Guest majestyman340 Posted February 28, 2008 Report Share Posted February 28, 2008 There now seem to be several new updated chassis kits available for P65 and twinshock bikes, wonder if anyone knows exactly what is available and the prices being asked? Quote Link to comment Share on other sites More sharing options...
fivemeister Posted February 28, 2008 Report Share Posted February 28, 2008 How long is a piece of string? You can pretty much get what you want these days if your'e pockets are deep enough. There has to be a market for reputable frambuilders to make modern copies of classic frames in the latest lightweight tubing. Anyone fancy commisioning some Ossa MAR frames out of Reynolds 531? I reckon you could lose a LOT of weight there. Quote Link to comment Share on other sites More sharing options...
Guest majestyman340 Posted February 28, 2008 Report Share Posted February 28, 2008 Reason I asked the question is that I have heard there are a few kits being made, that cost a lot less money than others intended for exactly the same bikes..................... Quote Link to comment Share on other sites More sharing options...
michaelmoore Posted February 28, 2008 Report Share Posted February 28, 2008 (edited) There has to be a market for reputable frambuilders to make modern copies of classic frames in the latest lightweight tubing. Anyone fancy commisioning some Ossa MAR frames out of Reynolds 531? I reckon you could lose a LOT of weight there. Size for size, 531 is the same weight as 1018 or 4130. All the steels are equally stiff so if you keep the OD the same and go down in wall thickness you lose stiffness. 531/4130 are stronger and generally have a higher yield point, but that just means that you can crash a little harder before things stay bent. The way you make use of the thinner wall thickness is by going up on the OD as the second moment of area normally goes up faster from the OD increase than it falls off from the reduction in wall thickness. So 531/4130 may pay off on a frame using thin gauge tubing because it will add some dent resistance for those times when you throw the bike into the rocks. Also, if the frame is depending on the strength of the tubing to not fail or bend far enough to stay bent (because it was designed so the tubes are loaded in bending instead of compression/tension) then it may benefit from a stronger steel. There's probably a small market. As soon as you start looking into liability insurance for the builder the number of people likely to build things for that market probably diminshes pretty quickly. I noticed a different thread here about (I think UK) events that don't let people inspect the sections before riding, and someone in that made a pretty good explanation of the reasons why you can't ignore liability in this modern world. It is a shame that people get put into the situation of saying "sounds like fun, but it isn't prudent to go there" but that's life as we know it. FYI Morely's "Spanish Trials Bikes" has photos of a Bob Gollner frame for the MAR that was done "in the period." Majestyman, different prices probably are due to different production costs and different profit goals. Someone who wants to make a couple of frames for fun in their spare time and is willing to work for pennies an hour can charge less than someone else who plans on building a batch of 10 with all the fittings and spares and then tries to sell them and make a reasonable return on their investment. Make a small fortune by starting with a big one and then go racing (or building stuff for racers). cheers, Michael Edited February 28, 2008 by MichaelMoore Quote Link to comment Share on other sites More sharing options...
Guest majestyman340 Posted February 29, 2008 Report Share Posted February 29, 2008 Size for size, 531 is the same weight as 1018 or 4130. All the steels are equally stiff so if you keep the OD the same and go down in wall thickness you lose stiffness. 531/4130 are stronger and generally have a higher yield point, but that just means that you can crash a little harder before things stay bent. The way you make use of the thinner wall thickness is by going up on the OD as the second moment of area normally goes up faster from the OD increase than it falls off from the reduction in wall thickness.So 531/4130 may pay off on a frame using thin gauge tubing because it will add some dent resistance for those times when you throw the bike into the rocks. Also, if the frame is depending on the strength of the tubing to not fail or bend far enough to stay bent (because it was designed so the tubes are loaded in bending instead of compression/tension) then it may benefit from a stronger steel. There's probably a small market. As soon as you start looking into liability insurance for the builder the number of people likely to build things for that market probably diminshes pretty quickly. I noticed a different thread here about (I think UK) events that don't let people inspect the sections before riding, and someone in that made a pretty good explanation of the reasons why you can't ignore liability in this modern world. It is a shame that people get put into the situation of saying "sounds like fun, but it isn't prudent to go there" but that's life as we know it. FYI Morely's "Spanish Trials Bikes" has photos of a Bob Gollner frame for the MAR that was done "in the period." Majestyman, different prices probably are due to different production costs and different profit goals. Someone who wants to make a couple of frames for fun in their spare time and is willing to work for pennies an hour can charge less than someone else who plans on building a batch of 10 with all the fittings and spares and then tries to sell them and make a reasonable return on their investment. Make a small fortune by starting with a big one and then go racing (or building stuff for racers). cheers, Michael Just heard of a Majesty Yam chassis available from a builder in the UK Midlands for Quote Link to comment Share on other sites More sharing options...
