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I have compression tester.i don't have leak down. I can get it to fart and pop when trying to start. I cleared and cleaned the float bowls and adjusted all floats to 26mm spec. I know I'm hoping for 90%compression and 10% difference. The leak down will be the hardest part. I have not pulled the carbs off the rack and checked the needles. That's actually what I'm a bit afraid of because syncing them seems like a bitch. I want to get it running and then I will start working on chain, brakes, wiring etc. So next I'll do compression test...then what do you recommend? Leak down or check needles?
Reread my last post. You don't absolutely need to buy a leak-down set up if you don't think you'll need it enough. As far as balancing the carbs there's a device called a "Unisync (sic ?) if they still are made and you can find one. I've tuned literally hundreds of race cars with one of those. What it does is you place it over the intake opening of the carb. and it measures the air passing by on a scale. So all you do is adjust the carbs so the little ball in the measuring tube is the same for all four carbs. If I remember Summit Racing used to have them. If they're still made they're not that costly. This said at one time I have taken a chunk of hose and just listened to the sucking noise that the carb makes and made them all equal. It's not perfect but will get you by if you have a good ear for this kind of thing. At the very least you cam get it running fairly well this way.
(y) 2 X on having a workshop manual for every bike you own. I do exactly that unless I'm just passing it on and even then Ioften hate not having one and always running back into the office to look something up. If you are keeping it do as TR says and get a shop manual. :unsure:
 

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Reread my last post. You don't absolutely need to buy a leak-down set up if you don't think you'll need it enough. As far as balancing the carbs there's a device called a "Unisync (sic ?) if they still are made and you can find one. I've tuned literally hundreds of race cars with one of those. What it does is you place it over the intake opening of the carb. and it measures the air passing by on a scale. So all you do is adjust the carbs so the little ball in the measuring tube is the same for all four carbs. If I remember Summit Racing used to have them. If they're still made they're not that costly. This said at one time I have taken a chunk of hose and just listened to the sucking noise that the carb makes and made them all equal. It's not perfect but will get you by if you have a good ear for this kind of thing. At the very least you cam get it running fairly well this way.
(y) 2 X on having a workshop manual for every bike you own. I do exactly that unless I'm just passing it on and even then Ioften hate not having one and always running back into the office to look something up. If you are keeping it do as TR says and get a shop manual. :unsure:
BB,
One other thing I saw on your post and think should be mentioned> When you are speaking of needles I hope you are refering to the float needles. Those are the little ones that often have rubber inserts close to the pips. The needles in the slides have nothing to really do with if the motorbike will start and idle. Worry about the small ones unless the slides are stuck and then the problem is the slides or a bent needle. Just thought I should say something. Now I'll shut up !
 

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Clean your carbs again.

If it won't start and everything else is good, fresh petrol, air (does it have the original air box or shitty pods?) any compression and spark it'll most likely be the pilot jets and the other tiny ports and passages that old fuel clogs, it'll cough when you drag a bit through a main jet. Best way to clean them is in an ultrasonic cleaner but even that might not work. I had a pilot jet on an RF that wouldn't clear until I left it soaking in carb cleaner for days, stood well back and put a 100 PSI through. Is the timing set right? When did it last run? Has anyone tried re-jetting it as that's a big problem with ham fisted, cafe wankers.
 

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Discussion Starter #44
Reread my last post. You don't absolutely need to buy a leak-down set up if you don't think you'll need it enough. As far as balancing the carbs there's a device called a "Unisync (sic ?) if they still are made and you can find one. I've tuned literally hundreds of race cars with one of those. What it does is you place it over the intake opening of the carb. and it measures the air passing by on a scale. So all you do is adjust the carbs so the little ball in the measuring tube is the same for all four carbs. If I remember Summit Racing used to have them. If they're still made they're not that costly. This said at one time I have taken a chunk of hose and just listened to the sucking noise that the carb makes and made them all equal. It's not perfect but will get you by if you have a good ear for this kind of thing. At the very least you cam get it running fairly well this way.
(y) 2 X on having a workshop manual for every bike you own. I do exactly that unless I'm just passing it on and even then Ioften hate not having one and always running back into the office to look something up. If you are keeping it do as TR says and get a shop manual. :unsure:
Planning on getting the factory manual then! I saw what you said on rigging the leak down but to be honest I would rather buy the proper tool for the job. Your unisync sounds far easier than what I've seen elsewhere for syncing the carbs. I'll update you with results of compression testing and leak down when I get around to it!!
 

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Planning on getting the factory manual then! I saw what you said on rigging the leak down but to be honest I would rather buy the proper tool for the job. Your unisync sounds far easier than what I've seen elsewhere for syncing the carbs. I'll update you with results of compression testing and leak down when I get around to it!!
Good show I to am a big fan of having the right tools AND the last forever can't say that about a lot of things. Look forward to hearing what you find was your problems. Being a detective is half the fun.
 

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Good show I to am a big fan of having the right tools AND the last forever can't say that about a lot of things. Look forward to hearing what you find was your problems. Being a detective is half the fun.
As Andyshep said getting the jets clean is major importance replacing them is not very costly and a surer way. Harbor freight has an reasonably good ultrasonic cleaner that's not too costly and it works rather well. I use high-test Simple Green in mine and that's also good for soaking bits. If you need to rebuild brakes and/or suspension the ultrasonic will help a lot.
 

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Discussion Starter #47
As Andyshep said getting the jets clean is major importance replacing them is not very costly and a surer way. Harbor freight has an reasonably good ultrasonic cleaner that's not too costly and it works rather well. I use high-test Simple Green in mine and that's also good for soaking bits. If you need to rebuild brakes and/or suspension the ultrasonic will help a lot.
Already have an ultra sonic cleaner! Will keep you updated!
 

