Carbs possessed

[John]

My first question is, how do I tell if the slides are<br />installed on the correct side? Does the cutaway at<br />the bottom of the slide face the engine or the air<br />filter?<br /><br />My second question is how do I know what the correct<br />jet sizes are? I read on a post earlier that keyster<br />carb kits contain needles that have the wrong taper. <br />I'm not sure what carb kit was used to rebuild the<br />carbs, but I only have a pair of keyster kits on hand.<br /> Is there another brand that is better, that I should<br />use to rebuild the carb again?<br /><br />The bike is a 1977 CB77. The carbs were recently<br />rebuilt, though not by me. Last week, after taking<br />delivery on the bike, I got it started. Set the idle<br />(which wouldn't go much below 1,800, but it's an old<br />bike with new rings and pistons, I figured). I went<br />to take it around the block. It went okay for about<br />fifty yards. Then when I tried to open the throttle<br />more, it crapped out. The sound it made was sort of<br />like, &quot;gahhh hhhhhh.&quot; <br /><br />After struggling to get it started again, I brought it<br />back to my garage. It was running way rich. I'd heard<br />that if the slides are installed backwards, it will<br />yeild this condition. So I pulled the slides. The<br />cutaway was facing the air filter. I reversed them. <br />I also returned the clip to the middle position, as it<br />had been set at the second notch from the bottom of<br />the needle. After cleaning the fouled plugs, the bike<br />started on the first kick and held and idle at about<br />1,300. Throttle response seemed good. I put the bike<br />away for the night.<br /><br />When I returned to the bike next, it started right<br />away. I let it warm up and started driving. Throttle<br />response was very good. The bike ran well, but a bit<br />rich for about 2 miles. Then it did exactly what it<br />had done on the previous day. It made the &quot;gaaaa&quot;<br />sound and crapped out. This, I take to be fouled<br />plugs/flooding. I let the bike sit for a moment, then<br />started it. It ran well enough to get back to my<br />garage.<br /><br />I pulled the slides again and brought the clip down a<br />notch, to the second slot from the bottom. When I put<br />them back and started the bike, the idle went through<br />teh roof. I had to kill the engine or else it would<br />have redlined. At this point I started to suspect<br />that the slides were correctly installed the first<br />time, because I was actually able to start it without<br />the choke even though the bike had been sitting for<br />about 1/2 hour and it was cold out.<br /><br />I tinkered with the cables and the idle screw. I made<br />sure that the slides were not stuck. After this, the<br />bike began behaving as it did before I reversed the<br />slides (I did not return them to their original<br />position. They are in the carbs with the cutaway<br />facing the engine). Sometimes it would rev up to<br />about 4,000 RPM and hold there for a few minutes, then<br />it would just die. Sometimes it would hold an idle of<br />1,200. All this without me changing anything other<br />than the idle setting and the idle air mix screw.<br /><br />I will be grateful for any insight you've got.<br /><br />Thanks.<br /><br />-John. <br />

[jesse]

first the slot that is cut the whole length of the slide goes to the inside on each carb.look at the slide and you will see that on the bottom part there is a part that is cut away at the bottom that goes toward the air cleaner.also be sure that the needle retainer is firmly seated to hold the needle.move the slides up and down the carb bore by hand to check for binding.the old style with chrome plating were really bad for sticking.the newer ones solved the problem.it also sounds like your carbs need to be cleaned ,especially the low speed jets and passages.be sure to check jet sizes as some have been known to have been drilled out.

