A CHAPTER ON THE RAPTOR....OR......HOW TO TURN A 20 MINUTE JOB INTO A 2 HOUR SESSION WITH YOUR BIKE.

I wanted to provide a little bit of information about the Raptor so you could weigh the good and bad and decide what is best for you.

The stock petcock is a vacuum operated affair and when the engine is running it allows fuel to flow - but stops the flow when the engine is not running and creating a vacuum.  There is an ON setting for normal use, a RESERVE setting for when you run out of fuel in the ON position, and a PRIME setting that is used when you have not ridden for a while and the float bowl is empty from evaporation (or whenever you have drained the tank or run it completely empty).  The stock petcock has a very small lever and faceplate, and it has a lot of the hardware behind the mounting screws and it can prevent you from removing the fuel tank without first removing the petcock.  On my bike it is impossible to take the tank off without first draining the fuel and removing the petcock as the back of the petcock hits the frame - while I have heard that some can wiggle things and get the tank off with the petcock stilll attached.



The Raptor petcock is not automatic and is a simple ON/OFF/RESERVE petcock like in the old days.  If you forget to turn it off and on the rare occurence that the float sticks, you will have gas running someplace.   The faceplate and lever are larger and visually more noticeable - and the ON and Reserve are at different positions than the stock petcock.  You will have to relearn where to turn the valve when you are riding and reach down to switch to the RES setting with the Raptor.  The Raptor sticks out behind the mounting screws much less than the factory petcock, and removing the tank without removing the Raptor should not be a problem.  There are some different models of the Raptor Petcock, and the one you want is for the Raptor 660 and is part number 5LP-24500-01.  Other versions have a short stem and it causes the face plate to hit the bottom seam of the tank:




Here are some side by side images for comparison:




I did some flow tests on the petcocks by having a nearly full tank and I put a hose into an empty gallon jug.  I marked the jug and timed the petcocks flow until it reached the mark - then dumped the fuel back into the tank and made the next test.  Below are the results in minutes and seconds:
Stock Petcock:  ON 2:34, RES 2:24, PR 3:25
Raptor Petcock: ON 2.15, RES 2:15
While these flow rates are accurate for a tank that is nearly full - the flow rates drop to near zero as you approach the limit of the ON position, and again as you empty the tank in the RES position.  When you are riding along in the ON position and the engine stutters......it is not providing an adequate flow rate for your throttle setting, and you must switch to RES.  When I was draining the tank in the PRIME positon a few weeks ago to set my valves the tank was low, and it took nearly 7 minutes to empty out the last gallon.


The reserve provided by the Factory Petcock is larger than the reserve provided by the Raptor.  The difference is caused by the height of the tube that provides flow to the ON position.  This could be corrected by removing the filter and extending the height of the tube on the Raptor - which may be a subject of a future tech article.  I turned each petcock to ON and let the fuel run out - then switched the petcock to RES and let the fuel run out and measured what was in the bottle.  The stock petcock provides 78 oz of fuel, while the Raptor provides 60 oz of fuel on RESERVE - this is whitout shaking the bike to get any remaining fuel out of the right side of the tank and you may get more when actually riding.  If you got 55 MPG on your bike the stock petcock provides 33.5 miles of reserve and the Raptor provides 25.7 miles of reserve.


I just looked up the price of the stock petcock on the internet and it was listed at $ 95.85 from the dealer.  I did the same on the Raptor and found a price of $ 26.76 from a dealer, $ 19.53 from Bike Bandit, and Ron Ayers had it at $ 18.46 when I bought mine.  These prices are certainly subject to change.  Parts are not available for the stock petcock from Suzuki - however there is an article on this forum somewhere about a kit that you can get that will fit the stock petcock but is missing one O-ring I believe.  Parts are available for the Raptor Petcock.

Which petcock do you you want?  The stock petcock certainly is convenient in operation - but when it stops working right parts are not easily available and if you take your tank off frequently it can be extra work each time.  The Raptor is more affordable and more durable, it is less convenient in that you have to remember to turn it on and off - but if you have been riding for a while this may be routine for you.  The Raptor has a smaller reserve and has parts available for a rebuild if it ever becomes necessary.  

I am adding these pictures of the plugging of the port at the carb.  I used a rubber cap available from most any auto parts store.  Some have suggested that these deteriorate over time.  I have placed a spare in my tool kit in case I need to replace it.

Hi Dave, I want to make a post in my blog https://79customs.wordpress.com/
And I want to ask permission for using some pics and info you provided in this forum. Of course I will add the link and the thanks in the blog.
Please tell me If I can. Thanks!


Oldfeller--FSO wrote on 07/11/12 at 13:19:33:

Hi guys.   I followed the ideas here and fitted the Raptor tap.  It worked great,   for about 3 days,  and now leaks from under the face plate, all the time, no matter what position the tap is in!  I pulled it to bits and found nothing, so I think the face plate is made from too thin a material and is distorting when the 2 screws are done up.  I've abandoned that tap and found an old Ls tap and fitted that.  
   I must say that I've found the position of the tap rather awkard, as it hits the inside of my left knee while riding.  It tends to leave me with a good sized bruise after a days riding!

           Cheers