I got a kick out of this video! I enjoyed this so much, I watched it twice on my smart TV. I'm currently in the process of restoring a 1985 Honda CB450SC. I have touched, replaced, cussed, fought, cried, laughed, drawn blood, over this motorcycle and the very last thing I'm doing is the CARB rebuild! Fuck-in-A! What a piece of luck on my part, to run across this "how-to" video! You ROCK!, Todd!!!!! I've been about 3 years in this process replacing, painting, splitting case halfs, seals, bearings, gaskets, fucking ordering shit off of eBay etc! Lol! I'm an old retired Army Apache helicopter mechanic and decided I'd give it try. It sat in the garage literally in baskets as I was preoccupied with my sweet wife and her cancer. She passed Aug 2019 and I've used this rebuild as kind of therapy to keep my mind and time occupied. In any case, I fucked up the set of carbs that came with the bike by being a douchebag and following a RU-vid video preaching how great Mureatic acid was to clean carburetors, haaaaaaa, nope not so much! They looked great after soaking in a premix for about 5 minutes, but the next day they looked like they were covered in napalm. Anyway, I digress. You've helped me out a bunch. I managed to pick up 2 sets of these carbs here in Texas and am in the process of cleaning, disassembly for rebuild. Thanks again "fucker and fucketts!" You've given me renewed enthusiasm! Respect! Russ
back in the day when i was young, there was no youtube to learn from others. I was lucky there was an old Chicago outlaw who lived next to me in Alabama. He taught me a bit about working on those older bikes. So youtube can help many if theirs people like you to help them. I say thank you sir for being a good dude and making your videos to help others.
I inspected the needle under a magnifying glass and it looked good and the little springy push rod works also. The o-ring in the needle seat I am not sure of, that sounds like the whole carb has to come off for that and its hard to see up there. Anyways, I took a little air pressure and blew up where the needle seats. put it back together and it is not leaking right now, but it didn't leak the last time either until it started again. I hope it was just a piece of crud. Thanks for the help.
The floats are the white thing .. The slides (cylinder with big disc on em) lift according to vacuum to keep the airstream over the jets at best velocity -- those are what makes it so you can slam the throttle out instead of having to follow em out like we had to with the old mechanical slides carbs
should be one turn on each - generally I'll set em to 1.5 turns then pick a side, adjust the mixture till the rpms peak. then back off just a hair, shut it off, set the other one to the same number of turns. THen give it a run around the block, park it in front of the fan, hit it with a temp gun (measure at the first bend in each exhaust pipe) and match the second cylinder to the first
I did the petcock today. It looked pretty good, but had already did it about a month ago. So I drained the fuel tank, and boy, was it full of crud! That couldn't be helping anything. I got all the loose stuff out, but will clean it better and coat it in the fall.
Dont sweat the shaft drive - That black Goldlwing of mine I've replaced the dampeners in many times but the pumpkin is still passable after 1.3 million miles - I'm a nut about changing my oil every 1000 miles on the 1000 (or at least within 50) and my gear oil every 2000 miles - I'm just now ready to put the 4th knuckle/u-joint on the front of the shaft where it joins the output from the engine - still on the stock shaft assembly 'bout my 10th set of seals though
these older bikes and carbs is all i have ever worked on, i don't know what i will do with my newer 2005 Honda, sense i don't know much about them. But i have read through the book i bought to get an idead how they are built. I am lucky it is carb fueled. The newer bike is also shaft drive. Seems like easy dealing with it. But dont know what the cost will be for shaft drive, unlike the chain drive was always pretty cheap.
