Mikes keihin carb kit

Thanks pamcopete---- that makes sence. My right carb cable has slack all is good. The left carb cable slack is all the way in and there table has tension on it. thats not right. I really do not want to take this carb appart, its brand new. I may have too, that cable needs to be relaxed---
 
sick nick,

You can screw the elbow in further for more slack. This can be done with the carb installed. Just twirl the elbow in deeper. Make sure that the cable ends are in their recess in the elbows as well.
 
All good stuff, the cable pipe elbow is threaded in all the way. the adjuster is in all the way. I took both slides off the carb body, unthreaded the joining tube where it goes from 1 cable to two, looking inside my cables are set in the recesses. reassembled and still the same. i noted the cable adjusting screw that threads into the formed tube elbow is not threaded as far us as the right side. I need to thread the lock nut up farther so i can screw the adjuster in more. They are clearly not threaded the same. I am done. Looks like a call into father Mike's xs for a possible cable swap or more there will be no gas to these virgins today thank you for the quality advice pamcopete--
 
With both carbs mounted, both idle screws backed out and not contacting the slides, both cable adjusters in all the way, I have no free cable movement. I can only get cable free play if I screw in the idle adjustment screws and raise the slide.
This could possibly be ok if I knew how many turns in the idle screw needs to be to get to 1000 rpm on each cylinder. Finally ending up at 1200 rpm final set point. From what all I read, these cables should have free play with the idle screws NOT contacting the slides. Am I correct? does anyone know the average amount of idle screw turn it takes to get to the final set point?

I can determine that by putting gas to these carbs and running the engine, but if There is an issue and they need to go back, better to be virgin assemblies than to have them classified as "used" via adding gasoline to them Any thoughts would be appreciated!
 
sick nick,

Be sure that the slack adjuster on the throttle cable on the handle bar is backed out all the way as well.
 
My idle screws are fully backed out. My cables have no free play. That is my fear. If I need to turn the screws in to raise the slide, then I will have cable slack. I will have no problem, If the slides need to go lower to lower the idle then I am screwed. The Cables being just too short will not allow the slides to go as low into the carb throat as it could if there was more slack. If I put gas to the carbs and I lower the idle I will not be able to, then the carbs will be considered used & I am sure I will have a hard time returning them. Mikes wants me to return the cables for inspection. If I did I will return the entire kit as it.

Do you know after the initial srew setting to just raise the slide up evenly how much the screws need to go in to get the engine to idle at 1200?

What is the black know for on the top left of the carb for?

I cant believe there is no paperwork with this kit. Nothing. I am a diesel guy that runs harleys, this 650 is giving me a run here @$#* !
 
racerdave said:
Do you have free play if the cable is disconnected at the throttle {handlebar end} ?
Click to expand...

The cable is disconnected from the throttle. The adjusters on the carb cables are all the way in and the curves cable guides are threaded all the way in. The slides are being held up by the cables. Does anyone know how much on average the idle screws need to be turned in and how much the slides should be raised? If I have to raise the slides I will be ok if it idles too high I am screwed. I am about to give up. Mikes has no tech data on these carbs I think I should just return them as new and let mikes figure it out.

Posted via Mobile
 
Yes food thought. I checked that. I unscrewed the cap and got into the spring and the plastic seat. Both cables are set correctly. The bottom line is the cables appear to be min 1/8" too short. I just wish I knew if the slides were up enough that they would have to be raised more to meet an idle slows of 1200 rpm. If so I'm ok. But I don't know if that is the case. I I start the engine and it idles too high I can't lower the slides the cables are holding both slides up. I have no choice I have to send them back. I am out of options.

