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Discussion Starter #1
I recently purchased a 71 CB175, and when I first bought it, it ran but not the best. I rebuilt the carbs, changed the oil, bought a new gas petcock, a new condenser, new plugs, cleaned the points,cleaned the gas tank, and bought pods. The bike was running after the rebuild, but was bogging under high acceleration. While adjusting the carbs, the bike would not get any better, and then one day it wouldn't start altogether. I am getting spark at both plugs (replaced the condenser after checking this because points were arcing) and am getting fuel (the float needle isn't closing on one side so it leaks, so I know there is gas in the carb). At this point, I'm ready to sell the bike. Can anyone give me any last minute tips or things to check out before I give up once and for all?
 

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Compression OK?

Were it mine I would try it with the stock airbox and filter in it. Pods can really mess with some bikes, causing symptoms similar to what you described.

How are you timing the ignition?

Will it start momentarily with a quick spritz of starter fluid? (Don't catch it on fire!)
 

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It ran with no filters before, don't have stock air box. The pods were merely to prevent the gaping hole at the back of the carbs that were previously there.
I don't have a compression tester, but there is a good amount of compression using my finger to plug the holes.
 

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Not sure about the timing, do you mean points adjustment? And the starting fluid is a no. It won't make a difference.
 

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Ya, the points adjustment. You set the gap, but you also have to set the timing - where in the stroke the points open. I guess my point is you may have fuel and spark but, if things don't happen at about the right time it won't run. Did you accidentally connect each point to the wrong wire?
 

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Discussion Starter #6
There is only one point on it as far as I'm aware, and how would you adjust the timing when the points open?
 

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I've worked on a lot of old Hondas, but have no direct experience with your particular bike. That said though, I'm fairly sure it's the same procedure as the others. The plate that the points are mounted on should turn a bit.

Here's a useful link:

http://www.dansmc.com/bat_coil_ign.htm

You have to set the point gap, but you also have to static time it, otherwise it probably won't start or run well.
 

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Discussion Starter #8
New development, timing is much better, but found out that when the plugs are grounded to the block, there is no spark. What would cause this?
 

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Ignition and kill switch on, are you getting 12 volts to the points?
 

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'The float needle does not close on one side so it leaks"

BAM There's your problem. The whole idea of the float needle is to shut off the gas at the proper level for the carb to work correctly. It can and will throw off the fuel mixture.

Another thing that could affect things is a sinking float or float height not correctly set.

To test the sinking float, I immerse the float in a container of warm water about what you would was dishes in and if it bubbles, the solder is cracked and a new float is needed
 
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