WHERE THE F**K DO YOU GUYS GET ALL THAT INFO ON ALL THE CARBS

 

This is how I know so much about the Qwilksilver Carburetor. I have the first one. Back on or about the first of September I called Edelbrock and ask if they were going to make one for the DS650. They said yes but they need a DS650 to work on so I lent they my DS650 for about three weeks of R&D work and dynoruns. At the same tdpoter also called but he lives in Florida about 4000 miles from Edelbrock were I live 75 miles from them sorry tdpoter. The people at Edelbrock ask that I say nothing till the carburetor was done so I keep my world. Tdpoter was still talking to Edelbrock and they keep him up on the progress of the carburetor. Now I am working on getting the air/fuel mixture. I had the idle to mid-range working great last weekend but the top end was way too lean Edelbrock sent me some more needle’s to pay with. So it back to the dunes this week end and it is hard work but somebody has to make the sacrifice. If any body want any more info let me know.

 

Just got back from the dunes the news is getting better. I still need more fuel at the top half of the rpm range cause it is still too lean. I am now getting a slight white color on the plugs with just a hint of brown color. The low too mid-rage power is great. My drag stars are getting better thanks too ScoobyDFW. I made one bad start where I did not lean over the handlebars and all I saw was my gas cap. Talk about a major wheelie all most went over backwards. The bad news is I did not get to try the next larger needle I cut my right thumb back at camp. I was in the process of changing to the next larger needle. When I cut my thumb on the metal tab that hold the slide to the throttle it is very ,very, very sharp. So latter this week I will put in the next larger needle and head back out next weekend.

 

I am a little concerned that Edelbrock sent you out to test this carb. Didn’t they even tune in on a dyno? It sounds like they just fit an existing carb on there and let you test it.

 

They did dyno tune it but when I got to where I ride 90% of the tine it was a different animal. On the dyno runs it show great pick up in the low to mid range of about 3 hp. Edelbrock is at about 2500 feet Elv and I ride at about 220 feet Elv. I am going to try a leak down test I have done it on a 2-stroke. I want to see if I have air leak on the intake side. This could be my lean problem.
Due you have any idea that might help.

 

An air leak could cause it to be lean, I've never done a leak down test, so don't know what that will show you. Visual inspection has always worked for me.

As far as tuning it, an onboard air/fuel monitor is a good idea. ScoobyDFW can tell you all about them. I have been thinking about getting one myself. Of course, looking at gauges while racing across the sand at 70+ mph sounds kind of dangerous.

I'd like to have an onboard monitor for rpm and O2 connected to a laptop where I could record all the data while riding/racing and then stop and see how it ran.

 

With the engine running, spray some Quick Start (Ether) around the carb area, gaskets and such. If there is an air leak, it will change the idle temprorarily (as long as you spray the area).

This should help determine if it's an intake leak.

Good luck,
CRT_Leech

 

Thanks for the info CRTLeech and tdporter. I am going try the ether first. Called Edelbrock they also think it might be an air leak. I have installed the largest needle in a 4-stroke engine that they have work on. If I due not find any air leaks they have two more slides to try.

Thanks for the help
Bill

 

It is all most done. I did find an air leak on the front hose clamp on the carb I had to tighten it about three turns. Still need the larger needle. Now it pulls hard 1st to the middle of 4th gear. I have to seat on the gas tank on a hard take off cause in 1st, 2nd and 3rd gears. The front wheels are in the air otherwise. So now the air/fuel mixture is all most right. Is just a little rich at idle and just lean at full throttle. Edelbrock is going to send me some PRODUCTION slides later this week or early next week. I need the new slide cause I have leaned out the needle as much as I can with the adjustments on the carb. If any body got any more question send me an e-mail.

Bill

 

Why guess about the jetting on the carb,jet it the right way. If you guys want to do it right put a main jet in that you know will probably be to big take your machine out run it full throttle in 3rd or 4th gear if it coughs and sputter you know the main is to big install the next size smaller jet and ride it again only pay attention to how it runs at full throttle when you get it to were it runs good at full throttle you have the jetting right now it's time to set the needle. Raise the needle by lowering the clip ride the machine and pay attention to how it run's from 1/4 to 3/4 throttle if it sputters drop the needle one notch at a time until it runs right. It will take a little time but you will be alot happier knowing that it is jetted right. Have any questions let me know.