1BEARMAN sound just like the QwilSliver I am working on. The great thing is when this carb was on it was making about 3-4 hp over the stock carb. I will be out testing again this weekend hope to get on a dyno next week.

 

1BEARMAN, I have spent so many hours between the HSR45 and the HSR42, tweaking the jetting, changing fouled plugs, etc. I bought all the jet needles - #98, #97, #96, #95. I bought a ton of pilot jets from #20 to #40. I bought a #50 and #60 accelerator pump nozzle. I have main jets from #145 to #175. I've tried with and without the airbox. What I have learned is that if the pilot circuit is not tuned perfectly, your lowend, midrange and topend is affected adversely! To even come close to having the pilot circuit tuned I had to use the leanest jet needle, #98, and a small pilot jet. The accelerator pump nozzle was too big, so I had to either disable it or run a #60 for only part throttle. With the accelerator pump disabled, I needed to have the jet needle in the richest position for midrange power, but I'm not sure it is rich enough. If the jet needle is off, the engine won't rev as quickly and the topend will be affected as well. If I enable the pump to provide some gas at part throttle, then the pilot circuit becomes to rich. The main jet is somewhat tricky too. If you go too large on the main jet, the midrange is adversely affected as well as wide open throttle. I noticed the main jet appeared to be too large because I was getting carbon deposits on the exhaust tip and the plug insulator. I decreased the main jet and this reduced the carbon deposits but it seemed like I lost a little topend power. It is not an easy carb to figure out! I have had better luck with the airbox and K&N filter as opposed to a K&N filter w/o airbox, for some reason. I have been testing mainly with a free flowing exhaust, but also a little bit with the stock exhaust and stock airbox & filter. I have a dynojet kit for the stock carb and plan on comparing it to the HSR42. If it runs better I may just give up on the HSR42 for now. I'm starting to think that there are no significant bottlenecks external to the motor that are limiting PEAK HP output.

 

I think I have got this carburetor figure out it now pull hard in all five gears. Next week I will get a dyno run done and hope to see some improvement in the top HP numbers. Then after the New Year it is back to Edelbrock for final and adjustments and fitting

 

IT IS done yesterday at Edelbrock we fine-tune the carburetor. My final needle I used was way to rich. The one I stated with produce the most HP but was too lean on top and too rich at idle. We moved up two sizes and hit a real good air to fuel mixture ratio and only lost a few tenth of HP off the top. Then Jason made some final adjustments on the accelerator pump to smooth out the power. The engine starts up very easy with this carburetor. The idle is smooth and the engine is making power all the way tell it hits the stock rev limiter. The QwikSliver carburetor is like adding a pipe to the DS650 big power gains in the lower rpm range and a little more HP on top end. The only thing left to due is to make the throttle linkage for both the twist and thumb throttles.

 

 

The QwikSliver has hit some fitting problem with after market pipe’s the only one it works with is the Alba. It might work with the Ron Woods pipe but I a not sure. It will work with the stock header and slip on mufflers. The thing I like best about it is simplicity and that you cane make adjustment from the out side of the carburetor without have to remove any thing. The DS650 starts real easy with it and the first time I took of hard I stood the DS on it back bumper, I all most flip it. The guys at Edelbrock are at Bike week now. I will get the DS back up to them for the adjustment next week. The QS was making power all the way too the rev limiter so I have added the Ron Wood CDI box.

 

cal,
that sucks about it not fitting with certain pipes. i have a graydon complete system. i want that carb as soon as it is available, but if i have to go back to the stock header forget it. by the way when is it going to be in production?

 

Bkutina don't but down the stock header and Graydon combo. Rumor control has it that Bombardier ran a lot of tests on pipes this winter and that is the setup they like best.

 

CalDS650 did you ever get that Quicksilver carb figured out? I was reading this thread and am left hanging as to what happened

 

Graydon finally gave up on this carb.they are waiting for edelbrock to finish the quicksilver and make some mods of their own and market that carb.
Bearman