Will you guys chill out?! Geez people, as long as you like your quad, and you can have fun on it, it serves its purpose. Own a Banshee? Like it? If so, good. Own a DS? Like it? If so, good. What, are you trying to make each other not like their quad? What's the purpose of that? I don't see any. Anyway, back to the topic...

 

Being a loser has nothing to do with what ATV you own, or who made it. Being a loser, is all in how you act. You being an owner of a non Bombardier ATV (please note, I do NOT own a DS650 ) coming in here and bashing a machine that someone else loves and just paid money for, really makes you look bad. So do yourself a favor, do everyone a favor, do not come into the Bombardier forum and bash the Bombardier. Come to this forum as well as and any other, and contribute non-bashing and non-biased information and your knolwedge and thoughs will be welcomed.

 

SCRAMBLERS, My carb tuning is going great now. This weekend the Air/Fuel Monitor came in handy. I took the DS out to a new riding area and dragged it against some modified 2-strokes. The DS was bogging a little and losing in the drags. I noticed that the Air/Fuel Monitor was reading full scale rich. I was skeptical of the meter, so I removed the air filter to see if the DS ran better and to confirm that it was running rich. It turns out that the meter was telling the truth. The DS ran noticeably better without the air filter, indicating a rich condition. I switched from a #97 jet needle to a leaner #98 jet needle and this solved the problem. I believe what happened was that the temperature and humidity had risen quite a bit over the past week, which reduced the density of air causing the richness. When I went back to the drags, the DS was no longer bogging and I was now winning the drags!

I am not running the dial-a-jet, bigdaddy is. I am running the accelerator pump. I don't know which is better, but they both appear to REQUIRE a lean condition in order to work. I would guess that which ever one has the fastest response time is the better solution. As it stands now, I don't think I will need a dial-a-jet.

I'm hesitant to keep posting my jetting because the optimal jetting will be different for other climate conditions and even from one bike to another in the same climate conditions! But OK, here they are:

(Note: These are not my optimum settings, but they are pretty close. I'm suspicious that I could still be a bit rich in the pilot & jet needle, and a bit lean in the main jet)

Main Jet: #150
Jet Needle: #98, in leanest position
Pilot Jet: #27.5
Pilot Air Screw: About 1 turn out
Accel Pump Nozzle: #70, Stream strikes jet needle
Accel Pump Stroke: About 0 to 3/4 throttle
Air Filter: Stock filter(dirty), air box lid off
Altitude: Less than 1000 feet
Temperature: 93
Humidity: 40%
Dew Point: 70

Air/Fuel Ratio: 13.6 (0.85 Volts) This assumes 1200 degress F

Plugs: White insulator, with partial gray shading

I might post some tips on how to get the pump running correctly, if people are interested. You may need to get some jet needles, main jets, pilot jets, etc. to get the pump working correctly.

 

Out of curiosity, where did you pickup the fuel/air meter? Also, where do you install it, the exhuast? How difficult was it to install?

What can you tell me about the dial-o-jet? I don't know the first thing about it (perhaps a website).

Thanks!

 

Im just curious as to the problems scooby is having. I have modified a few four strokes but never so far as to have to change the carb, although usually i have had to on most 2 strokes.
in my opinion if you are not going to go with a different cam setup you probably( i said probably) do not need a new carb given you can use a high flow filter and just rejet. also another option is reboring the stock carb larger. I know the DS is the Big Daddy but never have i ever had to buy a carb just to do a pipe and given this carb is only 3mm larger.Also consider that the BMW street bike setup includes 2 32mm throttle bodies and Fuel Injection. In my opinion i would first buy a CDI box with higher rev limit, then a new exhaust (not RW) then if it didnt work up to expectations bore the stock carb and use an open airbox. but this is just my opinion. I hope they get the bugs worked out soon. as im looking to buy as DS650 after I see that i dont have to have the NEW Yamaha Quad or the new Kawasaki race Quad, But Cannondale with fuel injection may be the way to go. Or you might just swap their fuel injection to the DS650.

 

chrism101 pointed out a good manual on the 45mm carb at (the PDF file is about 2.05MB):

http://www.mikuni.com/carbtech/pdf/t...er51000wtm.pdf

 

chrism101, Problems? What problems? I have got that carb running sweet now, it just took forever getting there! By the way, Ron Wood Racing was not selling the parts individually, so we were stuck with the carb, pipe, & rev box. I think the reason to go with the flatside carb is for better throttle response over a CV type carb. The 3mm diameter increase is probably less of a factor, unless you go with stage III where the port diameters are matched. With the 45mm carb setup correctly with the proper size jet needle and pilot jet along with the accelerator pump connected, this carb does have better throttle response. I'm sure you could play with the CV carb and get it working a little better too.

 

KawasakiKid, Here are some links to browse:

www.extrememotorsports.com/gscat/afgauge.htm

http://www.mesaperformance.com/web_s...l&category=yes

www.autometer.com

www.burnsstainless.com/hardware.html

www.headersbyed.com/misc.htm

splitsec.com/

zcarmag.com/tech_info/O2_2.html

I bought the Split Second EGO1 O2 sensor and the Autometer Air/Fuel Monitor. I had an oxygen sensor boss welded to the header pipe near where it connects to the muffler pipe. I also have the DS650 service manual that shows the electrical wiring diagram which helped with the wiring.

www.thunderproducts.com/dial_a_jet.htm

dial-a-jet.com/

 

the big yamaha comes out tomorrow! we get to see what the hell it is? also word is that Polaris has a DS650 in the R&D lab so they are going to bring out a high perf too. with cannondale due this fall and kawasaki making a new racer also, the only people who arent seems to be Suzuki, maybe theyll suprise us. GAS GAS is still in development as is Husaberg. Everybody is still trying to catch up with the ds 650 and im glad. If i dont end up with one of these I sure wont knock it, because they are awesome and gave new life to the sport market.
Also if any one is interested CT Racing bores stock carbs for $40.

 

In what capacity do you mean that the "Big Yamaha comes out tomorrow"? Is it going to preview at some kind of trade show, be in a magazine or are they just going to plop it off in the dealers without any kind of warning (which I find absolutely hard to beleive!)?

By the way, this is a Bombardier forum, not a Yamaha forum. I'm not going to bash Yamaha anymore in this thread, but, I am just sick of getting updates for products I don't care about.

Do you see anyone telling you the new Chevy/Ford/Chryslers are coming in tomorrow in this forum? Sure, they are cars and not ATV's, but it's not much different.

Thanks for your interest in the DS, but most, if not all of the DS owners that I have read of in this forum don't give a crap about any other ATV's that are currently out there or ones that will be coming out today/tomorrow or whenever.

Laters,
CRT_Leech