little crud getting in there from an old fuel line maybe? Forgot to tap it a hair with the plastic end of a big screwdriver as the bowl was filling? (SOME Kehins if the float is dry and all the way down the needle will get stuck at an angle and that's the only way to get it to line up right and go up that first time)
o-rings in your needle seats in good shape? rubber tips on the needles NOT grooved? (if they are replace the whole needle - temporary 'get home' would be to soak em in mineral spirits an hour before putting em back in and getting gas on em immediately while they are still soft). Little springy pushy rod thiggy at the bottom of the needle moving in and out like it's supposed to? {Response by Katyia not my dad}
old mechanical slides or twin cammer all metal vacuum slides? - either one can be unstuck with VERY gentle pressure and some hilco lube -- use a BRASS rod or screwdriver though - NO HARD METALS -- takes forever but at 90 bucks a slide they are worth saving if they are not scored -- VERY often they will lock back up on the shelf if not properly preserved
Bikes are a lifelong hobby since I was 6 .. I installed radar mostly but did some oddball broadcast and surveillance equipment too ... I know I cant express what I'm doing good... That's why I try my best to keep where the camera can see what I'm doing.. Hopefully folks get it between seeing and hearing
I drill out the plugs and at bare minimum check to see are they still set right (also if they have the o-ring and washer you dont want to soak those) 850gl you have to break em apart - those seals in-between are a: 31 years old and due for replacement and B: old rubber that will get eaten up by carb cleaner
This was an awesome video, thanks for sharing! Have any tips for setting the idle/slow mixture? The factory service manual says to set initial to 2.25 turns or whatever (you said a hair under 2), then set idle to 1200 revs, then set one side to fastest RPM, back it down to 1200, then set other side to 1200 RPM. I have had trouble hearing the "fastest" RPM because it only varies like 50 or 100 RPM and 1200 RPM is hard to differentiate from 1250 RPM! Any tips for this? You said you don't set them by fastest RPM like that. I think I have the issue you were describing where it's running on one sometimes - at least until the mains kick in. I have an '82 450 and an '85 with these VB22's and the problem I'm having with both is at around maybe 30% throttle the bike is stumbling bad, but then after the slides open it's perfectly fine. Slides aren't sticking at all. Raising the slow jetting didn't do shit, carbs are spotless on the inside, happens on 2 different bikes with 2 different sets of VB carbs, I'm thinking it's ME who is out of whack... I need to get this mixture dialed in!
Hi man, I'm raphael from Italy. I've a VB Carb like your, mine it's a VB37A and I would like to take a part original air filter and put two pods K&N. For sure I've to change the main Jet, but can you tell me if I will have problem with the pressure piston?
You can use Accels (140404's if you still have points - 140403's if you are on CDI or a dyna box) They are either lazy or should not be in the business.... 150's dont sound high -- but only if you are putting in matching needles at the same time -- 130's are the edge of what you can do without dropping your needles a clip (those you can set by your mixture and it will be a hair rich but not OPEC be smiling rich)
I am rebuilding a set of these and it seems that the floats are sitting way too low and may not do anything with stopping the flow of fuel. The other carbs I have rebuilt, the floats have a slight bounce when sitting on the gas inlet needle valve. Since they are not adjustable, what can you do? Also, how do you know for sure if you are supposed to have the little rubber plug in the hole next to the main and pilot jets? 1985 Nighthawk 450.
Love your vids. You make this shit fun.. I've just bought an 82 GS850GL with Mikuni's and need to do a good carb clean. Do you always break them apart or clean them on the rack? I've seen vids both ways. And the air mixture screws, should I drill out the plugs or leave them alone?
I generally use 600cfm square bore Webers - just gut the carbs, put sleeves through em, and that plate on top that holds the air cleaner... yahh plate of aluminum makes a perfect base for a square bore. -- The spread bores it's too small of an engine to get any low end out of em -- The 700 Square bores dog when you goose em - The 600's are about the best match for the engines
Great video! Thanks for taking the time. I'm doing a 82 cb900f now. Any good recommendation for setting mixture beyond the 2-1/2 turns out? They ranged from 2 turns to almost 3. The carbs have been messed with before lots of stripped fasteners and gooey air cut off. Again love the videos!
If you mean pods .. I DO NOT recommend them for this style carb - your slides wont last 6 months without proper lubrication -- These carbs depend on oil coming from your pcv in a vapor into your airbox to keep them lubricated... Bikebandit (com) sells em.. but you have to oil em every week or you'll be replacing those 90 dolla apiece slides every few months (or have a bike that runs good 2 days and just gets crappy after that)
I have a set of VB 42A's off a 81 CB750K. I'm new to carb rebuilds and really appreciate this video. I'm in process of rebuilding mine. I saw instructions detailing exactly how to set the choke and adjust some fast idle arm that aren't real clear in my opinion. Doesn't the choke lever supposed to push up to open throttle when choke is open fully?
