Call me ignorant but...

[greenhorn]

This is what public forums are for right?

I saw a bike on trademe, an Aprilla, advertised as an automatic. Is this correct? I did not know there were automatic motorbikes.
If there is would anyone here in their right mind buy an automatic?

[Antallica]

I saw a Honda VTR250 advertised by a dealer as an Auto once. Next week it was changed ;).

What model is it?

[greenhorn]

Its an Aprilla Pegaso 1998...

http://www.trademe.co.nz/Trade-Me-Motors/Motorbikes/Road-bikes/Sports-tourer/auction-11429204.htm

[vifferman]

Nah, whoever's advertised it has ticked the wrong box. I've seen several vehicles that I know are manuals advertised as automatics. Just carelessness.

There have been automatic bikes, but not for a while.

[riffer]

This is what public forums are for right?

I saw a bike on trademe, an Aprilla, advertised as an automatic. Is this correct? I did not know there were automatic motorbikes.
If there is would anyone here in their right mind buy an automatic?
Is that the Aprilia Pegaso?

I think they meant to type "650cc automatic decompressor", but I would speculate the entry field for motor description only has enough room for
15 characters....

[greenhorn]

so... more ignorance coming...
What is an automatic decompressor? Is that like when you open the valves on your tyres and they decompress automatically? :confused2

[riffer]

so... more ignorance coming...
What is an automatic decompressor? Is that like when you open the valves on your tyres and they decompress automatically? :confused2
Okay, you know a big single is kinda hard to kick over? Like, say an old XR600? Well a decompressor relieves some of the compression on the bike when you kick it over, so you don't end up getting it kicking back and throwing you up in the air or hurting your ankle.

Well, most big singles with decompressor's (like the big XR's) used to have a lever on the head you could push to help you kick it over. Once the bike fires, it pushes the lever back, closing off the valve and giving normal compression.

An automatic decompressor does this automatically.

[pete376403]

A means of lifting one of the exhaust valves to reduce compression when the engine is being started. Big Honda (and possibly others) had a decompressor connected to the kickstart. Wimpy electric starters can't turn over the engine on full compression, so there is some means of lifting a calve when the starter operates. I recall the first electric start 650 Yamahas (XS1) had a trigger type lever on the bars that operated the decompressor and the starter together. Old Brit singles had a lever on the bar to lift the valve.
My chainsaw has a decomp valve for starting also.

Some big two strokes use a decompressor valve as an engine brake. makes a glorious farting sound. It works as a brake because; in a closed cylinder, the air is compressed as the piston goes up (ie puts a load on the engine) but acts as a spring when the piston goes down (ie puts energy back into the crank.) The decompressor bleeds some of this air out (as the piston goes up) and drawing the air back in as the piston goes down takes energy from the rank as well. Prove it with a bicycle pump, holding a finger over the air hole. Then try pumping with the air hole only partially covered.

Now that trail bikes have proper brakes the decompressor probably isn't used as much, but back in the days of drum brakes which stopped working arfter the first water crossing, decomps were a good way of controlling the bike on muddy downhills

[boris]

i think honda made a cb750 auto

[greenhorn]

Thanks for all your information.
No one tried to pull my leg with thier answers either... :niceone:

[riffer]

Thanks for all your information.
No one tried to pull my leg with thier answers either... :niceone:
No such thing as a stupid question greenhorn... only stupid answers.

[FROSTY]

well someone has to do it
Greenhorn you're stupid :Pokey:
-Mate thats like saying hit me gwan I dare ya hit me lol
Actually guys um a bit of puter geek stuff here.
It seems that the TM guys were updating some protocols (ya can tell im not a puter geek aye)
When they did it they were updating transmission options and everybodys transmission options reverted to auto.

[Devil]

well someone has to do it
Greenhorn you're stupid :Pokey:
-Mate thats like saying hit me gwan I dare ya hit me lol
Actually guys um a bit of puter geek stuff here.
It seems that the TM guys were updating some protocols (ya can tell im not a puter geek aye)
When they did it they were updating transmission options and everybodys transmission options reverted to auto.
Ah so in short. They fucked up, but just blame it on "Computer problems" heh.

[greenhorn]

O.K i dont mind admitting i'm stupid but....
Someone missed a BIG opportunity to spin some bollocks about what a automatic decompression was...

I did hear it was an accessory fitted to dirt bikes for extreme riders who when going through very deep puddles needed the automatic decompression switched on as the bike would rise up out of the puddles too quickly and a build up of nitrogen in the bikes fuel system would cause an attack of the bends.

I may be stupid but I AM full of bollocks. :moon:

[riffer]

Might I suggest you ask about hydrocillators then?

[FROSTY]

ACtually --there have for a few years now been big-500cc "scooters"
which are auto's and Gilera just introduced a fully automatic concept bike . So ya might not be full of bollocks after all dude

[gav]

Isnt the Pegaso elctric start only? Does it even have a kick start?

[aff-man]

Hey i just read about an "aprillia" i think that is coming out with an automatic gearbox. Apparently they have been testing for a while. I think it was in one of the two latest bike traders, got a pic of the gearbox and everything. So hmmm they are out there people

[Posh Tourer :P]

The CB250RS has a decompression lever which is actuated with the kicksart. Just runs a cable from a lever attached to the kickstart up to the top of the pot.

[riffer]

The CB250RS has a decompression lever which is actuated with the kicksart. Just runs a cable from a lever attached to the kickstart up to the top of the pot.
Don't the CB250RS and the XR250 share essentially the same engine?