need help!!! idles high, carb issue!!

Ok, so i have a custom rat rod im building 1980 xs400, straight pipes two into one, cone air cleaners. it runs with the choke all the way out and idles high but once you put the choke half way or all the way in it dies. now i bought a jet kit and still cant figure it out. any suggestions or tips? ill post pictures once i figure that out lol thanks everyone

G'day Rusty,

Check to see if your cone filters are blocking any of the carbs air passages.

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Thanks for the reply pork chop! I didn't know the filters could block anything. What passages would they be blocking?

There are some pictures in this thread: http://www.xs400.com/forum/showthread.php?t=10766&highlight=pod+block

Ok I checked and there not blocked in any way. I got it to run and drive with choke all the way out but it idles really high and dies at half choke.

I am thinking Pilot circuit is good, the rest needs to be cleaned, including poking every hole with a skinny wire/wires.

Does clogged jets and holes effect throttle aswell as idle? Thank you for the responses.

http://www.amckayltd.com/carbguide.pdf
http://www.iwt.com.au/mikunicarb.htm
http://www.factorypro.com/tech/tech_tuning_procedures/tuning_carbtune,CV,lower_rpm_engines.html
http://www.mtsac.edu/~cliff/storage/gs/Mikuni_BS-CV_Carburetor_Rebuild_Tutorial.pdf

As you explore the links, the last one is for sukzuki, its is still the BS34 carb. which is explained on page 2.
Tobie

Does clogged jets and holes effect throttle as well as idle? Thank you for the responses.

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So I say Yes. One of the current problems we have is that current ethanol fuel standards. the fuel is prone to turning into syrup after 2 days, and with the narrow passenges, it will plug up and you will not know it. Which is why it takes 3 or more cleanings to get the crap out. The first link has trouble shooting on page 30. The second one is a graphic workign knowlegde of our carbs. like the last link, it states the 450 model is somewhat different. So take it in stride, and you should be able to find everything about carbs in here.

If you haven't seen this one, check this out
http://www.xs400.com/forum/showthread.php?t=10715 Willem bunch of how to's

has anyone used these carbs from mike's xs? https://www.mikesxs.net/product/48-9004.html

I have had a bunch of problems with mine when I get the speed up, it pops and loses power. If i let off the throttle it'll catch again but continue to do it over and over. Then when I come to a stop it idles really high then comes down periodically or it just dies at idle. I thought I found the issue with a loose carb boot, but that didn't fix. Then I found a hole in one of my floats, got new one, reset them. cleaned the carbs like 3 or four times and it ran great for a day. I'm thinking about just getting these carbs from Mike's

BTW I drive 76 XS360