nigel dabster Posted December 9, 2014 Report Share Posted December 9, 2014 Not answering questions again but just turning them round? you think jeff smiths bsa (when did they fold?) scrambler has a direct relation to 2015 trials? Glad to get your feelings on DL great insight. The fact that my feelings are the opposite, having seen him up close in the wtc quite a few times, are the opposite, ie when under pressure be it either injury or adversity is when hes performed best. It should be also noted you have failed to address the questions above, ie why do YOU think efi is not an advantage and why do you know more than vertigo? Quote Link to comment Share on other sites More sharing options...
nigel dabster Posted December 9, 2014 Report Share Posted December 9, 2014 To repeat ossa fajardo WTC series definately as powerful as ragas gas gas, demonstrated by climbing ability. look up the year if you want. Quote Link to comment Share on other sites More sharing options...
trialsrfun Posted December 9, 2014 Report Share Posted December 9, 2014 (edited) Does EFI (electronic fuel injection) give more power or is it another means of achieving the same as a carburettor but possibly more easily achieving future emission requirements. On a two stroke motor cycle is the fuel injected into the combustion chamber, into the inlet or into the crankcases, with pre mix the bottom end bearings still need lubrication. How do the systems work that are fitted to the OSSA & 4RT, I am aware that the 4RT is a four stroke so might differ from that fitted to the OSSA but is a pump required, presumably the vertigo will require a pump to lift the fuel from the low level tank? Edited December 9, 2014 by trialsrfun Quote Link to comment Share on other sites More sharing options...
guys Posted December 9, 2014 Report Share Posted December 9, 2014 Fuel injection always requires a pump. One of the advantages of EFI is you've got the possibility to use different maps as mentioned in the advert from Vertigo. Quote Link to comment Share on other sites More sharing options...
gasgas249uk Posted December 9, 2014 Report Share Posted December 9, 2014 Some top riders dont like fuel injection power delivery. They consider it just to sharp and crisp off the bottom and feeling for grip isnt as easy as with a carb. Where with a carb on initial throttle opening you can really feel the initial fluffiness as the power creeps in , some say the injections bikes are to quick and run away ....just a little bit more. Fuel injections systems on two strokes also suffer from reliability problems after 5 of so years. The injectors milk up as the oil mixes with the water drawn through in the air. Its very difficult to service this without quite a big strip down. The compressors operate under high pressure and seals perish making them fail.This has happened to me numerous times on FI 2 strokes. If my experience with FI bikes is anything to go by , then FI bikes will have a shorter life than carb bikes----that is unless you want to throw money at. £100+ for an injector. £250 for a compressor as opposed to a carb with Zero of these costs. I love progress , but in my opinion FI bikes will not have as long life as a carb bike and will be confined the breakers earlier...because thats whats happening right now with other scooters that run similar systems 1 Quote Link to comment Share on other sites More sharing options...
dixie Posted December 9, 2014 Report Share Posted December 9, 2014 My 2006 4rt has never missed a beat. And the bike isstill worth well over half of its purchase price. And still gets in the awards at club level. Is there even a 2006 gas gas still running?? And if so is it even worth a grand?? So Fi on a 4t seems more than reliable. I drowned mine when it was almost new. I was a bit nervous that it would be ruined. Followed the.normal dry out . and it has never let me down.. Quote Link to comment Share on other sites More sharing options...
baldilocks Posted December 9, 2014 Report Share Posted December 9, 2014 Two guys from the North East do the Ssdt on their 2006 model GG pro's. Ian Rutter and Geoff Fielding. They were on those bikes in 2012 and 2013 and i saw them in some of wetfeets recent photos from a Richmond trial. From an environmental point of view either stop carbs leaking or go FI i don't mind which option is taken. Quote Link to comment Share on other sites More sharing options...
neils on wheels Posted December 9, 2014 Report Share Posted December 9, 2014 Just to clarify the titanium vs steel / CrMo situation. Yes size for size steel and CrMo are stronger and stiffer than Ti, but because Ti has a specific density just over half that of steel / CrMo, for a given weight of frame Ti is far stronger and stiffer. I don't agree. 'Specific density' is meaningless, density is already a specific measure. I suspect you mean specific stiffness, which is derived by Young's Modulus / Density. If you calculate this for common Steel, Titanium and for that matter Aluminium, alloys, you will find all three have a specific modulus of ~ 25 x 10^6 m^2 s^-2 So in your first post you referred to lighter more rigid titanium, it is not. It is less dense and less stiff. In your second post you stated that for a given weight titanium is far stronger and far stiffer, it is not. Specific strength (in tension) of titanium is ~ 10% greater than steel, specific modulus, stiffness to weight ratio if you prefer, is much the same. Since I wasn't in the BSA comp shop fifty years ago, I do not know if they were seeking to optimise weight, strength or stiffness. Titanium would be best for lightness, steel for strength/stiffness. Balancing all three, I.e specific strength and/or stiffness you have to conclude that there would not be much difference and that geometry and working method would possibly have as much influence as material choice. Then there is how the frame 'feels'. Some of us prefer the flex of steel frames (e.g. Gas Gas) compared to the stiffness of aluminium frames (e.g. Beta). The difference in feel in these two frames is much less about the materials chosen than it is about the small section versus large section structures used in frame construction. 1 Quote Link to comment Share on other sites More sharing options...
