[killer1994]

Hey everyone I am brand new to the forum,
I know there has been many threads on jetting, but I none of them really have explained my question. I have read everything on nightrider.com about this, but it still doesn't help me out fully. I have an 01 night train that I bought last year and put on Vance and hines longshots (no baffles), screamin eagle a/c, and dyno jetted the carb. All this I did last year after 5000 miles. The bike currently has 17000 miles on it, YES that is correct, I ride my ass off. Anyway, after I put the mods on my bike she ran great. no popping, sneezing, farting, or back fireing. I was very pleased. However I took it in to get some waranty work done the begining of the year (primary gasket was leaking along with rocker covers) when I got it back it was runing ok, but just didn't seem right. welll it started to get worse so I looked into it. Started backfiring, popping, farting and sneezing. Found out that some how my throttle cable and idle cables became way out of wack. Idle cable was adjusted as short as it would go and throttle cable was only coming up less than half way to the throttle cam stop. so I adjusted that and fixed all my flat spots and carb problems. real nice response from throttle now. Then I tightened all my exaust and manifold bolts and seems to have helped tremendously on the backfiring (no more actually). I replaced the plugs recently also. while washing my bike I noticed that the inside of my pipes are really sooty and black, so I pulled out the plugs and found that after only a few days they were also the same. This indicates a rich condition. After reading your threads I see everyone is turing out the idle/air mixture screw about 2 1/2 turns, ny dynojet instructions indicate 3 1/2 turns out.....could this be causeing it to run to rich? I have also read about changing the slow jet to 45 Mine is stock so I believe it is a 42 will this help? my main jet is per dynojet instructions for my set up. I believe on up or down from stock can't remember. I want to run as close as possible to perfect combustion and right now it is just too damn rich for me......any suggestions....could the throttle cables have caused this and maybe now it's fixed.......

THank you

 

[killer1994]

Also forgot I have added the sreamin eagle performance ignition that has 6200 rev limiter and timing change

 

[Guest]

I know a few guys with the Dynojet kit who never could get their carbs dialed in, always too rich always bad mileage. They ended up going back to the stock carb setup with one or more of the following mods: increase slow jet 1 size from stock, increase main jet 1 size, shim stock needle (using a Yamaha shim for Kiehen carb), change to the needle from a 1988 XL.

I have part #'s on the Yamaha shim and the XL needle around here somewhere if you need them.

 

[xrystl]

Killer , we have never had any luck with the Dynojet kit , other than increasing fuel consumption there seems to be no beneficial results on the Harley CV carb , the dyno tech has removed more Dynojet kits than he has installed (they seem to work well on higher rpm machinery, R6 R1 , etc )
Best jetting results are obtained by dyno tuning (requires a competent operator) , this is a one off cost unless you make further modifications, it's money well spent !!
Regards . X .

 

[rickpoco]

try the august 2002 issue of american rider magazine, it has an article on the right main jet, it seems like a good magazine I just started getting it.saferiding rickpoco

 

[HIPPO]

There is actually nothing wrong with the Dynojet kits, and as a matter of fact their needle is my favourite needle.

People just get confused because the jet sizes with this needle are radically different from the sizes you would use with a HD or Keihin needle. Also Dynojet jets flow different from Keihin jets even if they have the same number.

People tend to follow instructions that may no longer be up to date, like the ones in the Nightrider site and even Dynojet. These instructions were the state of the art years ago, time has proven there are better ways.

The Thunderslide kits however are a bunch of wasted money.

 

[vthor]

Hippo-
Does the Dynojet kit really increase the fuel consumption as many seem to mention, or do you feel this is due to following outdated instructions? I'm on the fence whether to go Dynojet or just do it manually, i.e. main jet, slow jet, needle.
Thanks,
VT

 

[HIPPO]

Well, this is a trick question in some ways. There have been changes in the CV carburetors that people are not aware of unless they totally disassemble them.

If the carburetor is from a 99 or early 00 then the Dynojet kit, the one that had the weights for the accelerator pump in it, was a great way to go.
I always was able to get superior response and drivability with them.
No loss of fuel mileage either.
Part of the trick is not to drill the slide as they tell you and not to change the slide spring.
If the carb is off a later bike then you can achieve close enough to the same with just needle shimming and jet changes, so in this case it wouldn't be worth it to spend the money.

Wether CV or Mikuni, they are real simple, all you have to do is look and listen to the bike and you know what jets and settings they will take.
The only thing that may throw you for a loop are those straight pipes as they sometimes require the strangest jetting, but no one that is serious about performance uses them anyway.

 

[vthor]

I appreciate the detailed reply. Completely answered my question and I know what I gotta do...
Thanks,
VT