Viewing 38 posts - 161 through 198 (of 198 total)
  • I've broken 4 frames in 13 months. Recommend me a 29er hardtail.
  • Terry
    Free Member

    Well I know him personal, so it wasn’t that difficult for me to choose.

    Everyone needs steel.

    jameso
    Full Member

    Ah ok, I hadn’t heard of them until a ride with a bike shop where his brother worked (ben-ben in copenhhagen). Nice guys, nice bikes. The local guide for the day also had an Ari.

    Chainline
    Free Member

    Graham, just looking at 29er pic thread and saw you in Vegancyclist get up, kept meaning to say hi at various 24s we seem to have done together but I didnt know what you looked like..turns out we’ve chatted regularly on course but I did not know it was you!!

    Have you decided what to go for yet? Nicolai, Chumba??

    I am talking to Nicolai about a lightened AC29er at the moment but you were lookng at the Argon I guess?

    Anyway, I’ll know next time to say Hi properly 🙂

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    john_l
    Free Member

    Sorry to resurrect an old thread, especially this one ;0)

    My Ridgeline 29SL has just gone in exactly the same place as the OP. 2010 model.

    druidh
    Free Member

    Standard question – when the seatpost is in place, does it extend past the bottom of the seat tube / top tube join?

    Does the 29SL use a shim in the seat tube?

    john_l
    Free Member

    Standard answers…..

    Yes
    No

    :o)

    michaelmcc
    Free Member

    Try losing some weight lol….

    john_l
    Free Member

    oh yeah, 10.5 stone!

    bigdugsbaws
    Free Member

    Does the 29SL use a shim in the seat tube?

    It does

    druidh
    Free Member

    Thanks Doug. Do you know far down the shim is inserted? With a proper length shim and a seatpost in there, you’d think there would be little stress on the actual frame.

    bigdugsbaws
    Free Member

    Its quite short Colin, just measured mine and there is only 85mm in the frame. Mine is a 2011 so its shimmed to 27.2mm, the 2010 frames were 31.6mm. Think the wider/stiffer posts of the earlier frames are contributing to the failures.

    bobster
    Free Member

    Looks familiar.

    Had the same happen with my Hummer.

    Just can’t see a connection between your Ridgeline and my Hummer that wasn’t built by Litespeed though…. 😛

    Only just realised I’ve got some replies on this thread.
    John, you’re about 2/3 my weight, so it does look like there was a design fault with Lynskey, it’s not just me overloading it.
    I’ve done about another 4000km on my Ridgeline since the repair with no further problem.

    It seems strange to me that Lynskey have kept quiet about this. They’ve obviously built up a reputation for frames that crack, although they appear to have got it sorted now.
    I’d have thought it would be better to admit there was a fault with the design, they’ve changed it now and will do a free repair on any older frame that cracks, than to hope that no one bases their choice of frame purchase on a reputation that is no longer deserved and lose a sale.

    Where did you buy yours John ? CRC ?
    I don’t know if you’ve followed the whole story, but CRC weren’t much help at all, taking 5 days to reply to emails and ignoring my request for a free seat post.
    Avoid Jack at Lynskey, he’s got the worst customer relations attitude I’ve ever seen.
    Don was OK. He got it sorted and arranged for CRC to include a new Thomson 27.2mm seat post FoC when they returned the frame, so it’s probably worth contacting him to see if he’ll do the same for you.

    Anyway, back to the original topic, I’ve ordered this in my attempt to win the Most Niche Bike on STW award.

    In case you can’t make it out on the drawing, that’s a titanium 29er with Rohloff drop out and cable guides, split seat stay for a belt drive and Lefty head tube.

    BadlyWiredDog
    Full Member

    It seems strange to me that Lynskey have kept quiet about this.