michaelmoore Posted February 29, 2008 Report Share Posted February 29, 2008 Issue 5 of "Classic Dirt Bike" has an article on a person named Craig Malwem who is making new Majesty kits. Perhaps that is who you are thinking of? But it sounds like Quote Link to comment Share on other sites More sharing options...
scottt Posted February 29, 2008 Report Share Posted February 29, 2008 Issue 5 of "Classic Dirt Bike" has an article on a person named Craig Malwem who is making new Majesty kits. He also does the Mini Majesty frame for Quote Link to comment Share on other sites More sharing options...
woody Posted March 1, 2008 Report Share Posted March 1, 2008 Just out of interest, as I don't want one, who is it that you have heard is making Majesty frames for Quote Link to comment Share on other sites More sharing options...
feetupfun Posted March 1, 2008 Report Share Posted March 1, 2008 (edited) Maybe the 600 UK pound Majesty frames are someone modifying TY250 frames to be replicas of the first model Majesty? I have wondered for a while why no-one is doing this as a business as there are so many TY250 frames around. If someone was making new Majesty replica frames and selling them for 600 UK pounds, they would be losing money on each one. Edited March 1, 2008 by feetupfun Quote Link to comment Share on other sites More sharing options...
feetupfun Posted March 1, 2008 Report Share Posted March 1, 2008 How long is a piece of string? You can pretty much get what you want these days if your'e pockets are deep enough. There has to be a market for reputable frambuilders to make modern copies of classic frames in the latest lightweight tubing. Anyone fancy commisioning some Ossa MAR frames out of Reynolds 531? I reckon you could lose a LOT of weight there. Further to the posting by MichaelMoore regarding the use of Reynolds 531 to make replica frames, I seem to remember reading that the standard OSSA MAR frame is made of chrome moly tubing. Whatever it is, it seems to work just fine to me. Quote Link to comment Share on other sites More sharing options...
michaelmoore Posted March 1, 2008 Report Share Posted March 1, 2008 531 is a manganese-molybdenum steel, T45 is a manganese steel, and 4130 is a chrome-molybdenum steel (those are the major important alloying elements as most have carbon, silicon, phosphorus, sulfer and maybe traces of nickel, copper and aluminum too). 15 CDV 6 is chrome-moly-vanadium. "Chrome moly" has become one of those generic terms like "aircraft billet aluminum." If it is a real concern you need to press the person making the frames for exactly what was used, and maybe ask to see the certifications he got from his tubing supplier. For practical purposes they have the same mass/volume and stiffness. Strength and ductility of the tube are the main differences. If you have a tube loaded in bending and you don't want to add more material you may need to go to a stronger steel to keep it from bending permanently in normal use. But identical frames made from 4130, 531 and 1018 have the same stiffness and will deflect the same under identical loads (again, for practical purposes). This is something that is commonly misunderstood, and the popular press don't do much to help that when (as one did) they talk about "oh, the new swingarm we had made of 4130 that is an exact duplicate of the OEM mild steel swing arm made such a noticeable difference in handling." It doesn't work that way. Probably what happened is similar to a story I've heard about Erv Kanemoto when he was tuning for Gary Nixon. Nixon came in from practice and complained about poor performance of the rear dampers. Erv told him to go and rest and he'd sort them out before the next practice session. Since Erv didn't have any spares what he did was pull them off, clean and shine them up, and put them back on before sending Nixon out with the "better" ones. Nixon came back in with a second or so off his lap times and commented on how much better the new dampers were than the old ones. Mental tuneups for the rider can pay big dividends. cheers, Michael Quote Link to comment Share on other sites More sharing options...
Guest majestyman340 Posted March 2, 2008 Report Share Posted March 2, 2008 Maybe the 600 UK pound Majesty frames are someone modifying TY250 frames to be replicas of the first model Majesty? I have wondered for a while why no-one is doing this as a business as there are so many TY250 frames around. If someone was making new Majesty replica frames and selling them for 600 UK pounds, they would be losing money on each one. No ground up new chassis......................but maybe not super trick bronze welded, using costly chrom moly tubing? Quote Link to comment Share on other sites More sharing options...
