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Stock Carb Mods - Summary

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  #11  
Old 02-19-2007, 01:55 PM
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Default Stock Carb Mods - Summary

Is there an update? Would like to know about the modified emulsion tube.
 
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Old 02-19-2007, 10:11 PM
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Default Stock Carb Mods - Summary

OMR first off I would like to thank you for your advice and insite, on the carb mod. I have done all of your mods, except the air bleed. I am sitting about 2000 ft. elevation. I'm running the stock needle in the 5th groove, and was wandering if you have heard of or tried cutting a 6th groove in the stock needle. My local dealer doesn't carry DJ kits. I have just about all the jets (for the main) from stock 165 up to 190. The only two pilot jets he had was 45 and 50. In the colder weather we have been having, I was running the 180 main and a 45 pilot, with your tube mod, the clear tube removed. With the lid off, I have been having fantastic results with all mods so far. I modified the factory exhaust tip, and am running a procom cdi, with a k & n air filter. I can not thank you enough, I just started to mod my cousins ds 650. I weigh about 300 lbs, he weighs about 120, I out ran him about ten times, before he started asking questions. So thanks again.
 
  #13  
Old 02-19-2007, 11:43 PM
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Default Stock Carb Mods - Summary

hagensmail,

I have raised the needle to 6 1/2 grooves. This is the highest you can go without the needle coming out of the needle jet.
Go to the local hardware store and purchase 3 metric 3mm washers. They are .020 thick, each notch on the needle is .040
Thus 3 washers are equivelant to 1 1/2 notches.

This helped bottom but still ran lean on top.

Buy the smaller air bleed jet #40 and this balances top and bottom.
I had to go 3 sizes smaller on the main jet. 180 to 165 and had to lower the needle one notch(4th groove).
The Moose jetkit is the same as DJ. The taper of this needle adds alittle more power bottom to mid.


ben362,

My health and the extreme cold weather here in wisconsin, has kept me from getting quotes for the emulsion tube.
I will be getting going shortly. Sorry.


OMR
 
  #14  
Old 02-19-2007, 11:58 PM
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Default Stock Carb Mods - Summary

Thanks OMR, I"ll give that a try.
 
  #15  
Old 02-20-2007, 01:13 AM
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Default Stock Carb Mods - Summary

OMR, have you ever considered reshaping needles or making your own?
I encountered the same top end lean condition without a lid and using a dynojet needle so I roughly copied the top end taper of the stock needle on the dynojet needle.
Modifying the air bleed is cheaper but I didn't think of it plus I knew I liked the characteristics of both needles.
 
  #16  
Old 02-20-2007, 10:52 AM
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Default Stock Carb Mods - Summary

OMR,
No appologies necessary, you getting your health back is the important thing. Just wanted to check and see if there was an update. I have done all of the mods including the air bleed and the "porting" that mystereid had up a while back. I also changed the pilot air bleed the same way as the main air jet. A definite improvement in performance on the cul-de-sac dyno. I will be doing some real testing this weekend in the desert.

mystereid,

FYI, the "bumps" that you smoothed out can be completely removed without going into any air passage. Thanks for your info.
 
  #17  
Old 02-20-2007, 03:22 PM
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Default Stock Carb Mods - Summary

mystereid,

I agree that the taper on the stock needle may have merit with the stock emulsion tube.
By matching the taper on the end of DJ to match stock may help.
The stock emulsion tube has very few holes to atomize the fuel needed. Raw fuel is why a cv carb doesnt have the throttle response like a flat slide(mid-top). CV carbs have great bottoms and with my free mods great mid.
The only way to get top is with a better emulsion tube. This matched with a different rate spring, gives the feel of a flat slide. I have only one proto type and my son refuses to give it back. You do not have to have a dyno tests to feel the difference. He wants me to mod a smaller cv for his old warrior now.
I just hope the costs is something that most riders would be willing to pay for.

OMR
 
  #18  
Old 02-21-2007, 09:16 AM
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Default Stock Carb Mods - Summary

I suppose it really comes down to your price point. Just remember when you market them that the Predator runs the same carb.
"FYI, the "bumps" that you smoothed out can be completely removed without going into any air passage. Thanks for your info." Thanks Ben, I wasn't willing to go that far and I had a spare carb[img]i/expressions/face-icon-small-wink.gif[/img]
 
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Old 02-22-2007, 12:45 AM
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Default Stock Carb Mods - Summary

I have a question about the cutting the spring in the carb. My spring had 26-27 coils and measured 4 1/4" long.
I ended up cutting a full inch off. Has anyone else found there spring to be this long?
My DS650 is a 2000.
Thanks.
 
  #20  
Old 02-22-2007, 05:44 PM
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Default Stock Carb Mods - Summary

For a very short period of time in 2000 the DJ kit came with a spring. Maybe you have one of them.

Check your needle to see if it is a stock or DJ needle. If your throttle response is too fast you will notice a slight bog at low rpm. Check this on a surface with good traction. When I was testing different springs I had one that was very weak, when I had good traction I noticed that very bottom was bogging. The spring I am presently using is actually stiffer than stock at bottom and 40 per cent lighter at top. Makes for great torque at bottom and total open from 4000rpm up.

If you have a slight bog, buy a 2005 or newer spring. Costs is under ten dollars.

Because I live in Wisconsin, I am always complaining about the cold. International falls is the coldest area in the lower states. Glad to see you like atving even in the cold.

OMR
 


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