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Discussion Starter #1 (Edited)
Hey guys,

Hope I can maybe get some advice on here, I couldn't find my exact issue on the thread so I thought I'd post my stator results and bike info/issues. Mainly high RPM issues above 5k, can only get the bike up to 100kmph at 6k rpm, sorta just bogs after that and across all gears. I had the Blue wire rewired with a diode to the kill switch because it had stopped working and i read on here it was a fix and it worked to pass the certification. It was a little better when I disconnected this past week in the 5k-6k RPM but now I have to stall the bike to kill it. The ignition off switch use to kill so now I have to rewire back to the way it was. Most of this bike was this way when I got it this past winter with all kinds of electircal issues that were worked out.

Carbs were brought to mechanic who had to clean 5 times in ultrasonic and put 90/140 jets to get it running well and resynced the carbs. It was burning a ton of fuel. like 150km to 15L though the plugs weren't rich. I tried it back at 90/130 now, and built a sort of Plastic velocity stack inside the uni filter to block some of the air intake. Put new spark plugs and its still running lean at 2.5 turns out. Runs at idle around 1500rpm, will idle at 1100rpm but seems so close to dying.

New gas tank liner and cleaned out petcock. no fuel issues, or any visible leaks.

1980 CX500D - @47000kms 16" Rear wheel
Uni Pod Filters
Exhaust H box removed, 2 Straight pipe exhaust to 18" Reverse cone muffler that i repacked, still loud as hell!!

Stator - cold engine
1/5. 118
2/5. 99
3/5 212
4/5 113
6/5 98
7/5 0
8/9 81
9/5 351

3 Yellow all had continuity with each other.

Not sure which Reasan or ignitech I should get based on these results. I know the raesan hall effect would eliminate most of this system but hardest to install? or stock would be easier/ignitech?

Hope some else is having similar issues. This is my first bike so I'm no expert on how to troubleshoot this issue, I have a new clutch ready to install just for process of elimination, but then I starting looking at the stator and ended up here. Is there an easy Fix as most looks in order?
 

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Given your readings the ignitech or non hall Raesan would be easiest. The Raesan hall would be best though.

As to your carb issues? Are you sure your filter setup is not obstructing the atmospheric ports in the throat of the carb that supply the vacuum signal to lift the piston slides?
 

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There are holes in the bottom of the piston which connect to the chamber above the piston. The vacuum created by air movement causes the piston to lift. The atmospheric ports connect to the underside of the piston, keeping that side at close to atmospheric pressure. If there were vacuum on both sides of the piston it wouldn't raise properly. This could happen if the atmospheric ports are blocked. At least that is my understanding of how these carbs work.
 

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Discussion Starter #4
Given your readings the ignitech or non hall Raesan would be easiest. The Raesan hall would be best though.

As to your carb issues? Are you sure your filter setup is not obstructing the atmospheric ports in the throat of the carb that supply the vacuum signal to lift the piston slides?
I have cut the rubber back to the OD diameter of the Air intake on the carb to ensure it isnt blocking anything, really havent noticed any difference from changes to air filters, though would be open to suggestions. i feel 140 is too big
 

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2019 and you're still trying to diagnose CV carbs with pods?

Bro. It doesn't work. If it did, honda would have done it.

You need an airbox.
i build the mikuni kits so i am not one to push fiddling with the kehins and have no magic pill to offer for them

that said there are 10s of thousands of happy riders running pods with decent if not perfect performance on there bikes

so it is really not helpful just to say it cant be done as it is everyday all over the world its just the level of perfection you desire

and to the poster put a rae san in make sure your float levels are correct do the brass rod mod and check your coils

then start with 90/120

take the stack out of the uni and make sure it is only very lightly oiled
t
 

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There you go garrettb...problem solved. Now all you need is GL650's location.
 
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You would lose that bet to more than me Larry could take your money on that one as could few other people

The proof being driveability and dyno

And that is not to insult you but there are a few of us that have spent 30 plus years working with a lot of different racers developers and riders

Using fancy equipment most dont ha access to plus countless
Dyno hours (just ask my wife who says I cant hear)
Playing experimenting ect

Now in the spirit of full disclosure I have a modded gl650 cafe with rae San ignition a few other trucks and 36mm flatslides

And I have a bone stock except for jets gl650 that I also just love I get around 45 mpg on it and ride it a lot my wife has gotten 50 mpg on it
My cafe on the other vcd hand about the best I do is 33mpg

But a much wider grin

So to each there own but not to many absolutes we have all been proven wrong that is what makes me look to tomorrow


Maybe I will find a 2 into 1 that makes more power than true duals
 

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A thought I'd had was to make a short stack, as wide and long as the space permitted but keeping the total diameter of the end of the stack to less than 100 mm.

Then setting a 'rest ring' about 35 mm down the tube to take a wire screen. On top of this oiled filter foam can be added a layer at a time until the bike has the appropriate vacuum to run properly with some more normal jetting like 82/118.

Might try it one day.

Along with lightened and balanced slides and some wet and dry towards the end of the needle to prevent WOT lean out without going for huge secondary jets.
 

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Good idea, unfortunately you arent producing vacuum you are just slowly restricting air... also if you.are running stock jetting in pretty much any CV carb from that era then you're not getting all the power or driveability that you could.

I'm tellin' ya fellas. CV carbs need a controlled, static volume of air and a specifically sized intake to function optimally. That's just how they are engineered.
Stock jetting is 78/112, - 78/115 on the 500C.

Also, aside from being a still airbox any intake snorkel is an engineered balanced air restriction. While not the same at least 'end on' air entry is less disturbed than a pod drawing through the sides. The shape of the funnel is important here for air direction but must be balanced to an acceptable filter area.
 

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Discussion Starter #12
Thanks for the info murray, I ordered the rae san, I'll start there and work through what you mentioned.

Seems I've started a bit of a debate. I got the bike the way it is with no airbox.
 

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dont worry about the debate do the bike how you like and so you enjoy it

the:debate has been going on forever and at the end of it this is he facts

cv carbs stand for constant velocity

so that includes the overall designed environment that tons of engineers spend lots of time per model

fighting for the best balance between packaging (it all has to fit on the bike) power and economy and emmisions

so whenever you tamper with the environment one or more of those items goes whacky

but you can actually have a good running bike and in some cases improve one of the items in the list commonly either power or economy

some say the pods improve packaging

however you will never get them all better and in as perfect harmony

but as i said there are thousands of people out riding there bikes today het good pods not cheap ones

do a bit of tweaking and go join them
 
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