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You know what you really need right now! You need somebody to show you how to disassemble, clean and re-assemble a motorcycle carburetor that has been doing it for way too long. Good news is, almost all of your problems will be in the bottom half of the carburetor because that is where the fuel is, everything above that is suppose to be clean filtered air.

I have them but never once needed an ultra-sonic cleaner to clean something I can take completely apart to service.
Anything that was built can be accessed the same way to be cleaned. I've also seen things destroyed by improper use of an ultra-sonic cleaner
ymmv.
 

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You know what you really need right now! You need somebody to show you how to disassemble, clean and re-assemble a motorcycle carburetor that has been doing it for way too long. Good news is, almost all of your problems will be in the bottom half of the carburetor because that is where the fuel is, everything above that is suppose to be clean filtered air.

I have them but never once needed an ultra-sonic cleaner to clean something I can take completely apart to service.
Anything that was built can be accessed the same way to be cleaned. I've also seen things destroyed by improper use of an ultra-sonic cleaner
ymmv.
Hey TR, I usually agree with what you say but (LOL :pthere's always a but or a butt) as to the sonic cleaners we will have to agree to disagree. Maybe because I work on both vintage motorbikes and sometimes late 1800's fire arms keeping things looking either as they came from the factory or only showing wear I have always tried to preserve the finish or what is left of it. Because of this brushes and scotch brite pretty much are out except for soft nylon.

Most of the carburetor cleaners are either too caustic or don't work for crap. When working on the vintage and race bike bits that are in need of a scrub I have found that the sonic cleaner is the least invasive. With carbs, calipers and master cylinders I soak the bits in super high test Simple Green for an hour or two. I then fill my cleaner with almost boiling 50/50 Simple Green solution . I usually run the parts thru about 3 cycles in the cleaner, blow dry them flush them with a quick rinse in acetone then hot water and let dry. The parts usually come out looking like NOS bits right out of the box.

I will admit that I get a wee bit paranoid on how thing clean up as I once had a customer get major negative mark downs because the float bowls on his motorbike were clean as can be but on the bike as it left the dealer those suckers were very (and I mean very) lightly polished. So I want my stuff to look new or used with much love.

Cheers
 

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The original equipment service manuals all have it under "trouble-shooting"
is the Honda service manual available free online anywhere? Seriously, I could probably read it in a couple hours :|
OEM Service manuals are awesome, you should buy one immediately for every motorcycle you ever buy.

... 4 carburetors; you are going to need to balance the carbs as well as getting it running on all cylinders.
(y)
 

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I clean a carburetor just like I would clean a gun,
or a microtome. Norton honing stone oil mostly
and with a stereo microscope.
 

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I clean a carburetor just like I would clean a gun,
or a microtome. Norton honing stone oil mostly
and with a stereo microscope.
See we do agree most of the time. I will say with the old guns both rifles and pistols if the owners have not been using black powder substitute but real black powder then almost the only thing that gets them clean is soap and hot water. With the lever guns the gunk gets everywhere inside. Sometimes it even slows the magazine tube and you get feeding jams. Most shooter don't take their fire arms totally apart to clean them so when I get them they need a good soak. On the other hand I bet you could dig a 1911 Colt outa a hole in the ground beat it on a fence post and it would work just fine.
The old guns are kind of like brake systems, float bows, petcocks and OMG what I've found in some air boxes. Then the oil and carb clean comes out.
We had just finished getting a KTM that had been sitting for quite a while back running. The fuel had turned to what looked for all the world like Jello. The stuff was bloody well everywhere. We cleaned the whole system even the tank. When we filled the tank up and looked down the filler neck that crap was back; floating on the top of the fuel again. Finally put a handful of ball bearings in the tank with some special fuel tank cleaner and sloshed the cleaner around for like 20 minutes. When we poured the crap out it looked like swamp water. After we rinsed the tank looked pretty good. Have you ever seen that sort of Jello mung ?
 

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Worst thing I ever had to clean and service were cryostat microtomes, you know what those are?
When the doctor has you on the table cut open and wants to do a quick microscope biopsy, they freeze process and thin section cut your bits with a cryostat microtome. 😷 I used to call the stuff in the bottom of the freezer cabinet and all mushed into the microtome soylent green.
 

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LOL didn't really know what it was until I thought about it. Sounds like a mini deli meat slicer to me.
My wife and I were volunteer ambulance crew for the car and motorcycle races so my worst is the gunk that drains down between the floor and the sliding gear on the side door of the ambulances. Wasn't too bad if you got to it right away but if it was a hot day and you had a couple of back to back runs ................then I tried to get her to do it......never worked !
 

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Yep, that's the stuff, soylent green is made from people.
Meat and bone slicer that has to slice one cell thin without making waves and ripples.

I had to service the microtome at room temperature and then when they stuck it into a cabinet at 80 below zero it had to shrink to the correct clearances to work nice. I got real good at it 😷
 

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Discussion Starter #56
Update, compression all tests between 123psi and 126psi on all cylinders. Pod filters cleaned, Carbs cleaned in ultra sonic cleaner and are in, new float needles, adjusted floats. Now runs but does. Idles kinda. Air screws are all at 1.5 out. Not sure what to set the screw that controls the throttle at the top. I have a manometer to get them all spot on once I can get it to stay running. What next?
 

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Fit a proper air box and ditch the pods. Forget about trying to keep the open triangle look.
Thank me later when the bike actually idles and pulls through the rev range
 

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Discussion Starter #60
Sweet. That should give a decent base line to work from.
Once I get the stock air box what is the process with establishing and finding the carb baseline? I did t really see that process in the service manuals I have
 
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