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Discussion Starter #1
so I finally got the pilot screws right- 1/4 turn at a time until highest idle. now I am having some trouble cruising. the bike has pod filters on there which don't exactly work that well with cv carbs but I hate fiddling with air filter boxes. I know they don't make a dynojet jet kit for the early xs11's should I a. raise the slide needle or b. get a larger main jet or c. try both?
the main jet feeds into the pilot jet.
:71baldboy:
 

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Tune it.

Factorypro.com under the tech section has a tuning guide for your type of carb. You have a high reving engine.
Follow what they say. Start with the main jet, the rest is gravy.
I have pod filters on my XS400. It pulls strong in all gears up to 10,000 revs.
It will not pull max revs in top gear as it does not have enough power to combat the wind resistance.

Mains on an XS11 are around 110. You may need a selection of jets 2 sizes smaller and two sizes bigger to start with. Start with the needle in the center position.

Normal piston pressure is around 140.

Bon chance.
 

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Discussion Starter #3
I had a Kawasaki 750 with pods and a header that did well with the slide lift holes drilled out a smidge.
 

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Generalise

I had a Kawasaki 750 with pods and a header that did well with the slide lift holes drilled out a smidge.
You can not generalize with jet tuning. What you need is the correct jets in your bike starting with the main. Many backyard tuning guides will give a general overview of what is required, but that is not the way do do it IMO, and the opinion of good tuners.

A big guy and a small guy sit down with a milk shake each, to see who can suck it out the fastest. The logic being used for carb tuning says the big guy needs a bigger straw.

Follow the tuning guide, otherwise you will be messing with the bike for a very long time.

Unkle Crusty*
 

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Good advice, Crusty. Jetting can be a black art, most easily accomplished on a dyno with a fuel/air mixture detector, which can be expensive. To get it just right, throughout the range, you have to mess with the main and pilot jets, and,often, the jet needle and needle jet. More than many want to do, so they just throw in a larger main, and tweak the pilot screw, until it's 'close enough'.

Or, you could get foam 'socks' to put over the pods, to reproduce the restriction of the original air boxes and filters.
 

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Discussion Starter #6
whoa... whoa horsey... would it just be easier to throw the airbox back on. I didn't want to pay 20$ to buy an air filter.
 

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Filter

whoa... whoa horsey... would it just be easier to throw the airbox back on. I didn't want to pay 20$ to buy an air filter.
The air box can not be put on without removing the carbs. One of Yamaha's better ideas. Many run these bikes with pod filters. I use pod filters on my XS400 which is the same style of engine, just smaller. If I ever run my Midnight Special XS1100 it will have pod filters.
For a bit of fiddling it is worth it. Once the correct jets are in place, you are good to go.

A problem is: some folks run out of patience. If they put the time in to working on the problem, and less time on the internet, it might work out for them.

4 pod filters are more money than the stock air filter. But if you can not afford air filters what happens when you need new tyres?

Unkle Crusty*
 

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New tar.

take it easy, I already got a new tire.
Well okay then. How did that help with the carb tuning?
I think I mentioned already, there is a good tuning guide for CV carbs online.
It does not start with pilot jets or needles.

Unkle Crusty*
 

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Discussion Starter #10
Well okay then. How did that help with the carb tuning?
I think I mentioned already, there is a good tuning guide for CV carbs online.
It does not start with pilot jets or needles.

Unkle Crusty*
if you have no experience in the matter then why did you post?
 

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No kidding.

if you have no experience in the matter then why did you post?
Interesting observation. You have not read many of my posts on the subject.
But to your problem. It is impossible to know how to adjust your bike over the internet. However by pointing you to a site that could help you, I thought might be, well help full.
I will admit to suggesting that many bikers do not have the patience required.
I am not an expert, but I have been around bikes for a lot longer than you. I have competed at various racing events, and usually did most of my mechanical work.

MY 79 XS11 runs fine after pursuing some carb tuning. My XS400 runs fine after a lot of carb tuning work. My other XS1100 is running after sitting since 1998.

Let us all know how you make out now that we know you are not very receptive to any input.

Unkle Crusty*
 

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Discussion Starter #12 (Edited)
sorry if I was rude Unkle Crusty, it is nice to have your opinion. I don't know what I got mad about anymore.
I have decided not to jet the carbs but instead I will be installing the airbox and am right now soaking the carbs in my pinesol/water solution. the #1 float was leaking pretty bad.

 
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