    Maybe they’re just relying on you to do it for them? 😉

    macb
    Free Member

    Interesting thread, I’m the same size as you, heavier and have a similar riding style…offroad roadie if you like. Looking at the pictures you’ve posted and scanning the Lynskey site, I have a couple of questions:-

    the alloy frame that you had repaired, that looked to have a fairly lengthy ST extension above TT without support. Any chance of extension length and overall ST length on this one?

    the Lynskey frames – your original, and repaired frame, seem to have different above TT extensions. The extensions also both seem to be longer than the latest version of the Ridgeline 29SL. Though I’m only going by the piccie on the Lynskey site here.

    Regardless, the ST on the Lynskey does seem rather short, 470mm CtoTop. According to my calcs that would only give me about 126mm of a 410mm Thomson seatpost in the frame. I’m also not so sure about shims and butting on the ST.

    Looking at the geometry of other similar hardtails Lynskey do seem to be particularly short. Niners are all 12/13mm longer at your size range and the likes of Singular/Salsa/Surly are all 500mm+. If you go up a size then you get to the 530-550mm range.

    I know that the min insertion is covered but I’d be looking for a straight gauge ST, at least 500mm and either minimal above TT extension or gussetted. Obviously the former will increase the standover but how important is that to you? I have no issues at 850mm on standover and don’t see the need to push any boundaries to get the 800mm Lysnkey offer.

    If they want to make a big bike as small as possible then they have to beef up the right bits. I would have been surprised to see the same sort of failure on a Surly, Swift or the Salsa steel or Ti.

    IanW
    Free Member

    Have to say titanium is looking like a pretty poor frame material, stories of them breaking seem quite frequent.

    Nothing exceptional about the Op’s weight or mileage (if there is Im in trouble!) more like duff bikes.

    boxelder
    Full Member

    I snapped an 853 kona explosif there using a shimmed post in the extended seat tube.

    pushbikerider
    Free Member

    Hi Graham – that looks like an XACD drawing, I’d be interesting in seeing how it turns out and doing a bit of a write up for my blog http://www.spanner.org.uk let us know how it goes…

    macb, I like the phrase “offroad roadie”, I wonder if it will become the next niche market. 😀

    The seat tube on the White Gary Fisher Rig is 450mm (BB centre to top) with 85mm above the centre line of the top tube.

    The seat tube on the repaired Lynskey is 475mm, about 5mm longer than standard for a large frame.
    The repair appears to be a 95mm length of thicker walled tube spigoted in to the existing seat tube, so, as far as stressing the frame goes, there would be no advantage to having more than 95mm of seat post in the frame.
    I *think* the new frames have got a built in shim, rather than being thicker walled tube. I don’t know how long the shim is.
    If, say, the shim is 100mm, then there is no point having more than 100mm of seat post in the frame. The excess will simply poke down in to the open space below.

    The Qoroz I’ve ordered has a 508mm seat tube (BB centre to ST top) with only 45mm from TT centre to ST top, so I’ve lost a bit of standover height, not that it bothers me if it means the frame is stronger.
    I mentioned my frame breaking history to Chris at Qoroz and suggested they add a gusset at the ST/TT junction with an extended ST. He was confident that even with the thinner walled ST for a 31.6mm seat post, I wouldn’t break it.
    He did add a brace between the left hand seat stay and chain stay at my request though to handle the torque reaction of the Rohloff hub.

    pushbikerider, I thought the drawing style looked familiar too, although I wondered if it’s just because everyone uses the same CAD software.
    I know I probably could have saved a fair bit by cutting out the middle man, but I wanted the reassurance of dealing with a UK “manufacturer” in case I ever have to make a claim on the lifetime warranty.

    macb
    Free Member

    Hmmm, I can see how there would be little point in having a seatpost extending down past a shim. But would it have no impact? I don’t have the engineering to answer that but I was thinking that a deeper insertion would be marginally better unless it allowed seatpost movement.

