thanks K ur allrite i dont care what anybuddy else says looks like a normal cam but they got rid of the chain ,guides and oil pump too it looks like fewer parts is always better
Yes I like the design, small motor, very simple and compact. Its never going to be a big HP motor but would do well for many trail bikes etc I believe. I have to wonder how you get the cylinder on and off as obviously you would need to disconnect the valves when you do.
[quote="Motosportz, post: 388210, member: 3. I have to wonder how you get the cylinder on and off as obviously you would need to disconnect the valves when you do.[/quote] im sure the end of the valve stem just sits on the rockerarm pull the jug and u get the valve the spring, retainers and keepers all in 1 chunk i like it i like it alot lol
I have trouble with that design. The automotive world abandoned side valve style engines many moons ago, and now everything (well, nearly everything) is pent-roof chambers with overhead valve (and usually overhead cams). I guess they work for tractor engines (which are super reliable), but I worry about that tech in a bike. There are lots of downsides, which are probably not worth the slight improvement in packaging and simplicity. Kelly, I don't think the disassembly would be any worse than a regular OHC engine, where you have to disconnect the timing chain, and all that bullcrap. Still not saying I like the idea though! I like this merger! I think these brands both show some promise, so some more engineering and sourcing power could help ideas come to fruition.
Would definitely be easy to pull the top end on that thing. Valves all contained in the head, no chain to pull off... Cool idea on old technology but like Kelly says, not going to be a big HP engine.
It is designed for trials for which it seems it would work great. Almost 2 stroke small and light but 4 stroke power. I like it for what it is.
im not so sure on that guys i just googled hot rod briggs 50HP from 34 cid and that was 12 years ago NHRA jr dragsters and kart racers have done a lot of R&D
Cams in the cases. Rockers, working directly on the valves / the intermediary bucket / tappet. It's quite a modern design. And I know that that does seem a strange use of that word - modern. Somewhere, I've better pictures of the design - If I can find it, I'll put it up. My personal experience with side valve engines, having grown up playing on my dads and uncles race shop / garage floor, was down to going "what the hell is this ridiculous thing", as probably a 10 year old, that thought push rod OHV engines were laughable things. Yup, my dad and uncle, thought I was a little 'heathen', in my already well formed reverence for OHC 4ts, that I encountered with their Japanese and Italian race bikes. Though, they also loved / raced 2ts, as I did. Now, I love to see anything different. I have no allegiance to sidevalvers. People often get upset when I profess my desire to see an ultra minimalist, Push rod BIG capacity 4t dirt bike. And, an open to any capacity / stroke type, premier class. Just single cylinder, naturally aspirated engines, would be the limitation I'd put on things, If I Were King................ Yes, a sidevalver would be very suitable for a lower revved Trials application. Mind you, have a listen to a trials event sometime, and especially have a listen to Bou's and Fujigas' Hondas in World Trials. But, bikes like the "no real class" 310 Husky, and now the superb 300 Shercos ( and, of course, the 350 KTMs), show there is a market for bikes of difference. An ultra modern ( to repeat : yes, that's a rather strange tag to apply to a side valver!) ultra low top end height, mid capacity side valve 4t, could give you a good performing , sub 400cc 4t ( or, perhaps, it would be perfect for use in my BIG / Minimalistic 4ts I dream of), might perhaps garner a useful niche for a company that was brave. I truly doubt it will ever happen, but I'm for variety, and less cookie cutter bikes. And, I'm not proposing it's use in an MXer ( other than a bloody big cc'd one), for those that will get all in a tiz about me suggesting something different.
Looks like springs and valves go with the head and rockers stay with the cam/bottom end. Problem is that the valves are shrouded and the mixture has to make a couple abrupt turns into the actual combustion chamber, and then out. So it will never be a real powerhouse in that respect. Think of this, if you break a valve/spring, etc, the piston likely wont shoot it through the head . Also just looking at it and comparing valve to piston size, it is going to be very low power. Then again, if they were to add a turbo charger that would likely fix the airflow problems into the head with BOOST! I vote it gets shell bearings, high oil pump pressure, no counter balancer, and a turbo! Hell yea! Maybe hydraulic roller lifters instead of rockers? Then you would have no valve adjustments!
There are also very big problems with compression ratio on a side valve engine, and that comes with big tradeoffs of fuel efficiency (and emissions). I don't think that a side valve engine is a good comparison to the 310/300/350 class bikes. The reason they are able to make these bikes work (and even the 250 class stuff) is because the OHC engines can rev and breathe well, so they can build a smaller engine that still makes really good power and will be competitive with the 450 class bikes. A side valve 300-350 would make significantly less power, and I suspect would be MUCH less popular than the 310/350 bikes. There is no reason that an OHC engine needs to be unreliable. OHC race engines require top end maintenance because they are race engines, not because they are OHC. There is no reason to believe that a side valve engine would be more reliable if pushed to a similar level of performance (which they can't reach), or that a robust OHC engine can't be set up to be very reliable (at the expense of performance). Look at all the small 4-cylinder cars, which regularly go to 200,000 miles without any top end work. Edit: Turbochargers generally don't significantly improve airflow into an engine; in fact, in some cases they make it worse (look at VE plots for NA and turbocharged engines). A turbocharger doesn't just pressurize the intake tract, it pressurizes the entire engine flow system, including the exhaust side. So, the engine's flow dynamics are operating effectively the same as they were when the engine was naturally aspirated, except for the benefit of increased density due to the pressure increase. The power benefit is due to the density improvement, not improved breathing.
All things considered, wouldn't the X-lite engine be a dream to continue with? Maybe one small application of 250 and 300cc, and one big of 400 and 500 (or 350 and 450)? It's so small, compact and narrow.
thats the problem if it got much bigger on the inside [350 an up] it would start gettin bigger on the outside
I bet GG got burned bad on 4-t engine development and guess they would steer clear from their own engine development and buy instead. Weren't enduro and trials manufacturers scared of all 2-t's being banned for a while? Honda lobbyists sure lost that round, hopefully forever. The side-valve being GG's attempt at a solution. I think there was a youtube clip of the side-valve in a trials chassis and it sounded, well, not too racy.
How about a crankcase supercharged side valve 4 stroke ? (A 2 stroke with valves) With all the work done recently on DI 2 strokes I'm sure that lower end oiling wouldn't be a problem - and wouldn't need premix.
Having valves doesn't make a 2-stroke into a 4-stroke (ie, a 2-stroke can have valves and still be a 2-stroke). The last thing I want to add to my 2-strokes is forced induction and valves. I like them precisely because they don't have all of that junk!