[costell2]

That sounds like what happened to mine. The slides were in backwards and the idle was crazy high. <br /><br />With mine, I have to adjust the idle mixture screws when the bike is hot. When it is cold, I have to turn them in half a turn and then back out the half a turn when the bike is hot so it does not run at a high idle.<br /><br />Maybe you have a different solution for me.<br /><br />Mike

[kustommusic]

Mike, yes the cutaway faces the air filter. I was thinking about the idle mixture screw,,when things are right a setting of aprox. 1 1/8 turn out from bottom is correct. If you are a ways from that you have problems! Have you checked to make sure the slides are in the correct carb? If they are swapped the idle speed screw will be inaffective. I don't believe I would consider the jets being &quot;messed with&quot; at this stage its way to messed up for that to be all that is wrong. The link to VJMC is where you need to go and find Bill Silvers FAQ page,it deals with carbs. some. Good luck! Steve Greer

[prima5star]

Keyster chime in...<br /><br />I bought the 2 cheapest kits off eba and installed them on my at the time daily CB77. My idle is a steady 900 or so cold, warm, in front of a sceptical audience etc. I don't think they included needles...<br /><br />Clean those carbs, use common sense, powers of observation and your manual.

[costell2]

I posted elsewhere on this site about starting the bike. <br /><br />My slides are now in correctly (V's towards the air filter) and the carbs are cleaned. <br /><br />My bike now takes forever to start. It useed to start up right away (first 2-3 tries) and now I have to kick it for about 15 minutes to get it started. <br /><br />I never had to use the choke before I brought the bike to a repair shop to fix the carbs and the slides (I know how to do it now). I think I could have done it myself if I new about the slides being in backwards. BEFORE I brought the bike in to the repair shop, I cleaned out the carbs one at a time so I knew it would be put together the same way, but they (slides) were previously put in backwards, hence giving me other problems.<br /><br />Now I have to operate the choke, but I do not know how it works nor what it does. Is there a reason why I have this sudden change in a bike? It used to start right away and now it takes forever to start. <br /><br />Quickly, here is a rundown of things that were done on the bike:<br /><br />Points cleaned and replaced<br />Timing set (it was way off)<br />carb slides switched (V towards the air filter)<br />Right carb polished (it was warped and caused slide to stick)<br />Clutch plates unstuck and lubed (froze when the rapir shop was test riding - they fixed for nothing)<br />New rear breaks<br />New clutch and break cables<br />New battery<br />Throttle adjusted (they said it was tight)<br />Splitter (for throttle) was replaced<br />New spark plugs<br /><br />I think that was it. But now I think I have to use the choke (which I never did before) to get it started. But i have no Idea what it does nor if what I am doing is correct. <br /><br />I turn on the key. I try starting the bike with electric start and or kick. No help. I move the choke all the way up and try for a while. I move the choke down a little and I try. I move it down a little more, no help. I move it down to half way no help. I keep going until it is all the way down and start moving little by little up. <br /><br />And I keep this procedure up going in both directions to find the right spot. Once I find the spot where it eventually starts, I try and remember where it is for next time. I try it again, in the same location and it does not work.<br /><br />I try the process all over again in different directions and I get nothing. <br /><br />I try and start it a couple of times in each position. I am pretty presistent with the bike. Cripes, I even use sweet talks to try and motivate the bike.<br /><br />How does the choke work or is there something else I am missing? As I said, it used to start on the first 2-3 tries, but now it takes a long time after I had all this work done on the bike.<br /><br />Please help me....<br /><br />Mike<br /><br />

[prima5star]

I suspect your float level is incorrect- fuel level too low. When starting there is not a lot of vacuum drawing the fuel in, once it fires there is a lot of vacuum so it will run ok once it's started. <br /><br />I think there is a procedure for setting the float level which you may want to look for... basically you are bending the little metal tab that acts on the needle valve and shuts off the fuel once the bowl is 'full'. The 'full' level is dictated by the metal tab. It's possible your needle valves are incorrect if the PO put the slides in wrong...<br /><br />I think you could test this theory by doing this the next time you try and start it cold: unclip a float bowl, turn on the gas for a second or two so the level in the bowl rises then turn off the gas, and reseat and clip the bowl. Repeat for the other carb. All you really want is an extra few tablespoons of gas in the bowls. Now turn on the gas and try to start with the electric start or what ever. <br /><br />If you store your bike indoors and it's not too cold you shouldn't need the choke at all. Mine starts easily on cold mornings after spending the night outdoors without the choke! Well, it used to when I rode it frequently...<br /><br />Send me an email if you need more details.<br /><br />Matt