    The Qoroz looks good and if the builder is prepared to stand by the design then I’d be happy. If you have 508mm of ST then you’re looking at closer to 50% of the post inserted rather than the nearer 25% mark of the Lynskey, that’s a huge difference.

    I hadn’t realised the GF Rig you broke had such a small seat tube. I know others are saying Ti breaks a lot etc but that’s not the impression I have. There are a lot of repeat postings of the same frame breakage and there’s a lot of unsubstantiated opinion. Most of the problems I’ve been able to find, Ti or otherwise, seem to share similar attributes:-

    quality control – a known or recognised poor batch or builder

    really short seat tubes – being of the larger persuasion I’m happier with at least 150mm of a 410mm post in the frame, preferably more. The 100mm min insertion is a seatpost limit it isn’t a frame limit.

    long seat tube extensions above the TT without additional support – this makes me nervous, though I have no technical support for that feeling, it just looks vulnerable. By long I’m thinking anything over about 40mm. I do seem to remember reading something about that being a recommended limitation from XCAD.

    shimming, butting and manipulation – a lot of this looks like workarounds to me. Trying to get a given framesize to cover a broader range of rider sizes. Almost as if they start with aiming for clearances around the shortest/smallest recommended rider rather than the midsize in the range. This would put the riders at the upper limit of the size range at the extremes of the design.

    rider/user error – treating an XC frame as a freeride or similar, crash damage not being investigated properly and otherwise exceeding design parameters.

    I hope you post up plenty of pics of the new frame, looks like it’ll be great.

    One more thing that may be relevant, I’ve been told that there is a very limited range of titanium tubes available to make bike frames from.
    Whereas aluminium can be tapered, butted and hydroformed to almost any shape the frame builder wants, all the titanium frame builders are working with essentially the same tubes.
    I don’t know how true that is, but apart from a few variations like Lynskey’s twisted helix frames and the squared top tube and down tube on the Ridgeline, there does seem to be a lot less variety of Ti than Alu frames available.

    macb
    Free Member

    That would be my understanding as well, it’s not like there’s a ti smelting plant and mill in every town.

    I was looking further at the Lynskey geometry for the Ridgeline-29 SL. They have the Large as covering 5’11” to 6’2″ and the XL as 6’3″ to 6’6″. I know that you can size up or down to suit but you’ve got a 1″ gap there. Running down the list the only big difference is in the ST, it jumps from 470mm to 520mm. Yet the ETT only jumps by 12mm, part of which is acounted for by a half degree increase in HT angle, and the HT jumps by 6mm. Everything else stays the same.

    The 7″ height range from 5/11 to 6/6 is quite a jump to be covered by such minor changes.

    pushbikerider
    Free Member

    Ahh; Qoroz have their frames made by XACD hence the confusion – I can see why you’d want to keep things local given your current luck with frames!
    Definitely interested in seeing how it turns out 🙂

    rootes1
    Full Member

    Have to say titanium is looking like a pretty poor frame material, stories of them breaking seem quite frequent.

    more likely incorrect use of frame material and sizes for the job.

    One more thing that may be relevant, I’ve been told that there is a very limited range of titanium tubes available to make bike frames from.

    again likely to lead the use of tubes etc that are not quite suited to the job

    those cracks are from that whole joint rotating backwards and putting the middle under tension (why the crack is wide in the middle and not the ends – they would be better putting the joint for the seatstays/ST higher up than the ST/TT joint

    and/or sleeving the ST (if external butted tube is not available)

    “…again likely to lead the use of tubes etc that are not quite suited to the job…”

    I don’t know much about the world titanium tube manufacturing industry, but I would have thought bicycle frame builders were their biggest customer, so the tubes would be made for the job.

