serious issues with the mikes carbs.

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malloym

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first off I want to say that I read the carb guide, did a search and read the mikesxs carb thread. my bike won't run worth damn with these carbs and I think I got a defective set.

here is the deal, I got a stock 75 engine, 2nd O/S pistons, pamco ignition and free flowing exhaust. (custom) at first i thought is was my PMA setup, so I hooked up a battery just to try to tune these things at idle..

issues.... bike is running extremely rich, already fouled out 2 sets of plugs just idling. I hooked up the factory tach for tuning purposes and with the air screws set at 1.5 turns out the bike will idle at 2000 rpm. I tried the dead cylinder method that pete listed and when I remove either vacuum barb plug the idle will shoot to 3500 rpm. i checked the throttle cable and they are not hanging up.. also I removed the pod filters and i'm getting fuel vapor coming out the the intake side..

i just installed another set of plugs and within 3 mins of idling they are completely black.

i thought these where suppose to be in the ballpark to begin with.. I don't even know where to start.

I need a plan of attack for these carbs.. any help would be great....
 
what carbs? The carb guide adresses the 34's and 38's found stock on these bikes.
Mikes xs sells those now? it would be great if they did. last I checked, they didnt.
 
iyou said you read the carb guide.
now that we are clear on what you have, sorry to say. I cannot help you. I think teecat is running one on a dual runner intake. sorry if i jerked you.
 
Those carbs could be called defective but that would imply that mikes carbs are ever very 'effective'.... But seriously i would guess two sizes down on the pilot with the air screws at 2.25 turns out. Sync the carbs, try to get your hands on a manometer... Make sure your carb boots are air tight at the gasket and the entire clamping portion.
 
anyone else... should I check the float level??? I recall reading that they should be at
19.5mm..

also, wouldn't a vacuum leak cause a lean condition? happens on EFI... this really pisses me off. I'm a merecedes-benz master techinican that works on 100k cars all day long and I can't tune a set of carbs to save my life.
 
Being that the kit comes with three sets of jets, have you gone down to the smallest one? Have you checked your timing and gone through the routine adjustments like valves, cam chain, etc? Have you checked your compression? I'm just thinking out loud here.... A rich condition could be caused by your float height, however I have not installed the set of PWK's I have and thus notmhad time to read-up or dick around with them.
Jets are cheap, if you are running the smallest jet, have you considered ordering the next two sizes smaller and giving those a try?
I just wanted to make sure you read over this thread:
http://www.xs650.com/forum/showthread.php?t=3446
 
well, it's really quite simple, if time consuming.

plugs black? go down jet sizes for the pilot. how many sizes? who knows. where ever you are, get 5 increments down. ie: if it's 135, get 130, 125, 120 etc. get 5 sets. when you figure out where it's not blacking the plugs anymore at idle - then you can start on the mains.

there *may* be a guide to sizing - i don't know those carbs, so i have no clue.

check the jets in them to make sure they're what Mike's says they're supposed to be first, too.
 
Yes, malloym, you should check the float level on any new carb, and I don't know how many times I have to repeat it. Also any new carb from any maker (but especially the Chinese) should be stripped and cleaned before use; even real Japanese carbs have been know to leave the factory with machining debris in them. And by all means read mrriggs' excellent thread, then kick yourself for not reading it before you bought that junk.
 
OK, Joel. In all sincerity, here's the most helpful advice I can offer. Don't throw good money after bad. Do a proper job on the OEM carbs and chalk the bad purchase up to experience.
 
My father (a factory trained Harley mechanic from the early 80's), looked on Mikes and asked me about the PWK kit. If this guy, who DEFINITELY knows his stuff about bikes, gets fooled by the kit, I can't fault anyone else for doing the same. The price is nice and the description touts it as a bolt on installation with jetting that's right for most installations, and that the carbs will make your bike run awesome. Now we all know that we want that. He may not have researched his purchase, but so be it. Some people are too trusting.
 
thanks fella's... I am kicking myself as I had a perfect set of BS38's that were working fine. I got sucked in by the hype and it was an impluse buy.. i'm going to go back to the basics and strip these things, clean, inspect, and go from there.. I do have a feeling that I will be contacting oldschoolcarbs in the near future as I have my doubts with these PKW's

I'll update and see if I can find a solution.
 
I was surprised back when I read mrriggs' thread, because Pete and Travis, and joe wiseguy, thought highly of them in this other thread. Some people hate on Mike and others smooch him, and they're pretty consistent with it. So who knows. LOL. I don't know how much bias for or against Mike is in these reviews.

http://www.xs650.com/forum/showthread.php?t=3446
 
As the old timers say here in So Ill, "Them that won't hear it's gonna feel it." You can get what you pay for, but if you buy cheap enough you'll get a whole lot less.
 
xjwmx said:
I was surprised back when I read mrriggs' thread, because Pete and Travis, and joe wiseguy, thought highly of them in this other thread. Some people hate on Mike and others smooch him, and they're pretty consistent with it. So who knows. LOL. I don't know how much bias for or against Mike is in these reviews.

http://www.xs650.com/forum/showthread.php?t=3446
Click to expand...


You read my mind. Now get out of my brain!

I have this carb kit that I picked up used for super cheap here on the forum. The guy just couldn't get them to run right, so I figured, what the heck I'll give them a try and see what happens. I also have a set of lectrons and VM34's that I'll be testing as well.

It's strange, because it seems Travis, Pete, etc have had really good luck with these carbs, and I know others that have had the same experience, but at the same rate, these bad reviews are coming out of the woodwork. Mr. Riggs says he likes them after he got all of the bugs worked out and they seem to make his bike pull harder. After reading all of his info it seems that these carbs may be a good place to start if you are willing to put in some testing and man hours to get the kinks worked out, but a bolt on ready to go deal, I think not....
 
I have had good luck with the carbs (after sorting out throttle cable issues), but my experience is only with installing them and a handful of test runs. I've only had that bike out twice since the winter and both times it started right away and ran well.

malloym, I would keep playing with the throttle cable, remove them from the slides all together and you should have no problems getting your idle down below 1,000 and doing the dead cylinder method. Once you have the idle down and it running well, hook your cables up again and see if anything changes. Also make sure your slides aren't sticking.
 

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