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easy way to tell if an S has been jetted?

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howdy collective thumpers,

just bought an 04 S and have been loosing sleep and job productivity trying to read as much on this forum as possible.....TT is the best forum I have ever visited!!! :cry::applause:

My question is about trying to understand if there is an easy (not taking the carb apart) way to tell if the bike has been jetted.

The airbox has what appears to be a 3x3 hole, but with about half of the hole taped over :applause:

I've never ridden one of these before buying this bike, but the motor seems not terrible on throttle response and overall torque....

The guy I bought the bike from was not the 1st owner and really didn't know a thing about it, other than it was a 4 stoke, which is 2 more strokes than every other bike he's had before.

Should the fact that the 3x3 hole is half taped over be an indication that it's not jetted and after they cut the hole, the bike ran too lean? :lol:

TIA!! TT rocks and I love my new Dr. Zed S!!! :cry::eek:

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If it is taped over, I am guessing it's not jetted. If it surges from 2500-3500 RPM (roughly I know there is no tach) then it is stock. The other thing you could do it use a mirror and check the bottom of the carb. If the 4 phillips screws are not in perfect condition then it has been messed with(they basically strip out when you try to take them out to re-jet) Also on the bottom of the carb is where the Fuel mixture screw is. If you can see a slot where a screw driver can adjust or you have a large screw head you can move with your fingers it has been modified as well. Stock the fuel screw is capped off so you cant adjust without pulling the plug out of it.

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I know when I got mine with just a pipe and KN filter it back fired allot and had a big dead spot right off the throttle, and it was not jetted. Kelly

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good tips.....yeah, my bike runs fargin great, no hesitation, backfire or anything.....

EXCEPT....a very slight hiccup at hiway speeds only.....5th gear 75-80 mph, feels like the ignition is very rapidly cutting on and off with constant throttle....only ridden the bike twice on the hiway and the bike has D606's, so I wasn't sure if this was a function of knawbs on the hiway or not......it's so slight and subtle, that it's hard to even put one's finger on exactly what the symptom is :applause:

I guess that's my second question :applause:

oh yeah, and my bike does have some type of foam style AF....that's not stock is it?

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The stock air filter is a foam filter. Mine is light green in color (I think). As for the jetting, I agree, easiest way is with a small mirror to check the underside of the carb.

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The stock air filter is a foam filter. Mine is light green in color (I think). As for the jetting, I agree, easiest way is with a small mirror to check the underside of the carb.

yup, this one's light green.....sounds stock and that may be another indication that my bike's not jetted.....will check with a mirror and flashlight when I get home from Denver on Sat.

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Read through this pdf.

http://www.goodaleportal.com/index.php?option=com_docman&task=doc_download&gid=8&Itemid=42

I would suggest taking the tape off and re-jetting. The real performance from the 3x3 Mod is two fold: the amount of air that is de-restricted, and from correct jetting. With stock parts it is doable, but what the jetting kits (both JD - James Dean and DJ - Dyno Jet) offer is a special tapered slide needle, which from my understanding allows for a smother transition between fuel circuits in the carb. and correct A/F (air to fuel) ratio throughout the throttle range. Since about half of your 3x3 hole is tapped over, you are not benefiting near as much as you could be. But I understand if there is a money restraint. I know I can't get my wallet back from my Dr. Z.

On your second question, sounds like it is carb. related. A few things can be causing your stumble. Wrong jetting, incorrect float height, fuel petcock issues (try it on pri), or just simply hitting the rev limiter. When this happens, are you pegged? Does this happen in any other gear?

Chad

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Tthe best way to tell if it was jetted or not is to pull he carb out and look at the jets. From what you describe it sounds like someone tried the 3x3 mod wthout jetting t and then taped up the hole rather tan get the right jets. its very easy to jet a stock S

To be sure I would pull the carb and pull the jets. a good indicator is going to be the pilot jet. If is is a 25 than someone tried it.

A good starting point for a S with the 3x3 mod is:

142.5 main jet (stock)

25 pilot jet

4th position on needle

this is assuming you are going to use the Dyno Jet kit.

Check it out and if it is not jetted you can get some real performance from the 3x3 and a jet kit. Congratulations on the new bike.

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awesome, thanks!

I would suggest taking the tape off and re-jetting. The real performance from the 3x3 Mod is two fold: the amount of air that is de-restricted, and from correct jetting. With stock parts it is doable, but what the jetting kits (both JD - James Dean and DJ - Dyno Jet) offer is a special tapered slide needle, which from my understanding allows for a smother transition between fuel circuits in the carb. and correct A/F (air to fuel) ratio throughout the throttle range. Since about half of your 3x3 hole is tapped over, you are not benefiting near as much as you could be. But I understand if there is a money restraint. I know I can't get my wallet back from my Dr. Z.

yeah, for sure if I can easily determine that it hasn't been jetted, I'm going to do it....

On your second question, sounds like it is carb. related. A few things can be causing your stumble. Wrong jetting, incorrect float height, fuel petcock issues (try it on pri), or just simply hitting the rev limiter. When this happens, are you pegged? Does this happen in any other gear?

Chad

hmmmmm.....I'll try the 'prime' setting and see if that makes a difference....if it does, would that point to a lean condition?

definitely not hiting the rev limiter and I'm not wide open throttle, because the bike will still accelerate/gain speed fine at those high speeds, but that's sorta what it feels like to me.....like an ignition miss....and it only happens in 5th gear, at those certain speeds...very puzzling :applause:

I'll try the prime thing.....what does that do, richen the mixture somehow?

awesome, and thanks for the answers cmg and dman....I have a direction to begin now! :applause:

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Can anyone tell me how to find the elevation of certain cities in the US? Is there a website reference? Also, what would be the default James Dean jetting recommendations for up to 3000 ft elevation on a 2006 S model.

I'm about to take the $100 plunge on the JD kit, extended mix screw, and float boal hex hardware in prep for my 3X3 mod this spring.

Eric

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I'll try the prime thing.....what does that do, richen the mixture somehow?

no, if the "on" is working fine, the carb produces a vacumme that is needed for "on" or "res". the "prime" lets fuel flow free, hence don't let the bike sit in the prime setting.

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Can anyone tell me how to find the elevation of certain cities in the US?

Eric

i like "google earth" :applause:

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