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'The problem is the lack of vacuum because of pod filters.'
That is why one of the forums I read told me to put filter foam in the pods, to slow intake speed. I didn't know about the velocity stacks in the plenum box, but now that I do, I'll try to find some new rubbers and try fitting the box again.
How could air filters possibly change your engines vacuum intake pressure, that's nonsense. the intake vacuum pressure is a direct result of that great big air pump called your internal combustion engine.

Pod filters are the cheapest, crappiest thing you could put directly onto a carburetor, that is a totally dumb idea and thousands have copied it. On a CV carb it does not work and can not be made to work as good as it should if it has all the parts it needs.
 

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How could air filters possibly change your engines vacuum intake pressure, that's nonsense. the intake vacuum pressure is a direct result of that great big air pump called your internal combustion engine.
It doesn’t change the intake vacuum. But it does affect the pressure upstream of the carb. And since CV carb slides work using the pressure differential between the intake and the air box (or lack there of), that is the issue.

Relax man! You are arguing the same point.
 

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That's half of it, the other half of the problem is atomization of the fuel which is a function of dispersion and not pressure differentials.
 

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Does anyone know where I can get the rings for the carb stacks? The part # is 13885-45450.
If that is the 4 rings that look like flat brass bird bands and fit inside the rubber stacks to make them seal against the carb better, either source NOS parts off flea bay, or your nearest local motorcycle scrap yard is likely your only hope.

(y) I fixed my hydraulic clutch today, that was easy
 

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My gs1000e had pods on it when I got

It ran like a bag of shit and used more fuel than truck

Found an airbox and filter from ebay

Re jetted the carbs all back to standard

It still looks like a bag of shit but it goes like a champion now

Its a massive bitch to get the carbs and airbox fitted especially with 40 year old rubber but well worth the effort

You have to pull back the airbox back as far as you can , slide the carbs in from the right hand side then do a lot of leavering with the biggest flat screwdriver you have in your toolbox

Fit them into the intake manifolds first then fit the airbox side

Its a bitch but worth the pain

Heat and lube help


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Discussion Starter · #28 ·
New question. My bike won't start, even with starter fluid. It just cranks. It has been sitting for a few weeks, so ethanol could be to blame, but starter fluid should bypass that. Everything is new because I just built the bike, but I don't know what is causing it to not start. Even with the pods and straight pipe, I still rode it down the road. Any suggestions?
 

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Turn the fuel tap to prime and leave it for a few minutes before you try to start it

The fuel in the bowls evaporates if it's been sitting for a while , something to do with flat slides

After its started turn the fuel tap back to on or reserve

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If you don't even get a bang off starter fluid, you are lacking either compression or spark at the right time. It's a 4 cylinder engine so generally it will at least fire on 2 or 3 cylinders, no bang at all implies you need to look for a kill switch turned off or something that is going to cause no spark.

Additionally have you done a compression test and what were the numbers on each cylinder? The engine won't run without decent compression, compression is every bit as important as fuel air and fire to make it run.

The problem with ethanol (corn alcohol) in fuel is that ethanol can contain its weight in water and still be considered ethanol, how likely is it your fuel has been exposed to water or water vapour? The chemistry to help water go through the engine is isopropyl alcohol aka gas line antifreeze, not a great solution but it is a solution. All carburetors are subject to old fuel problems because the float bowls are vented to the atmosphere unlike a fuel injection system which is a sealed and pressurized fuel system.
 

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Discussion Starter · #32 ·
No compression test yet. Spark plugs were black, probably rich. Just softened the stacks, reinserted them into the plenum box, installed the plenum box, re cleaned the carbs, installed the filter box temporarily till I get an open filter, I just left the top cover off the filter. No start. It popped off for like one or two hits, then sat there cranking. I also put some Mechanic-in-a-Bottle in the tank for the ethanol. Any suggestions?
 

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Suggest you are looking for between 128 and 171 PSI on each cylinder with a service limit of 100 PSI or she might never run. ... It's the first thing on the manufacturers trouble-shoot list:
Font Number Document Parallel
 

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If I didn't have access to a compression tester and had to just wing it; I would start by adjusting all the valve clearances to .002" (one cigarette paper folded once) and try that, because clearance is the only adjustment you can do to the valves, and during the process of adjusting the valve clearances you will be confirming the valve timing is also correct.
 

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With the airbox open like that, the stock jetting will be WAY too lean. I would start with 2 sizes over stock, and the needles at one notch under center (meaning raising the needles one notch from center). Fuel screws out 2 turns from gently seated.
 

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That shouldn't affect startup though. Isn't that the pilots job?
Yes, and no. But at stock jetting, yes. Where do you have your mixture screws set? Have you vacuum synced the throttle plates? All of these things will affect how it runs at idle. May just need to bump the idle up a bit to start getting your base line, of how it runs.
 
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