    Do titanium road bikes have the same reputation for breaking ?
    Do mountain bikes use bigger diameter and/or thicker walled tube ?
    If all bikes use the same tubes, then either road bikes are over engineered or mountain bikes are inevitably going to fail.

    macb
    Free Member

    Graham, looking at your CAD drawing again and noted you’ve gone for 73/71 angles based on a 475 AtoC with 45mm rake. I’m trying to get my head round exactly what this means. I’m considering some squishy forks and it’s all rather confusing. For rigid geo it seems straight forward, 71 HA, 45 rake, 2.2″ tyre = 79mm trail.

    But I’ve been looking at geometry charts, thinking Salsa and Niner here, that show the numbers for frames based on 80mm or 100mm geometry. For 80mm they’re using approx a 470mm AtoC, 72 HA and 45 rake, which brings up a trail number around the 72mm mark. For 100mm forks they show the angles slacking by approx 1 degree and that bumps it up to nearer the 80mm trail mark. Is the 475mm AtoC you have on your drawing meant to be reflective of an 80mm or 100mm fork? I seem to get varying answers when looking for AtoC info and level of sag to allow etc.

    I’m musing about trying to design something that would work with 80-120mm forks. I was thinking a tweaked Niner geo starting point would be about right. So 74/72 at 80mm, 73/71 at 100mm and 72/70 at 120mm, if my understanding is correct. This would give me trail numbers of 72mm, 79mm and 86mm, or touring/light trail, XC and trail just by changing the forks. The main tweak being a bigger BB drop so that the BB doesn’t get too high as the forks change. Coupled with moveable dropouts to tighten up the back end as the front lengthens, keeping the wheelbase roughly the same. Beef the frame up enough to cope with 120mm travel.

    rootes1
    Full Member

    I don’t know much about the world titanium tube manufacturing industry, but I would have thought bicycle frame builders were their biggest customer, so the tubes would be made for the job.

    Hiya MTG

    no biggest customer for ti tubes is the aerospace industry – bike industry is just picking up the crumbs/using what is available…

    alu and composites (and steel) is always going to be better for the bike industry due to the flexible of design even in limited runs, alu tubing for its hydroform possibilities and composites for complete flexibility even for short production runs…

    doubt due to the limit Ti tube manufacturers and manipulation options this is going to be the case for Ti

    Si

    Rik
    Free Member

    Surely the amount of seatpost length is irrelevant if your frame has a shim?

    If your seatpost shim is say 100mm long, then as long as you have 100mm of seatpost inserted you will get maximum strength. If you have 150mm inserted then the extra 50mm will extend below the shim and not add any extra strength.

    macb, I really didn’t go in to the geometry in that much depth.
    I told Chris at Qoroz that I liked the handling on my large Lynskey and asked him to copy the geometry.
    I’ll be using a Lefty fork, which is 500mm AtoC, the same as the 100mm Fox F29 I’ve got on the Lynskey, so I’m hoping it all works out OK.
    The only significant difference is the 454mm chainstays. This was dictated by the belt drive as I will be using 50×28 single speed and 50×20 with the Rohloff.

    There’s a very limited choice of sprockets and belt lengths for Centre Track and this was the closest I could get to my two current 32×18 & 32×13 chain & sprocket ratios, both using the same chainstay length. I was lucky that they both use the same front pulley which means less parts to buy and easier swapping between the two.

    Macavity
    Free Member

    Independant Fabrication say:

    Home

    “Shot peening is a cold working process in which the frame is bombarded with small spherical metal balls called shot at a precise angle. Shot act like tiny ball peen hammers and create a uniform dimpled texture on the surface of the frame. This compacts the outer layer of the material.

    The processes of butting and welding titanium tubes to make a bike frame are known to create tensile stresses in the frame material. Tensile stresses make the area in question want to pull itself apart. This is a bad property to impart to a bicycle frame as any minor notch or micro crack in the frame will want to propagate and further compromise the material. The induced tensile stresses are most concentrated in the heat affected zone — the area of the welds. Thus, strength is compromised precisely where you would like it to be greatest.

