I put on a Raptor just for ease of use.

I have a non-stock Carb (Mikuni 38mm VM) and wasn't using the Vacuum at all so decided to swap so I could ride and have a reserve again.That and don't have to remember in the spring  which way to turn it so it will run.

Aw jeez. My Raptor installation has turned into a flawed mileage experiment. Mileage on two laps of a favorite loop on first tank since installation has improved from about 62 to about 68 mpg. Same gas station, same pump. First part of the loop is, slow, twisty (beautiful, fun).

The "flawed" part comes from having added SeaFoam to that tank, which I did because my bike had very low odometer mileage when I bought it - thus had sat idle a lot - and because the bike will get relatively intermittent use over the winter. I wasn't looking for a mileage bump from the Raptor or the SeaFoam, so I never even thought to isolate the changes. But the improvement is striking.

Since the vac. hose was wet with gasoline when I removed it during the Raptor installation I'm wondering if it was wasting gas and fouling the spark plug (which I didn't check at the time and which now may be cleaner thanks to the SeaFoam). ? I can also report that although I ride pretty conservatively, there appears to be a low-end power improvement. Most importantly, however, my bike's willingness to spontaneously silence itself has not recurred.

You guys are doing much better mpg than I am...I'm lucky if I get over 42mpg it's been a good tank. (most of my rides are short and quick, very quick  )

The Raptor cured all my ridability problems about a year ago. Does anybody remember the Honda CBX? 6 CYL. A recent mc magazine had a letter from a guy who used the stock non-vacuum petcock that came on the bike recently. There was apparently a technical bulletin to replace it with a vacuum petcock years ago. His carb leaked gas into one cyclinder and the other five tried to crank. Remember the Hindenburg? It wasn't that bad   But it bent a rod on a complex engine. He had forgotten to turn the gas off as was usual to do back then on the old bikes. For you youngun's I can say carbs and electrical have come a long way in 40 years as well as oils, tires, you get the idea. Like I said...the Raptor did the trick for me.

My mileage went down when I installed my Amal roundslide carb but my throttle response is much better.  Installing the raptor just increased the simplicity and did away with potential points of failure.  In fact, changing the carb did too by getting rid of yet another rubber diaphragm.  I'm getting about 45-50 MPG these days, I think.

yep

5LP-24500-01-00

Joe F wrote on 03/11/12 at 18:39:12:


I was actually getting in the 46 range until I changed out the air filter last week. Now I'm getting 48-50 on my last 3 tanks.  About a 5% increase by putting in a clean filter.