nigel dabster Posted June 18, 2012 Report Share Posted June 18, 2012 While Fi is commonplace not anwhere is it used at our low revs, which is why the 4rt has a 1800 tickover? Quote Link to comment Share on other sites More sharing options...
neo Posted June 18, 2012 Author Report Share Posted June 18, 2012 Now that is interesting information Nigel .... Do you know why exactly? Quote Link to comment Share on other sites More sharing options...
ham2 Posted June 18, 2012 Report Share Posted June 18, 2012 Funny but I don't see FI as a radical alteration ... just better and more consistent tuning. My guess is DFI for Sherco ... there are manufactures that do 2T DFI compact systems now and Sherco did redesign that engine case for no (currently) apparent reason. DFI would require lubrication to the big end bearing .... has anyone split one of those new cases yet and seen anything interesting in the crankcase?.......... Hold on, I think I've missed something here. Are you saying that pre-mix in the FI on an OSSA 2stroke is a no-go? If so; What cools the piston/little end? I don't know much about the OSSAs,do they have main bearings lubed by the gearbox oil like the Gassers? Wayne Quote Link to comment Share on other sites More sharing options...
neo Posted June 18, 2012 Author Report Share Posted June 18, 2012 Are you saying that pre-mix in the FI on an OSSA 2stroke is a no-go?If so; What cools the piston/little end? From what I understand it's spray/jet lubed from the crankcase. I don't know much about the OSSAs,do they have main bearings lubed by the gearbox oil like the Gassers? I don't think OSSA needs to because it's basic FI/pre-mixed (with 2T oil) down into the crankcase as usual. All the best. Neo Quote Link to comment Share on other sites More sharing options...
copemech Posted June 19, 2012 Report Share Posted June 19, 2012 Now that is interesting information Nigel .... Do you know why exactly? Neo, capacitors are similar to a battery in the sense that they will store energy for a bit, yet they bleed down quickly, thus the high rpm requirement to keep things charging at a certail level that will absorb some dips, yet not for long. A battery is much heavier, yet will absorb energy and store it at a much more constant rate. You gotta switch them off at end of ride or they keep things powered untill dead. A cap simply re-boots every start and will float in the desired zone if you keep it charged, then shut off it goes away quickly. It seems to me that this higher rpm of 1800 is not near as noticable on a 2T either, because due to the expansion design, one ony gets the occasional pops from the exhaust as compared to the once per fireing from a 4T. I have not ridden the Ossr, but I would not tend to chug it for too long either without a battery pack installed. The mean voltages and capacitance here may vary, but below a given point, things shut down with no magneto spinning! Direct injection is a hhole different animal as compared to a simple throttle body in the place of a carb. TBH, I am not quite sure just how this works on a 2T motor, as something must make its way to lube the bottom of things here. Doubt it will work on a trials bike, yet I could be wrong. Quote Link to comment Share on other sites More sharing options...
copemech Posted June 20, 2012 Report Share Posted June 20, 2012 (edited) Taken as a point of interist I have never read up on, here is a snippet I found on direct injection 2T 's. Seems this stuff works quite well actually in certain environments(marine and such) yet it requires a lot of things to get it done. Far too cumbersome and complex for trials application. This is expensive hardware. "So the question is, how is a direct-injected 2-stroke engine lubricated? It can’t use a sump system like a 4-stroke because the crankcase is still acting like an air compressor. And you can’t mix the oil with the gas as in a traditional 2-stoke, since the gas never makes it into the crankcase. An E-TEC engine uses an external oil tank that holds about 2 liters of oil – enough for about 40 hours of engine operation. The oil is slowly injected to places like the crank bearings and cylinder wall. Therefore, the oil does mix with the air getting pumped through the crankcase. It gets burned in the combustion process. The amount of oil is so small that it has no noticeable effect on emissions, and it has none of the pass-through problems with oil as in a carbureted 2-stroke. Also note that, by burning the oil, there are advantages. There is no pollution potential when changing the crankcase oil of a 4-stroke engine (e.g. person spills or dumps oil on ground or water), and there is no possibility of forgetting to change the oil and ruining the engine." Even here I take note of the mention of "pass through problem" which is an issue I intent to expound upon more, later. Feel free to read up on the evinrude marine engines if you like. The thing I found stated they are still on a 1% oil injection ratio. Even my weed wacker is at 2% and about to go leaner on synthetic bike oil! Edited June 20, 2012 by copemech Quote Link to comment Share on other sites More sharing options...
tony27 Posted June 20, 2012 Report Share Posted June 20, 2012 Another thing going against direct injection on a 2 stroke is that is has been banned by the FIM, may have changed now that the road racing classes have been altered to eliminate 2 strokes. I seem to remember the Bimota V-due was originally designed to be direct injected but they had too many problems with it & didn't have the money to sort it out Quote Link to comment Share on other sites More sharing options...
neo Posted June 21, 2012 Author Report Share Posted June 21, 2012 All valid and interesting information gents. I guess I can only hope and dream of my Sherco DFI some time before they put me 10ft under Back on track any other Sherco 2013 news and gossip?? All the best. Neo Quote Link to comment Share on other sites More sharing options...
ham2 Posted June 21, 2012 Report Share Posted June 21, 2012 I've often found that this publication is as much use as a waterproof tea-bag ! Is it a 2012 ,is it a 2013? British journalism at it's best...not ! http://www.tmxnews.co.uk/news/columnists-s5/Sherco-present-Cabestany-Rep-i5747 Quote Link to comment Share on other sites More sharing options...
neo Posted June 21, 2012 Author Report Share Posted June 21, 2012 Good find Ham, Quote Link to comment Share on other sites More sharing options...
stroupdog Posted June 21, 2012 Report Share Posted June 21, 2012 I guess we'll be seing the lanyard style kill switch on all trials bikes in the future? Good idea I think. Quote Link to comment Share on other sites More sharing options...
copemech Posted June 22, 2012 Report Share Posted June 22, 2012 I've often found that this publication is as much use as a waterproof tea-bag ! Is it a 2012 ,is it a 2013? British journalism at it's best...not ! http://www.tmxnews.c...stany-Rep-i5747 This is what I was referring to earlier. Glad you cought up! Now typically this will be a mid year '12 bike production and a glimpse at what may be on the new product line. Fine bike, yet little here to improve my riding, I am afraid. Now, Wayne on the other hand, I am sure he may take full advantage and find great comfort hopping about on the rear wheel with those new lower bars! Quote Link to comment Share on other sites More sharing options...
baldilocks Posted July 24, 2012 Report Share Posted July 24, 2012 find the answer out on Friday when 2013 model is launched. Quote Link to comment Share on other sites More sharing options...
jtrials31 Posted July 25, 2012 Report Share Posted July 25, 2012 find the answer out on Friday when 2013 model is launched. You know for sure it is launched on Fri.? Quote Link to comment Share on other sites More sharing options...
baldilocks Posted July 26, 2012 Report Share Posted July 26, 2012 sherco say so on another site launched at uk world round. Quote Link to comment Share on other sites More sharing options...
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