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Vvt would be pretty freaking cool. It would be like bringing a power valve over to the 4 stroke. Only instead of adding low end like a 2 stroke it would add top end. In theory would that mean they could design the motor around having more lower end torque and then the vvt would open up the top end so you get broad power? Or would it just be used like on my old acura rsx type s to just put everything up top but it has 0 low end but the top screams?
A slipper clutch just won the supercross championship...
You're going to ignite a firestorm here but, I like to polish parts to reflect heat verses for flow.
What about a movable velocity stack like the r6 has? That would help broaden out the low and top ends. Too much weight? A single one probably wouldnt weigh very much. I just posted the new tm which comes with a fixed velocity stack, but sport bikes have had variable height ones for a while. Was it tomacs bike where the side plate fell off and you could see there was a velocity stack in there?
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Not dirtbike specific, but I thought we would see more development into camless engines by now. Completely variable electronic valve actuation opens up some interesting possibilities, you could theoretically even ditch the throttle body. I probably lack an understanding as to why this isn’t pursued harder with all the advantages on paper, but it’s more fun to think about than sticking phasers on what we already got
Yes sir! Mid 90's on the twin chambers correct?
Kenny took it out a few rounds into sx this year. Went back to a traditional style clutch.
Speaking of variable cam timing, can we get @williamsmotowerx to chime in? I could have sworn at one point on his website he was developing that for a motocross application. Curious if the space constraints or simply costs kept it from taking off.
Chassis that can be adjusted for rigidity. Kind of crazy that the same chassis racing Anaheim 1 is used by a slow, old vet on an Mx track.
I’ve seen MotoGP bikes with sections of the frame where differing stiffness pieces of carbon fiber bolt to the frame to alter the feel of the bike.
Just having maybe two options on a production frame would make us regular guys and factory riders happier. Just a thought.
My original VVT design, early 2014 was literally exactly like what the GSXR came out with in 2017. Should I have patented it? Nah, too much money, would have never received anything from it.
I never made those pieces, but had them drawn up in CAD. The reason I didn't go forward with that design, it just wouldn't fit under the valve cover and timing chain galley without cutting and welding.
The next design used pawls that swung open under RPM and retarded sprocket. It still required grinding on head and valve cover, just no welding.
I built a CRF250R with the system, got to ride it, dyno it. It really was phenomenal. Bike went overseas to a customer. He loved it, but it started failing after 5 ish hours.
I don't have a website anymore, I just use Instagram. I still have some of those original parts.... I should put a pic on my page.
I'm pretty sure the 1994 RM250 had the first production twin chamber.
I thought so too. I could have sworn my buddies were all excited to get them on their 94 RM's . I'm pretty sure they were the first production bikes with them. Honda was later . I wanna say it was 97 for Honda?
I think it was whenever they went back to Showa because my buddies and I tried all kinds of crazy "bypass mods" and such with the KYB stuff that came on the 95 and 96! Edit: And my parts counter guy even popped for a set of Paolis or something that came on the CREs.
As mentioned a cam less 4 stroke with solenoid operated intake and exhaust valves. VVT is nice but engines are getting more complex and expensive. Let’s keep it simple and go back to 2 strokes. There is so much new tech out there now for 2 strokes, that the moto side hasn’t touched.
I'm with you on the two strokes, but what new technology besides FI is there?
2 stroke tech keeps progressing in the snowmobile market. Yamaha tried their 4 stroke push with sleds,but failed and eventually dropped out of the sled market.
BRP, Ski doo owns and uses Rotax engines. Some of the tech is:
Direct injection
Forged crankshafts, that lube the bearings similar to a 4 stroke.
3 stage electronically controlled power valves
Electric start that uses a capacitor instead of a battery and the stator is also used as the starter motor. All to save weight. The engine is manually started and it charges the capacitor. It will hold a charge for about an hour.
Reverse is actuated by pressing a button, the engine slows down and reverses direction. It runs backwards.
I have an 850 twin with a single pipe that produces 165 hp and idles like an electric motor at 1200 rpm. 9000 miles and the motor is untouched except for 1 set of plugs.
Here's the Thing :
It Ultimately comes down to Cost = what We as Consumers are Willing to Pay.
I'm Not knocking Any ideas / thoughts put forward here, but, a Significant Bitch by nearly Everyone, is how expensive our Sport has become.
Innovation Costs - High, or even Mid Level Tech Costs.
Mind you, when you see - for just one example of 'Tech Adoption' - all of these base level commuter bikes with EFI, it does show you that Techy Things can become affordable / cheap to produce.
Lol apparently theyre now selling kits to put a carb back on the fi bikes. Awesome!
Pit Row
I always thought geometry flip chips would be great on a race bike like you see on mountain bikes. Two different upper shock mount positions, to change leverage progression or rear end ride height. A couple different slots for the swingarm pivot to fit through so you can have a high pivot for lots of rough chop (outdoors) or a normal/lower pivot for tighter racing with less chop (sx). What about offset headset bearing cups to change head angle or the effective reach of a bike? Two mount points for lower arm on rear subframe so you can have a high or low seat height?
I dunno, just seems weird that mountain bikes vary so much, but Mx bikes are so set in stone. Even just a small, medium and large frame size would be amazing. Motos are great if you're average height, but small and tall riders are really penalised.
I love carburetors. So simple and easy to work on. Direct injection on snowmobiles came about because, tree huggers were complaining about pollution and global warming. So the EPA put limits on exhaust gases. Direct injection came about by necessity. A direct injected 2 stroke is incredible. It starts instantly, idles perfectly and is smooth throughout the powerband. I hated the complexity at first but after 20,000 combined miles on different sleds. The only maintenance I have done was change a gas filter.
Is that why they use an oil pump for the bottom end, to somehow try to limit what comes out of the pipes? It is N/A right, because with some kind of supercharging, I can see them not having to use pre-mix at all? (eliminate primary compression all together and just push air into the transfers) Edit; When I was in grade school, I designed a V8 two stroke like that and thought it was creative, until I found out that's how a Detroit diesel basically works...
https://youtu.be/eu3NEPSBfUs?si=7ID8lU652Yc6A-LM
You’re absolutely right. It uses an electric oil pump to vary the amount of oil being pumped through the engine. At idle so little oil is used that there virtually no smoke.
This an older video. Ski Doo does offer a turbo charged 850, 2 stroke. Instead of a intercooler it uses a water injection to cool the intake charge.
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