Please can someone tell me

[Spookey]

What does the PR1 stand for on the fuel tap...Yes I know it's a blonde question, and I am blonde. Just bought my bike the tap is on reserve and because I'm unsure of what PR1 stands for I daren't change.

[dolepineapple]

welcome to the board!
don't worry about asking questions because in the end,
you're probably helping someone else who had the same question
and was too chicken to ask

it's actually 'PRI' and that means prime
This means that gas is only flowing to the carbs and not to the rest of the engine.  This is not what you want

You want the gas to be set to 'ON'
which means that gas is flowing everywhere (this is the setting you will use the most often)

If you run out of gas and your bike dies, set the valve to 'RES' which stands for Reserve (you gas tank actually has a little bit of reserve gasoline just in case you run out and need a bit more to get you to the nearest gas station)

hope this helps
and welcome to the sport of riding

cheers,
joel

[Dima26]

I guess, that' PRI (not PR1)

You put it there if you ran out of gas or when the bike was sitting for a while to allow the fuel to get to the carburators.

[Dima26]

I was late :x

[Spookey]

The tap only seems to have 3 positions Res and PRI or right down to the bottom which I am now presuming is where it should be there is no mention of ON, am I presuming correctly, as I live on my own if I stuff up then I don't have anyone to save me...AAARRRGGGHHH

[dolepineapple]

that's right
at the very bottom, the valve is ON
THIS is the setting you should be at when riding

[Dima26]

What year is it?

[Spookey]

I'm testing to see how many K's I can get out of a tank>>>I gues you guys are all in Miles?

[Dima26]

1 Mile ~ 1.61 km

I usually get 160-200 miles => 260-320 km.

[Spookey]

Thanks >>>so how many miles to the tank then?
U know us females are a helpless lot sometimes.
The guy I bought it off reckons 290Km's

[Spookey]

read properly first...Hey thanks I'm sure I'll be back with more questions

[Dima26]

Yep, I guess, he was right

[Kerry]

'PRI' [...] means prime
This means that gas is only flowing to the carbs and not to the rest of the engine.  This is not what you want

You want the gas to be set to 'ON'
which means that gas is flowing everywhere

It probably doesn't matter in the context of this thread, but I feel obliged to clear up a misconception.

The main difference between the ON and RES and PRI positions is in how the fuel gets from the tank to the carbs.  Once the fuel makes it to the carbs it IS available to "the rest of the engine".

In the good old days, fuel switches had two settings: ON and OFF.  When the switch was turned to ON, gravity pulled fuel down out of the fuel tank and through the hoses to the carbs.  When a bike's engine was turned off, the fuel stopped flowing ... unless the "little stoppers" in the carbs (float needles) were worn out or dirty and didn't provide a good enough seal.  When that happened, the owner would come out to go for a ride and find a tank's worth of fuel spreading out on his driveway or in her garage.  Turning the fuel switch to OFF prevented this kind of accident, and when I took the MSF course in 1999 it was still part of the sequence they taught.  (Perhaps it still is?)  Something like Kill Switch, Key to OFF, Fuel to OFF, Sidestand Down, etc etc.

At some point, somebody realized that there was another way to prevent the overflowing carburetors problem.  They designed a fuel delivery system that would only pull fuel from the tank when the engine was actually running.  That's the kind of system our bikes have.

That's why our ON / RES / PRI switches don't even have an OFF setting.  There is a diaphragm inside the switch which is part of both the ON and RES(erve) delivery circuits.  In either position, the diaphragm blocks the flow of fuel unless the engine is running -- and vacuum pressure is being applied via a hose from one of the carburetors to the fuel switch diaphragm.  This pressure "sucks the diaphragm out of the way" and opens up a path for the fuel to flow through the switch to the carbs.  When you turn the bike off you have effectively turned the fuel switch to OFF, because the diaphragm snaps back into place and prevents any further flow.

Now, suppose you drain the carburetor float bowls so you can remove the carbs (or clean them or whatever).  You reconnect the hoses (after remounting the carbs or whatever) and try to start the bike.  Hmmm ... it's not starting!  Crank, crank, crank.  Arrgggghh!

Why is it not starting?  Because there is no fuel in the float bowls, and therefore no fuel being sucked up through the jets, and no fuel/air mixture being sent to the cylinders, and so nothing for the spark plugs to ignite, and no way to kick off that wonderful, self-sustaining 4-cycle combustion process.

You need some way to prime the carbs with fuel again, so the system can get back to its normal operating conditions.  Wait - did I say "PRIme"?  Yeah, I did!

The PRIme position on the switch is just like the ON position from the "good old days".  It provides a gravity-activated, barrier-less path for fuel to flow from the fuel tank to the carbs.  Setting the fuel switch to the PRIme position for a matter of 10 seconds or so will result in the carburetor float bowls being full of fuel again.  At this point you can switch back to the (modern) ON position for normal operation.

Make sense?

Whew!  I hope nobody died of boredom.  Did anybody read this far...?  :dunno:

[Dima26]

when I took the MSF course in 1999 it was still part of the sequence they taught.  (Perhaps it still is?)

It still was in October 2004 when I took my course.

Whew!  I hope nobody died of boredom.  Did anybody read this far...?  :dunno:

I did It couldn't be put better

[John Bates]

......... the tap is on reserve and .............

I wonder why? :dunno:

Maybe the previous owner ran low on fuel , turned it to "res" and never turned it back?

OR

Maybe the fuel lines at the tank are reversed (like mine after someone reassembled using Clymer) and now "res" is "on" and "on" is "res"?

I don't wish to confuse you Spooky but things like this happen.

[scratch]

that's right
at the very bottom, the valve is ON
THIS is the setting you should be at when riding

And, also, when you are not riding. This prevent fuel leakage. Not that there would be much otherwise. Just better to be safe.

And, WELCOME!

[Spookey]

to take in, thank goodness the thread stays so I can read it over and over.
Gotta sound like I know what I'm talking abt...LOL
I'm doing a morning ride with some new guys this morning...being Sunday here and don't want to suddenly stop...
You could be right abt it being on res when I bought it, it didn't have a lot of fuel in it. The dealer I bought it from didn't even bother explaining anything to me abt it.
Just take my money and run...
Well once again thanks guys

[GirlScout500]

I for sure did not die of boredom reading the killer explanations for the three little settings on my favorite part...the petcock.
Thanks for asking the questions...and giving the answers. Currently my hands are filthy from cleaning my frame, and I've beenstaring at those three positions for about an hour! Funny what I find on my break...

[Dima26]

I for sure did not die of boredom reading the killer explanations for the three little settings on my favorite part...the petcock.

:lol:  :lol:  :lol:

[Spookey]

when I went riding today I felt really knowledgeable LOL
It's great to have somewhere to go ask questions.
And guess what there will be more coming from me