What do you think of this bike for sale?
- Thread starter Trfsrfr
- Start date
google says
The desirability of being able to vary the valve opening duration to match an engine’s rotational speed first became apparent in the 1920s when maximum allowable RPM limits were generally starting to rise. Until about this time an engine’s idle RPM and its operating RPM were very similar, meaning that there was little need for variable valve duration. It was in the 1920s that the first patents for variable duration valve opening started appearing – for example United States patent U.S. Patent 1,527,456.
In 1958 Porsche made application for a German Patent, also applied for and published as British Patent GB861369 in 1959. The Porsche patent used an oscillating cam to increase the valve lift and duration. The desmodromic cam driven via a push/pull rod from an eccentric shaft or swashplate. It is unknown if any working prototype was ever made.
Fiat was the first auto manufacturer to patent a functional automotive variable valve timing system which included variable lift. Developed by Giovanni Torazza in the late 1960s, the system used hydraulic pressure to vary the fulcrum of the cam followers (US Patent 3,641,988).[5] The hydraulic pressure changed according to engine speed and intake pressure. The typical opening variation was 37%.
Alfa Romeo was the first manufacturer to use a variable valve timing system in production cars (US Patent 4,231,330).[6] The fuel injected models of the 1980 Alfa Romeo Spider 2000 had a mechanical VVT system. The system was engineered by Ing Giampaolo Garcea in the 1970s.[7]
In 1987 Nissan debuted their electronic variable valve timing technology called NVCS in their DOHC VG20DET and VG30DE engines. In 1989, Honda released the VTEC system.[8] While the earlier Nissan NVCS alters the phasing of the camshaft, VTEC switches to a separate cam profile at high engine speeds to improve peak power. The first VTEC engine Honda produced was the B16A which was installed in the Integra, CRX, and Civic hatchback available in Japan and Europe.[citation needed]
In 1992, Porsche first introduced VarioCam, which was the first system to provide continuous adjustment (all previous systems used discrete adjustment). The system was released in the Porsche 968 and operated on the intake valves only.
The desirability of being able to vary the valve opening duration to match an engine’s rotational speed first became apparent in the 1920s when maximum allowable RPM limits were generally starting to rise. Until about this time an engine’s idle RPM and its operating RPM were very similar, meaning that there was little need for variable valve duration. It was in the 1920s that the first patents for variable duration valve opening started appearing – for example United States patent U.S. Patent 1,527,456.
In 1958 Porsche made application for a German Patent, also applied for and published as British Patent GB861369 in 1959. The Porsche patent used an oscillating cam to increase the valve lift and duration. The desmodromic cam driven via a push/pull rod from an eccentric shaft or swashplate. It is unknown if any working prototype was ever made.
Fiat was the first auto manufacturer to patent a functional automotive variable valve timing system which included variable lift. Developed by Giovanni Torazza in the late 1960s, the system used hydraulic pressure to vary the fulcrum of the cam followers (US Patent 3,641,988).[5] The hydraulic pressure changed according to engine speed and intake pressure. The typical opening variation was 37%.
Alfa Romeo was the first manufacturer to use a variable valve timing system in production cars (US Patent 4,231,330).[6] The fuel injected models of the 1980 Alfa Romeo Spider 2000 had a mechanical VVT system. The system was engineered by Ing Giampaolo Garcea in the 1970s.[7]
In 1987 Nissan debuted their electronic variable valve timing technology called NVCS in their DOHC VG20DET and VG30DE engines. In 1989, Honda released the VTEC system.[8] While the earlier Nissan NVCS alters the phasing of the camshaft, VTEC switches to a separate cam profile at high engine speeds to improve peak power. The first VTEC engine Honda produced was the B16A which was installed in the Integra, CRX, and Civic hatchback available in Japan and Europe.[citation needed]
In 1992, Porsche first introduced VarioCam, which was the first system to provide continuous adjustment (all previous systems used discrete adjustment). The system was released in the Porsche 968 and operated on the intake valves only.
Sokay Timo, just read this and had a proper LOL
yes sometimes after a night of hard anal with Shelly, I smell cheesy
(she will lose the plot if she ever reads this)
yes sometimes after a night of hard anal with Shelly, I smell cheesy (she will lose the plot if she ever reads this)
Cheap vehicle challenge.
1,000 max for any sedan/wagon (can't be a truck).
Anythink under 1,000 max and any parts sold off it can go towards anything for vehicle enhancement.
Must have roll cage and helmet at time of entry.
500 towards suspesion and tires/wheels.
4 races:
1st is drag race
2nd is a side X side (contact ok)
3rd hill climb
4th 2 lap course rally style
Win all, take home 1,500.00 cash.
AZ desert, undisclosed area, and date (winter 2017) to be announced.
20 vehicle entry max.
Whos in?
1,000 max for any sedan/wagon (can't be a truck).
Anythink under 1,000 max and any parts sold off it can go towards anything for vehicle enhancement.
Must have roll cage and helmet at time of entry.
500 towards suspesion and tires/wheels.
4 races:
1st is drag race
2nd is a side X side (contact ok)
3rd hill climb
4th 2 lap course rally style
Win all, take home 1,500.00 cash.
AZ desert, undisclosed area, and date (winter 2017) to be announced.
20 vehicle entry max.
Whos in?
GM's stab at it doesn't seem to be mentioned, but technically it was VVT in that it cut cylinders completely out as in it could run with 4, 6, or 8 cylinders having their valves open or closed. Didn't fly for long.
They sent it longer in Canada it seemed. I was no longer working for a GM company then either, but I was still getting their tech bulletins for everything (though I was getting them via detroit diesel and allison) and that was as close I got to opening one up. Kind of a nice thought. At first the idea of running with both valves CLOSED seemed odd until you think about the compression loss being partially compensated by the "spring effect".
Been thinking I should get a 4t 250, so I'm gonna go look at this;
04 kx250f - $400
https://phoenix.craigslist.org/nph/mcy/6161773413.html
More basket case fun!
04 kx250f - $400
https://phoenix.craigslist.org/nph/mcy/6161773413.html
More basket case fun!
I couldn't do it, I took her home.
She's super clean for a basket-case.
Frame is all good, plastics and seat are in great shape.
Engine was disassembled correctly, everything bagged and tagged, new rod and bearings we're fitted at a local shop (have the receipt), cylinder & head look good.
She even came with a factory service manual AND a clean title.
I'll have another build/repair thread started soon enough...
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Good lad!
