Author Topic: 1980 cb650 custom PITA!!  (Read 2651 times)

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Offline Millrunner

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1980 cb650 custom PITA!!
« on: February 20, 2014, 07:12:47 PM »
Hello everyone this is my first post. I'am new to the forum, but have used this forum for weeks to get my new 1980 cb650 running. Well she is finally alive have replaced the entire electrical system and charging system, done a valve adjustment, cam chain adjustment and timing. New plugs new cables new coils basically everything new. Took the carbs off and cleaned everything. Slows,mains, floats adjusted and mixture screws set to 2 turns out and she will fire off every time no problem don't even need the choke, my problem is she is running crazy lean due to running pods, I have new 42 slows and 120 mains coming in and went ahead and ordered some extra float valves.. 2 of them seemed to be a little sticky. It will idle and I can hop on it but I bogs at around 3500rpm so bad so I wants to die I assume this is because it's running so lean. So my question is how do I shim/ adjust the needle jets without having to split the carbs? Any help will be much appreciated.

Offline cb650

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Re: 1980 cb650 custom PITA!!
« Reply #1 on: February 20, 2014, 07:57:16 PM »
120 mains really?   90 is stock.   Dont need choke to start.  Might be a clue to.
18 grand and 18 miles dont make you a biker

Offline Millrunner

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Re: 1980 cb650 custom PITA!!
« Reply #2 on: February 20, 2014, 09:32:27 PM »
The only reason I ordered 120 mains is because all the people I have talked to and many different people on a lot of old threads on here and others said with running pods and open headers that I would need 120 mains they all said a little rich Is far better that a little lean is this false info? I will cancel the order if it is so don't want to spen 30 bucks on jets that's won't work.

Offline cb650

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Re: 1980 cb650 custom PITA!!
« Reply #3 on: February 21, 2014, 05:27:06 AM »
Pods are work.  Youll need several sets to sort them out.  Many things to consider.   120 seems excessive to me.  Thought you had them in already though.
What do your plugs look like?
« Last Edit: February 21, 2014, 05:32:19 AM by cb650 »
18 grand and 18 miles dont make you a biker

Offline Millrunner

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Re: 1980 cb650 custom PITA!!
« Reply #4 on: February 21, 2014, 03:18:44 PM »
No stock jets right now just have the others on order, my plugs are all a whitish/grey that's lean right?

Offline bjbuchanan

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Re: 1980 cb650 custom PITA!!
« Reply #5 on: February 21, 2014, 09:22:07 PM »
If you have stock stuff and pods it will be lean for sure, super lean. If you have the stock airbox, run it. If you can get one used, get one. Cheaper than all the jetting for pods, and all the work. Even if you need to buy new manifolds for it, its still cheaper with less work involved.

I'm not saying this from a purist standpoint but a realistic performance point. The airbox really works, all the mods to make pods work are just masking the issues created by pods. Drop in k&n filter, adjusted clutch, adjusted valves and let it rip.

The dirty girl-1976 cb750k, Ebay 836, Tracy bodykit
Round top carbs w/ 38 pilots, middle needle position, airscrew 7/8ths out, 122 main jet
Stock airbox w/ drop in K&N, Hooker 4-1

Don't trust me alone with a claw hammer and some pliers

Offline Millrunner

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Re: 1980 cb650 custom PITA!!
« Reply #6 on: February 22, 2014, 06:08:46 PM »
If it was possible to do what I'm doing to the bike and keep the stock air box on I would have but it's not I have a TC bros hardtail universal hard tail kit and am making a custom bike out of the cb have already done 2 other bikes 1986 honda rebel 250, and a 1982 XS had a blast and just can't stop my wife hates it though said I spend to much time on them not to keep em so this one will be mine. and I am hooked plus people say I have a nac for it who new... Thank you guys for all the input but have been working on it for a few days now put the new jets in and have found the sweet spot fixin to tear it all apart and put her in the new frame as soon as the seller comes through( got the run around bikes title has been to hard to track down and the state wants to charge me 1 1/2 blue book for a bonded title no thanks) after that gonna take the tank and fender down to be hydro dipped and a buddy of mine owns a Harley shop said we could slap it on the dyno and fine tune her from there.

Offline bjbuchanan

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Re: 1980 cb650 custom PITA!!
« Reply #7 on: February 22, 2014, 06:51:05 PM »
Try a breadbox, look up Tintop's antipod setup. You can google it using the left sided searchbar. Stacks with some type of filter in front would help

You pull the rubber boots out of the airbox and rtv them to your breadbox. Helps quiet the air turbulence and give a better signal, it makes tuning easier. I just don't like pods for all the tuning trouble. Even with a radical chop you can fit something there right?

Dyno tuning is good but on the road the side winds actually have an effect on the pods, thats why I suggest the breadbox style or something similar
The dirty girl-1976 cb750k, Ebay 836, Tracy bodykit
Round top carbs w/ 38 pilots, middle needle position, airscrew 7/8ths out, 122 main jet
Stock airbox w/ drop in K&N, Hooker 4-1

Don't trust me alone with a claw hammer and some pliers

Offline Millrunner

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Re: 1980 cb650 custom PITA!!
« Reply #8 on: February 23, 2014, 03:41:50 PM »
Thanks! I will have to look into that I was wondering about crosswinds. If it's small enough I can work with it. The problem that I had with stock air box was it's enormous amount of space it takes up. That amount of space is needed to clean up the bike and not make everything look so cramped and cluttered.

Offline Millrunner

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Re: 1980 cb650 custom PITA!!
« Reply #9 on: March 01, 2014, 05:37:08 PM »
Hey Guys new problem has developed, I no longer am firing off of number one I suspect a clogged idle circuit..... But the bike will not idle with out the choke I managed to rig it with choke on idle low enough so I could check the timing with a stobe and I am about an 1/8 to a 1/4 of an inch forward to the T timing mark the indicator is lined up with the F instead of the T is my cam timing off?