depends on the linkage but yes if the choke is fully CLOSED (meaning you pulled the knob and closed it) it should advance the throttle a little bit - The best comp diagram I can point you to is the one for the CB450A - use bikebandit .. that's a 1/2 rack of what you have in front of you ... (linkage wise) -- but the diagram is much clearer for the linkage than looking at the one for a full rack
Thanks for your quick response, I appreciate it. What did you polish those diaphragm covers with, they look really good. I know some people sand the aluminum then polish, is that your method? I have tried the marvel mystery oil on the stator cover but it didn't do anything. Small black spots in the aluminum, is that the patina?
it's pits that the oxide moved into and filled (shows where you still have to polish with a buffer) .. On the carb tops I use Tripoli, then white cheap Harbor freight polishing compound - then instead of red I use a dry wheel - Wheel in question is an old bench grinder with buffing wheels instead
first always kick ass videos man, second I was searching for you input. I know that your video mentioned the af screws being set, but I was looking for the reassembly of them. I know there is a spring, and a metal flat washer on the af needle/screw. but is there also a black little oring, on top of the whole assembly? spring, then the flat washer, then the oring? I tried to find your Facebook. thanks again!
I've been playing with hondas, Kawis and an Ariel lately All Kehin and Bing but depending on the bike I have vids up of both kehin and mikuni coming in or out. most bikes are generally the same as far as how.. be specific on the bike and if I have one close enough to the front I'll pull one out
Any tips on adjusting the pilot screw on a 72' CB450 if the bike won't turn over and you don't have a carb gauge? Had it running then made the mistake of trying to adjust it when the left sounded like it was running lean.
ok well got my bike back got my round tops on, when i went to put them on the old ones fell of in my hand that shop didnt even tighten them up on the carb side, anyway bike runs good now i just have one lil thing to fix when i rev it up seems like everyothere time it takes it some time to come back down to normal idle do i need to readjust the idle air screws or could the mechanical advance need oiling
I have an 82 cb450sc. fuel is leaking out the overflow tube on one carb. I took the carbs off and cleaned them and then I switched the floats and put them back on. The same carb still leaks with a different float. The needle valves looked good when I inspected them, but maybe the needle is not working properly. what should I do next? Thanks.
hey i have a question for you im loseing faith in the shop i took my cb 750 chopper to for one they are saying that you cant use accel coils on it with it has an the main reason it took it there was for the carbs needing jetted it has the keyhole style carbs they are gona try putting 150s in it does that sound high they dont wanna sim the needle im ready to just bring it home
What a big help... can you help me on something Dawino6260? My bike is a CM450C. There are 2 size of jets (main and secondary main probably... I'm so a bad rooky in mechanic!!!). I unscrewed them off to clean everything and didn't checked de size of the jets (holes). Wich is wich and where they go??? Thank you...
I have a cm 400 with vb 21 c carbs with 112 mains and 70 idles. I also have the a used set of vb22ga. with 115 mains and 72 idles. Can i just throw these on and what might be the challenges? If not can I change the mains and on the vb22ga with 112 mains and 70 idles? or the opposite take the vb 21 carbs and put 115 mains and 72 idles? i would be changing out the rest as well? whats the downside of any of this or other problems? last what the fuck do you mean money from the videos? you are giving it away to good causes. Thats great!!! Is there like a minimum or what? its a real good video. thanks from A F___R from canada
Just got a set of carbs back for my CB750, Kehin type. Fuckin' slides don't move when I reach in to lift them... Guessin' I got screwed on these "cleaned" carbs.
Yeah, I've tapped that thing til' i'm blue in the face! Doesn't seem to make a difference. I'm gonna take the bowl off again today and check it out. Wish it was easier to get the bowl off while the carb is on the bike. Also wish it was easier to get the carbs on and off. Those rubber boots make it very difficult. See what happens, this is pissing me off!
My best ol friend,hated these carbs/he could build a engine from parts,Lectron flat slides are the simple fix for all this garbage kinds,they work really well on kow 900/100/and punched,out Zukes,most nameable 1983 GS 1100,or Kaw 1200.you really are funny,but you forget to talk when you got shit going on,hey we are still here watching the well behaved bike,playing sit.Thanks for this weird info,you come up with.Were you a mechanic in the servive???