Posted via Mobile
 
Wow, I wish I had read everything on here before wasting so much time on these Carbs!!!! I've read and re-read everything so many times. I have a tx650 72 ,pipes slightly smaller. The bikes running rich everything is set to the leanest possible setting (pj,mj and needle clip)mixture screw at 1/2 turn(only way it would run). The cable is set up as per instructions given, along the top of the engine .Checked valve clearance..all good. Still RICH!!
Do any of the Aussies on here know where to get leaner needles in Melbourne, Aust ???? I would prefer to be riding then waiting on long arse postage.
Cheers
 
Last edited:
Need some help with the 32mm Keihins... float vent is leaking every five seconds or so and will not stop. Float appear to be ok, but am at a loss. Any suggestions anyone? Thanks.
 
Phoughteling... I had the same issue it turned out to be such a shitty casting inside the float was hanging up on inner casting of the carb. Had to be ground out very carefully with a dremel. Now its not leaky at all. Mine is still running a little rich after a lot of work on these supposed ready to bolt on and go carbs. I will however say once I get the cable hanging up problem fixed this bike will be dialed in pretty well. It's faster for sure.
 
Thanks for the help. It seems like I hear a lot of the same problems with the Keihins over and over again. I have a pair of 32 Mikunis I think I might give a try.
 
Well I installed my set and had a hung up float as well but it was a quick fix and they are working great. Great throttle response, but i would rather run a dual cable throttle to avoid their split cable which is very finniky about it's position. :shrug: You can see once the chokes are off that I have to fiddle with the cable to get it from being hung up. Keep in mind the cable is not fully secured yrt and I'm sure it will be better once it is.

http://i8.photobucket.com/albums/a46/mrkil2/12f161e7.mp4
 
Plugs look good however I haven't taken it for a run yet. When it's ready to eoll I will do a plug chop to get a true at speed reading.
 
Adrain, I have a suggestion. make certain you combustion chambers are healthy prior to trying to tune the bike. Is the engine a virgin? Any recent engine work? Try these tests if you are not 100 % sure of the cylinders condition; remove the spark plugs and do a cylinder leak down test. Bring each cylinder up on its compression stroke to top dead center. The get the transmission in its highest gear. apply 150 psi to the cylinder and listen for leaks from the intake, exhaust, and crankcase breather. Get set up and do this with the engine hot. Then after that test, rotate the engine and lower the piston to its center stroke point and do the test again. Holding the bike in hi gear helps keep it still. The pressure in the cylinder is trying to rotate the engine. you may need help holding the bike from rolling forward with the pressure in the cylinder. before you make any judgements on the carbs you need to be sure the cylinders are healthy. I have the same carbs just installed and they run awesome. Not rich at all. But I just did a valve job and new rings. Another quick and dirty way to test is set the engine at 1200 rpm. pull one plug wire off. What is the RPM now? My engine runs at about 750 rpm on each cylinder. Also, starting the bike cold, measure the exhaust temp from each cylinder cold and as it warms up. Write it down every 30 seconds while the enrichners are pulled up. Warm it a bit, then take the bike for a nice light short loaded run with out much stopping. measure the temp again of the exhaust and temp of the pipes close to the head. determing if both cylinders are contributing equally. THEN you can start talking jet size. Also, what spark plugs are you using? Do you have the standard origional ignition system?
 
update on my carbs: I sent them back to Mikes. They were returned to me and the slides were now bottomed out. The cables must have been changed. What Mikes did I do not know. I installed the carbs, and the bike performs awesome. I am very pleased with this bikes performance. I have the hi output electronic ignition, coil, and recomended plugs. Idling at 1200 rpm i do have freeplay in my throttle. I have no way of knowing if the origional cables were too short. All I knew was I was not going to start the bike with the slides held up. I do think they were higher up un the vencuri bore then now idling at 1200. So I am glad I sent them back and Mikes did what ever they did to them. What I did change though was the 4 mounting screws. I went on line and ordered slightly longer allen screws to mount the carbs. I wanted to use a washer on them and the length mikes provided scared me. I thought they were a bit short. The new hardware costs 5 dollars shipped to my door and the new grip length has me satisfied. These bolts are not ever going to loosen up and possibly damage the threads in the head. Life is good---
 

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