biffsgasgas Posted December 10, 2014 Report Share Posted December 10, 2014 (edited) I don't agree. 'Specific density' is meaningless, density is already a specific measure. I suspect you mean specific stiffness, which is derived by Young's Modulus / Density. If you calculate this for common Steel, Titanium and for that matter Aluminium, alloys, you will find all three have a specific modulus of ~ 25 x 10^6 m^2 s^-2 So in your first post you referred to lighter more rigid titanium, it is not. It is less dense and less stiff. In your second post you stated that for a given weight titanium is far stronger and far stiffer, it is not. Specific strength (in tension) of titanium is ~ 10% greater than steel, specific modulus, stiffness to weight ratio if you prefer, is much the same. Since I wasn't in the BSA comp shop fifty years ago, I do not know if they were seeking to optimise weight, strength or stiffness. Titanium would be best for lightness, steel for strength/stiffness. Balancing all three, I.e specific strength and/or stiffness you have to conclude that there would not be much difference and that geometry and working method would possibly have as much influence as material choice. Then there is how the frame 'feels'. Some of us prefer the flex of steel frames (e.g. Gas Gas) compared to the stiffness of aluminium frames (e.g. Beta). The difference in feel in these two frames is much less about the materials chosen than it is about the small section versus large section structures used in frame construction. Your right... other than the spelling of optimize... everything is spot on. Well done sir. So lets turn this back to Vertigo. Given that "someone" might drop this bike at some point. Looking at the frame do you think that a simple blunder might compromise its integrity? I don't ask this to challenge but more of a thought that I have been pondering... I have dented my fair share of trials frames. I have even broken a few. I know a thing or two about mechanical stresses but am open minded enough to understand the factors that may have not been considered. One dent in an frame shouldn't be the end of a bike. Club man riders won't ride it much if that was the case. My first rule of trials for a noob is to "let go if things get weird, the bike will be OK". I am interested to see how critical the girder based frame vertigo with damage will hold up. People are going to drop this thing. Smart people designed this thing but it still makes you wonder what were all of the considerations. Dadof2, TI and Steel have much different properties. Stiffness spoken generically does not speak for the forces exerted within a design. If you design a frame using one material does not mean its going to work for all materials. There are too many critical X's in design that have to be considered so no one factor is the answer. Never start your sentences with the word "But" and never ever ever ever not capitalize the sacred Jeff Smith's last name on a forum post about Trials. This takes away from your argument what ever that may be. --Biff Edited December 10, 2014 by biffsgasgas Quote Link to comment Share on other sites More sharing options...
canada280i Posted December 10, 2014 Report Share Posted December 10, 2014 If my experience with FI bikes is anything to go by , then FI bikes will have a shorter life than carb bikes----that is unless you want to throw money at. £100+ for an injector. £250 for a compressor as opposed to a carb with Zero of these costs. The injector part for the ossa is only around $100, I have had 2 ossa's so far without any fuel delivery issues. What part is the "compressor" you refer to, I don't know what that is and can't find a reference to it in the parts diagram Quote Link to comment Share on other sites More sharing options...
baldilocks Posted December 10, 2014 Report Share Posted December 10, 2014 Probably means the fuel pump Quote Link to comment Share on other sites More sharing options...
canada280i Posted December 10, 2014 Report Share Posted December 10, 2014 (edited) Ah! that makes more sense, thanks for the clarification Don't some sherco's also have a fuel pump as well? I though I had read that somewhere Edited December 10, 2014 by canada280i Quote Link to comment Share on other sites More sharing options...
baldilocks Posted December 10, 2014 Report Share Posted December 10, 2014 (edited) Yes they do but it just runs off crankcase pressure its not electronic which i think the ossa and mont are. Not convinced two stroke oil can be such an issue when its mixed at 100 / 1 ? And is £100 really so much if it fails every 5 years ? That's about the price of a braktec master cylinder which a beginner could break every week Edited December 10, 2014 by baldilocks Quote Link to comment Share on other sites More sharing options...
canada280i Posted December 10, 2014 Report Share Posted December 10, 2014 Yes they do but it just runs off crankcase pressure its not electronic which i think the ossa and mont are. Not convinced two stroke oil can be such an issue when its mixed at 100 / 1 ? And is £100 really so much if it fails every 5 years ? That's about the price of a braktec master cylinder which a beginner could break every week I totally agree, I think I have only heard of one fuel pump failure on this forum and the part is a common part across other bikes that can be sourced quite cheaply on the bay Quote Link to comment Share on other sites More sharing options...
trialsrfun Posted December 10, 2014 Report Share Posted December 10, 2014 Fuel for the fire?...http://www.edmondson-racing.co.uk/technical_info.html Quote Link to comment Share on other sites More sharing options...
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