    Shot peening of a welded titanium joint substantially increases both fatigue strength and fatigue life as compared to the same joint which is not shot peened. Shot peening imparts what is called residual compressive stress which counteracts the residual tensile stress, which is created in the process of cutting, grinding and welding. Typically, fatigue strength of a welded titanium joint after shot peening is double that without shot peening. Fatigue life is enhanced by shot peening to an even greater degree.

    By shot peening the frame after it is welded together, we are able to relieve the stresses in the material providing compressive qualities, which are known to reduce micro cracking and enhance fatigue life. Without stress relieving, each of the tubes will retain tensile stresses which tend to conflict with one another. Stress relieving allows the component tubes of the frame to work together as designed, acting as a unified structure rather than a collection of competing parts.

    The shot peening process work hardens the surface of the tube, while giving it a finely textured surface. These two properties together create an attractive finish that is highly resistant to scratches. If scratched, the scratch is harder to see because the surface is textured. The textured surface glitters in the sun in a manner similar to that of a pearl paint job.

    Some people may confuse shot peening with sand blasting or bead blasting. At IF, we use sand blasting on our steel frames to remove contaminants. We also use it impart a microscopic tooth to the surface of the metal to provide a mechanical bond with the paint. Bead blasting is used for cosmetic purposes to provide a uniform finish to the surface of the metal. Neither sand blasting nor bead blasting improve the mechanical properties of the metal.

    Shot peening is used precisely because it improves the performance characteristics of the finished parts. It is used in the aerospace industry, in high performance cars and motorcycles, and in light weight bicycle stems and bars where light weight and high strength are performance imperatives.

    ——————————————————————————–

    What’s the big deal? Don’t a lot of frame builders shot peen their frames?
    To the best of our knowledge we are the only titanium frame builder using the shot peening process. This process should not be confused with bead blasting, which is used to provide a cosmetic finish to ti bikes. Any company that claims to bead blast over a shot peened finish does not understand shot peening. Any type of finish polishing brushing or bead blasting applied after shot peening negates the benefits of shot peening.

    See http://www.shotpeening.com for more info.

    ——————————————————————————–

    Who does the shot peening of IF frames?
    We do not do the shot peening in house. We use Metal Improvement Company in Wakefield, MA, which specializes in shot peening high performance parts for the aerospace industry. At Metal Improvement our frames are peened along side of parts for the space shuttle and F14 jet engine rotors.

    See http://www.metalimprovement.com for more info.

    ——————————————————————————–

    Why can’t IF do its own shot peening?
    To shot peen properly requires the use of very large, sophisticated, and expensive computer-controlled equipment, and trained personel. Shot Peening really is high-tech stuff, and it’s tough to get right. We decided to leave it to the specialists. In addition, we are confident in the established leadership, reputation, and quality of Metal Improvement.”

    Here it is.
    This is not the final build spec. The biggest omission is the belt drive, I’m still waiting for the belts and pulleys.
    There’s a few other odds and ends I’ll be changing, but nothing major.

    Tom83
    Full Member

    Nice, Graham! I’d love a belt drive frame one day.

    GlitterGary
    Free Member

    From those pics above, it looks like your saddle is at an extreme angle, meaning that when you’re pedalling in the saddle, you are puttling a lot of stress on the post, thus the frame int eh place it has cracked. Just a thought. try flattening the saddle a bit, it might help things?

    GlitterGary
    Free Member

    edit: posts double.

    njee20
    Free Member

    Is that an I9 front wheel? Need a matching rear!

    Yes, I9 on the front, Rohloff on the back.
    Flat blade spokes on the back too. I bought the spokes and rim off a guy who had sold his hub, I wouldn’t normally put aero spokes on a Rohloff hub on a mountain bike. 😀

    I’ll be swapping the seat soon for a Gobi. I’ll do something about the angle then too.

    Bimbler
    Free Member

    Sweet ride. Love it. :jealous:

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