cb500 jetting question????

S

supercafe

Coast to Coast
hello there, just picked up a 1973 cb500. which i thought was a cb500t, its not a twin.
any way, i want to put pod filters on the bike, and i was told that with the cb500 fours you don't have to do, do you have to???????????????????
also, are the twins better than the fours?????
thanks for the info,
later.
 
CB500t was only made for 2 years: '75 & '76. If you do anything to the engine on either end (input or output), you will most likely need to rejet. Removing the airboxes can make the engine run lean. You will feel less power with stock exhaust still on. If you remove mufflers or baffling, it will remove back pressure which in theory will make it run even leaner. You can adjust by running the choke half open but it sort of defeat the purpose of running pods.

Put on pods, do something with the exhaust, do some plug checks, research about rejetting. Lots of info on here!
 
This might have some relevance to your 500-

I just rebuilt my CB550 (1974) carbs, and also installed the Uni foam air pods (K&N will not fit due to the proximity of the frame tubes aft of the carbs) I purchased 115 jets to replace the 100 jets that were in the bike.

The bike ran great with the old Kerker the PO had installed with the 100's but when I "podded" I went to 115......................the bike runs super strong.

Air/fuel mixture screws are backed out 1.5 turns, and I balanced hillbilly style by measuring the slides travel before re-installing the carb bank and varying the spring tension on the actuator arms.

I will fine tune very soon, but for know, she runs like a race machine, and the plugs look perfect.
 
hey man,
thanks.
is yours a 500 four??
i do have the 100's in now, so i think i'll get some 115's, did you do any thing with the pilots or any thing else???
so in the end it runs good with out jetting, but runs and pulls better with the jets.
i am still undecided if i want to run pods or stock box!!!!
but now with some one else with the same bike and with the same set up i want, i might lean tawards the pods.
thanks again,
later.
 
Yes, it is a CB550 Four, and I need to take some pics of the carbs, as there are some little tricks on getting the 0-ring to fit perfect on the bowl/body junction.

I retained all stock carb internals except for the 115 main jets, and I can start her with flip-flops (kickstart) on one push in the morning.

I purchased the OEM carb rebuild kits from Fleabay, and just got the gasket/o-rings packet, not the kit with all the jets etc.

The throttle response is "right now" with the pods, and it fired on the first kick after the complete carb overhaul.

My jets were push in style, and are retained via the spring armature that contacts the bottom of the bowl. My carbs were in fantastic shape, and a little cleaning and polishing got them looking brand new.

You must bend the choke lever outward maybe 20-25 degrees to clear the pod base, but that is easy, just use needle nose pliers, some masking tape to prevent scarring the lever, and with one mellow even movement, bend the lever. Works perfectly!


Pulling the carbs is easy, but make sure that you find the third fastener inside the stock airbox so that it comes out, feel around towards the inside front of the box towards the bottom and you will find the fastener!
 
hey man,

the carbs on this bike were all gummed up, needs a good cleaning, but other than that they should be alright, i think.
mine are screw in jets.
the air box assy was already out, so very easy to remove the carbs. what recomendation on cleaning the carbs, and do you have to remove the whole linkage on top to get the sliders out???
i haven't got the carbs off the parts bike yet, but it had the 4-1 exhaust on it so i hope it has the 115 in them, or at least 110.
how much were the pods you bought?? and were did you get them??
same with the carb o-ring kits???
oh do you have any pics of the bike up on the forum?????
i need to get some of this build up here soon, but i am not convinced if i should keep it cafe or make it into a brat????????????????? big question, what do you think brat or cafe?.
some questions on the ride of the bike, how does it ride?? how is the torque and power on these bikes??? and finally how is the handling??
do you have stock shocks?? i have the manual and it has a performance section and it says i can put a one inch spacer in the frt fork assy between the top filler cap an the spring, and this is supose to stiffen up the frt.
any way, sorry for the questions, but i have not had a cb500 before and there are'nt to many that have the 500/4 here.
thanks, man.
later.
 
I have a '78 CB 550K (550 Four).
The engine/carbs/exhaust are all stock except for the pods I added.
I got the bike as 2 boxes of parts and have been slowly putting it back together for the past few years.
My bike is almost 100% now but it doesn't run w/o the choke pulled, so I'm pretty sure I need larger jets.
I have no idea what jets are in there now, I'm pretty sure that its whatever came stock. The carbs were just a big block of gunk when I got 'em, now they look and work great... except for the mixture.

I love the look and feel of the bike, but its never run well enough for me to actually ride it.

I have been able to ride it around a parking lot before by using the choke plunger as a throttle, that was fun :)

http://www.flickr.com/photos/schjlatah/3258747743/
 
hey,

nice bike there, would look awesome with some shorty shocks on the rear.
make it look like a brat/bobber. any way, normally with the bike running on the choke alone, the pilots are either clogged or to small.
either way it does sound like a jetting problem.
do you have a post in this forum??? if not get one up on that ride, it would fit right in here.
thanks,
later.
 
The pods came from an Ebay vendor, and were something around $50.00 or so, the quality is fine and they are made in the USA by Uni.

O-ring kits came from another Ebay source, and everything is straightforward, but when you go to run the o-ring into the bowl's channel, at first you will swear that the o-ring is too long, and you got a bad kit..........the secret is to push the o-ring all the way to the outside of the groove, and follow the "corners' with the ring contacting the outer groove wall- they then fit exactly right!

