at its weakest point. I'm wondering if this is something I shouldn't ride or if it is within tolerances. I wont rant about my favorite manufacturer because I have the feeling the shop I got it from purposely orders B stock and sells it at full price. Because it wouldn't be the first time I've gotten anomalis products from them..

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  2. Thanks everyone for all the input. I've had a chance to do some measurements of my own now that I got a set of new cranks. From that I wouldn't go over 3.5mm maybe 4mm if need be. I don't understand why there are so many 5mm rings out there. I mean almost half the rings in some shops are 5mm. I wouldn't want to leave so little thread left over now that I've seen with my own eyes.

    So next I'll be porting all the designs to solid edge and doing some virtual stress tests. Any suggestions on how I could economically go about getting CNC one offs done would be much appreciated.

  3. I've done a bit more research and asked around a bit. It seems 5mm is ok but not optimal for all setups. So I'm going to wait and try out my original JafBikes ring until I bend it and analyze the damage.

    In the meantime I worked on one of my own designs. I couldn't help myself but to be inspired by the Jaf ring though. I took a guess on completing the circle of the ring hoping it would provide some stiffness. This is my first draft. I call it the knucklering.

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  4. Oxymoron init?

    Indeed! I'm also looking into double wall rims but theres not much to compare there. I have an excel chart comparing weight and prices. Ironically, the trialtech single and double walls are just 77g difference. The bonz are 177g lighter than trialtech double wall. So far doubles are winning.

    Go for the Trialtechs

    I've heard allot of good things about the trialtech single walls. I forgot to mention rockman rims which I hear are just as good?

    So far what ever I do will be better lighter than my super heavy echo TRs with 2mm spokes and brass nipples.

  5. I'm looking to build up a set of new wheels and wanted to ask around about your best experiences with single walls. I've already decided on trialtech sport lite hubs. The rear has a nice wide flange for good stiffness. As of now I'm contemplating bonz or trialtech trims. I know they're not going to be as strong as double walls but whats the best I can do with singles?

  6. i always think 5mm clamp section is always overkill on bashrings. I always ran 3mm, and had no issues.

    I'd rarther destroy a bashring, then strip the threads on a crank due to their not being enough thread engagement.

    Yeah, I had an echo urban I think it was. Didn't fancy using it on my zhi cranks, worked well on my tryall though. Guess it depends on the cranks you ride.

    Thanks for the info guys. I'll check into it a bit more.

  7. I finally got some time to finish up the remake. I decided on keeping the design as close as possible with the few minor changes. I made the diameter 91.1mm to prevent the chain being hit between the cutouts around the outer rim. The large cutouts are a bit larger and all the same shape. I did a bit of research and I'm thinking making the entire ring 5mm thick will be enough to prevent bending. I'm just wondering how much lighter it would be with 7075 alu or if at all due to the thickness.

    I also got my Jaf ring from TartyBikes. Its 3mm thick and just by looking at it I know I'll bend it sooner or later. So I'll be moving on to some of my own designs now.

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  8. i'd agree that bending isn't good, but snapping a bashplate isn't good either; alu is likely to bend but if it does it's usually likely to die soon after. bending back the ring wasn't a problem either (Y)

    the impact that bent it was a bit of a wierd scenario, i don't imagine any bash ring would have faired very well in the incident.

    I understand. I guess you're right. I've never run a bash ring that wasnt tapered.

    I've been reading up on the properties of 7075 aluminum and it seems to be the perfect choice for this bash ring. It has the lightness of aluminum and hardness of steel.

    I'm no physics expert but I imagined the JAF ring as a straight bar with all its waves and cutouts and imagined twisting it would be fairly easy. Thats how I came up with closing the inner ring, thinking it would stiffen up the structure as a whole. I need to research how I could get one off prototypes done cheaply. Maybe I would take this a bit further...

    That bike is bad ass BTW @Trials Bummer!!!

    • Like 1
  9. Will the new taper clear the crank?

    What material are you thinking of using?

    Yeah it tapers to the inside towards the freewheel. The crank side is flat. I'm thinking of 7075 aluminum. So far this is all theory. Fun and games with the option to get serious if I come up with something really good.

  10. Well bending isn't good. Never had a bash ring bend on me. Not really something I'd like to start accepting as normal. I made a few changes to prevent bending, and a few minor design changes as well. This is of course no long a steel design.

    1. Made it taper to 5mm thicker.

    2. Removed some holes.

    3. Left the ring around the crank intact. You still wont see it when the crank is on.

    Did I break it?

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  11. it explodes

    LOL, the plutonium version was out of stock..

    I added a generic crank and freewheel to the template so I can better see what the end result would look like. Also started drawing up a few ideas of my own on paper. Actually came up with a few. But I'm still very interested in whats wrong with the JAF ring. I really love the design and maybe I can improve on it..

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  12. Yeah you're right, the original has two sections without any holes at all. But like I said, this was only a workflow test. I needed a subject right away. This workflow is for an 8 section design. Jaff was a great subject because of the complexity. I'll be making a few more workflows before I start to get creative myself..

  13. I was just working on a workflow for creating bash rings. I just ordered one from JAF Bikes. I'm so in love with this thing, just wish I could get it in anodized black 7075 aluminum. I decided to use his design to test my workflow. What do you think?

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  14. I've been riding trials since 2004 and this has never happened to me before. I was pedal hopping a wall at a spot I regularly ride and I suddenly lost all coordination. All the subtle nuances like timing, calculating distance and pedal position just got all jumbled in my head. The first time in my life I've ever hit the brakes and aborted my approach. I laughed and did it again, and again and again. You know how it feels when you blackout and cant remember someones name? Thats how it felt, like I forgot how to do it! Its a routine move. The wall gets higher from left to right and I regularly practice there to get more height. I know all about how some rides just suck but this was different. I left the spot and hopped another straight wall about a half hour later and everything was back to normal.

    Anything like this ever happen to anyone before?

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