Guest majestyman340 Posted March 2, 2008 Report Share Posted March 2, 2008 531 is a manganese-molybdenum steel, T45 is a manganese steel, and 4130 is a chrome-molybdenum steel (those are the major important alloying elements as most have carbon, silicon, phosphorus, sulfer and maybe traces of nickel, copper and aluminum too). 15 CDV 6 is chrome-moly-vanadium."Chrome moly" has become one of those generic terms like "aircraft billet aluminum." If it is a real concern you need to press the person making the frames for exactly what was used, and maybe ask to see the certifications he got from his tubing supplier. For practical purposes they have the same mass/volume and stiffness. Strength and ductility of the tube are the main differences. If you have a tube loaded in bending and you don't want to add more material you may need to go to a stronger steel to keep it from bending permanently in normal use. But identical frames made from 4130, 531 and 1018 have the same stiffness and will deflect the same under identical loads (again, for practical purposes). This is something that is commonly misunderstood, and the popular press don't do much to help that when (as one did) they talk about "oh, the new swingarm we had made of 4130 that is an exact duplicate of the OEM mild steel swing arm made such a noticeable difference in handling." It doesn't work that way. Probably what happened is similar to a story I've heard about Erv Kanemoto when he was tuning for Gary Nixon. Nixon came in from practice and complained about poor performance of the rear dampers. Erv told him to go and rest and he'd sort them out before the next practice session. Since Erv didn't have any spares what he did was pull them off, clean and shine them up, and put them back on before sending Nixon out with the "better" ones. Nixon came back in with a second or so off his lap times and commented on how much better the new dampers were than the old ones. Mental tuneups for the rider can pay big dividends. cheers, Michael Is there I wonder any real need to use costly high spec tubes to make a trials bike chassis? Not sure but I dont think any of the mass produced bikes over the last 20 years, used anything other than inexpensive mild steel? Quote Link to comment Share on other sites More sharing options...
woody Posted March 2, 2008 Report Share Posted March 2, 2008 Miller's Hi-Boy frames were Reynolds 531, Beamish Suzuki and Whitlock Ossa were as well I think. Not sure where all this replica frame building is going to end - hopefully not like Pre65. Genuine Pre65 bikes are pretty awful to ride, hence the modernisation which has brought some of them up to the level of good twinshock bikes. The thing with twinshocks is that they are good enough as they left the factory to handle the sections in today's classic/twinshock trials. A Bultaco or Ossa in some new lightweight frame, lightweight hubs, modern forks is no longer a Bultaco or Ossa - is it? Sure, on twinshocks, some people will want to tweak head angles or move footrests or rear shock mounts but that is nothing that wasn't being done at the time. The basic production bikes are still plenty good enough though, the aforementioned tweaks are personal preference and any improvement is probably marginal. Are we going to see new lightweight frames to take later aircooled engines that were never housed in an original twinshock, modern forks, lightweight hubs etc. etc. Probably, unless the regs are tightened up. Maybe the twinshock criteria needs to be altered to state 'twinshock at original manufacture prior to 1984' But then what do you do about the exceptions such as RTX, Cotswolds, Cotswold Majesty........ As those bikes already exists they could be allowed in as they aren't what you'd call trick - Cotswold Majesty uses an original Majesty frame with a Chinese copy Honda 200 engine so no problem with that. The intention would be to stop new specials being built. We all know what a twinshock is, they were the bikes we used to ride and were produced by the factories at the time. People ride them because they have an affinity with a particular marque or because they just fancy something different from the modern scene. Personally, I've no interest in having a superlight frame built for my Ossa or Bult, they are what they are. So far people have been sensible with mods on twinshocks but it only needs someone to start producing specials and we will be going down the Pre65 route again. There's already one out there though, so has a precedent already been set and the horse bolted again.... Quote Link to comment Share on other sites More sharing options...
scottt Posted March 2, 2008 Report Share Posted March 2, 2008 So far people have been sensible with mods on twinshocks but it only needs someone to start producing specials and we will be going down the Pre65 route again. There's already one out there though, so has a precedent already been set and the horse bolted again.... All it needs is the ACU to issue a press release imilar to what they have just done for the sidecars: It was reported that at the 2nd round of the ACU Sidecar Championship last Sunday a number of sidecars did not comply to the ACU specification with regard to the nose cone/overall length and the size and height of the seat. With respect to the nose cone/length of the outfit - competitors are to be given until the 4th round on April 6th to comply and the 1st round in 2009 to comply with the seat requirement. The dimensions for an approved sidecar are available from the ACU Trials & Enduro department. Now a simple thing like that except regarding twinshocks modifications will put an end to it before it starts, cant the ACU get there act together and come up with some simple and understandable rules regarding moddifying twinshocks and do it now before it goes the way the Pre 65 sems to have done, if they wait 10yrs then it will be impossible to ever change it back. Quote Link to comment Share on other sites More sharing options...
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