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Discussion Starter · #1 ·
How's it going guys, new to the site. Just picked up a 1979 CB650 project yesterday and wanting to see if anyone on here knows or can point me in the right direction with getting this carb tuned up properly. The bike was missing the airbox when I bought it, but I'm going to use air filters instead anyways. I found the factory settings for the carb with the airbox, but that doesn't really help with the air filters I'm guessing...
 

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Looks like someone was not very nice to that bike. I would recommend avoiding pod filters if you are staying with the original carbs. Find an airbox on ebay and use it, much less headache in th elong run
 
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Without knowing how it runs, looks like the thing needs paint, mirrors, a tail light, a better seat and new grips. Man it looks like someone rode that thing hard and put it away wet. Hopefully for your sake the PO put all their time into the motor, cause the outside looks rough
 

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2 threads you need to read first:

http://www.caferacer.net/forum/new-members-read-here/22280-read-first.html

http://www.caferacer.net/forum/tips-tricks/19639-pod-filter-thread-geeto.html

The next thing you need to know is that there is no magic formula to carb tuning....no standard jets or settings. There are way too many variables. It is a matter of making adjustment, riding it, doing plug chops, reading plugs, and making adjustments. Repeat as many times as needed. My methodology is to get the idle set first, then the mains for wide open throttle, then the needles for part throttle. You will also need to sync the carbs.... Probably a couple times during the process, as well.
 
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Discussion Starter · #7 ·
Thanks for all your Replies guys. So basically I'm learning this 4 carb thing as I go, its a fun and frustrating process as I'm sure all you guys already know that, having all your input helps a lot... SO firstly I took it all apart, cleaned everything thoroughly, and found out one of the jets was completely out laying underneath one of the floats, haha not sure how it got there. Put the jet back on and threw the carb back on and got the bike to fire up first try, IDLE was all jacked up, RPMS going high and dropping low and then back high again. And when i would turn the throttle it would bog all the way down and shut off, also it would only idle with choke fully up. Did some research and saw the cause was probably a clogged jet, took it apart and sure enough carb#4 and a completely blocked Jet. fixed that and then the bike would IDLE at super high RPMS and would idle with choke fully off. SO that was sweet that fixed it, wellllllllllll then it went back to not working again haha, except it would idle really high with choke off, but soon as i would give it throttle it would bog down.... DO you think there is junk floating around and clogged up a jet again? also how do you make the IDLE RPMs go down? i made sure the throttle is not being opened by that one adjustment on top of the carb as well..
 

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Discussion Starter · #8 ·
Without knowing how it runs, looks like the thing needs paint, mirrors, a tail light, a better seat and new grips. Man it looks like someone rode that thing hard and put it away wet. Hopefully for your sake the PO put all their time into the motor, cause the outside looks rough

yeah Cosmetically this thing will be 100% different when i get this thing to run properly haha, that will be the fun part, just need it riding first.. OUTSIDE is some mad max trash lol
 

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Discussion Starter · #9 ·
Without knowing how it runs, looks like the thing needs paint, mirrors, a tail light, a better seat and new grips. Man it looks like someone rode that thing hard and put it away wet. Hopefully for your sake the PO put all their time into the motor, cause the outside looks rough

yeah looking rough is an understatement LOL i won't be riding it around much at all once i get it running properly, she will be straight torn apart instantly.
 

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1982 Yamaha XJ650/1981 Honda CB650
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I'm rebuilding a bank of 1981 Honda CB650 CV carbs and noticed one of the two throttle cable pully fingers which hold the cable barrel has broken off and someone zip tied the throttle cable barrel in place. must say, they did a good job however i need a new throttle cable pully for a proper rebuild. Hopefully someone understands what I'm describing and can give me a direction of where to find parts. even a part number would help.

thank you
 
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