I completely stripped my carbs to include the linkage assembly, and it can get tricky because there are woodruff keys on the shaft, and the shaft needs to be pulled out to the LEFT if you are sitting on the bike so to speak. The throttle return spring has a lower grooved pin that is retained via carb bodies 2 and 3, so don't lose the little guy.

You can get the slides out without totally stripping down the linkage, by pulling the carb bodies from the main plate, and removing the top fastener you see after you take the carb top caps off, the pivot arms come right out from the sides.
 
I am going to make mine a cafe.

I am doing only one thing at a time when it comes to mods/service so I don't end up with a basket case (been there, done that). I got lucky with a tight strong bike, so my problems are minimal, and I ride it almost daily.

It has lots of low end grunt, and is extremely fun on tighter "slower" roads, but hitting 70+ winds the bike up....I am considering adding a tooth to my countershaft sprocket to get some more top end. Ideally, I would like to be in 4500 to 5000 RPM at freeway speeds, and not howling at 6000+ like it does right now.

My Clymer manual says 10-30 for the forks in one place, and ATF in another, anyway, I slapped in some fresh 10-40 (195cc) in the forks, and wow, what a difference! The old oil was totally shot when I got the bike, right leg had ATF, and left leg had old stinky dead ass motor oil.

She handles great, but with some clip-ons, I am willing to bet she really handles awesome, and the cafe conversion has me very excited. I am 200 pounds, and to bang 70+ I gotta lay on the tank, so the cafe conversion should suit the bike perfectly IMO. For cruising though, it is a really classic looking ride, and turns heads. Either way you go, it can't hurt, the 500-550 CB's are strong little girls.
 
cool man,
thanks for the info,
it looks like a tricky process, but i'll get it done.
i still have to get the other seat of the parts bike. got the tank off and thought it was going to be a throw away, amazingly the inside is spotless, not rust, nothing, pretty much brand new. same with the petcock, i was amazed at this, the bike is almost 40 yrs.
so i am hoping the carb are in the same shape, here's to crossing fingers.
any way, thanks again.
i'll take some pics of the carbs when they get off there.
later.
 
i believe that i am going to stay with the cafe, i installed my new to me 4-1 and it looks sweet.
with pods there even sweeter. i have the original seat pad and pan, the PO put on a new wrap straight from honda, so it looks good, but i might cut down the foam at the frt section, and leave the pass part of it, so the pass part looks like the hump. should look alright.
i think i with you on the rpm's on the hyw. 6000 plus is howling, and fuel cost would be more.
we'll see where mine is when its done, if it is 6000 or better, i'll be doing the same.
thanks
later.
 
motorbike1001.jpg

motorbike1004.jpg

motorbike1008.jpg


Soaked the carbs in cleaner, then scrubbed with a toothbrush and dish soap, then re-blasted with carb cleaner. polished top, and bowl, and rebuilt.

Disassembled the linkage, oxide blasted all the steel, then put the parts in my Manganese Phosphate bath (military flat black coating) and then soda blasted the linkage plate.

Installed pods, and she fired on the first kick.
 
Hannibal Smith said:
It has lots of low end grunt, and is extremely fun on tighter "slower" roads, but hitting 70+ winds the bike up....I am considering adding a tooth to my countershaft sprocket to get some more top end. Ideally, I would like to be in 4500 to 5000 RPM at freeway speeds, and not howling at 6000+ like it does right now.
I am 200 pounds, and to bang 70+ I gotta lay on the tank, so the cafe conversion should suit the bike perfectly IMO.
Either way you go, it can't hurt, the 500-550 CB's are strong little girls.
Click to expand...

Your not revving it even close to hard enough.
My 550 would do 82mph in SECOND GEAR (@13,500rpm ;D)
Still have it, (since June 1977)
Hasn't been ridden since it hit 106,000 miles (mainly because its in Britain and I'm in Florida)
Heres pic rolling over to 100,000 miles
 
hey guys thanks,
bike looks good, those pods are short, they look great.
what is this soda blasting every one is talking about??? is it sand blasting??
i don't want to paint these carbs, like on my cd175, just a hassle.
but i do want them to look clean and new looking.
are you going to paint the tank an covers????
looks like your going for the brat style????
either way it looks good.
thanks, again for the pics. i'll have to get some up on mine.
later.
 
I am going Cafe, that bike is less than week old! I got it like that, non running for 500 bucks on Craigslist, within an hour of getting it back to the shop, I had it running strong. Got the jets and pods, and while I was waiting got the carbs ready for a rebuild.

I have already rebuilt the front brake, and have new fork springs inbound, so the forks are next. After the forks, I will build the wheels with stainless spokes and aluminum rims, then get the exhaust done.

After that, comes the tank and seat, and a final teardown and powdercoat of the frame. I will make my own clipons, triple clamps , rearsets etc. while this is going on. The goal is to minimize the bike downtime, and attack it part by part, and get everything sorted before the final strip and reassembly with fresh paint etc.

I have/used to have some basket cases, and have learned from my mistakes.
 
cool, man.
i was going to powder coat, but decided to paint, maybe next year. if the bike runs and works good with no problems, i don't for see me selling it.
so i will get it looking half decent for next year, then go all out next off season.
i think you may have found a gem in that, looks nice and clean.
you can't go wrong with 500$, people don't realalize that most of these bikes are bullet prof and is likely have carb problems.
any way, keep me posted on your build,
thanks,
later.
 
hey jp,

makes sense, i did'nt think about the carbs drooping.
i'll have to make something up.
the rubbers are pretty stiff though, but would'nt hurt to support them.
any way, thanks.
later.
 
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