1980 gs1000e ........ TROUBLE .....

[Guest]

hi guys well i,ve just finish changing my pilot jets on my cv standard carbys from 40 to 42.5 and my mains from 108 to 117.5.. and i raised the needles to the last groove as well ,and thororoughly clean the carbys ,,,now the are back on the bike and its set at about 1300-1500 idling it idles nicelly i,ve gotNGK B8ES,,ALL NEW , it runs straight up to 7500 without coughing ,, then if i let it ease back to idle again before reving it again with a couple of revs ,,,it fluters and coughs...i,ve done this 3-4 times to know something is not right ,,, i turned it off later came back and repeated this AGAIN,,, i was going put thr ngkb7es back in and the see if there,s a differnce... the air screws set at the standard setting ,, should i adjust them , oh, i am running good oval pods and 4 into 1 system ..... when i repeatly rev it from 2500.. to 6800 or so it flutters ,,,, if i let it go back to idle it will rev straight back up to 7500 as long as i don,t keep reving it repeatedly . it start as every time nicely ... i am deserately keen on advice PLEASE !!!!

[tom203]

How to do carb boots look? More importantly, did you replace the o-rings where the carb boots meet the head?

[oldgrumpy]

How to do carb boots look? More importantly, did you replace the o-rings where the carb boots meet the head?

............ hi yes about 8 months ago ireplaced the carby "o" rings ,,, the boots origion o ring were hard and flatish ,,,,, thanks for your suggestion ,,,,, i think i may have my needle on my cv carbys toooooo high ,, which is to rich,,,, as the fluttering is mid range if i rev it 2-3 times quickly ... if i let it go back to idle and rest it will rev straight up to 7500 -8500...... i have the feeling as the mains and needle range do normally overlap maybe i should go ,,, maybe 3 up from the bottom regards oldgrumpy

[tkent02]

the air screws set at the standard setting ,, should i adjust them

There is no standard setting, just a preliminary setting. Set them by the highest idle method once you get the engine warmed up.

[hampshirehog]

Forget the revs when things are happening - it's the throttle position that we need to know. Will it, for example, rev cleanly if you just give it 1/4 throttle?

[chef1366]

Don't mess with the spark plugs.
I'd lower the needles one notch at a time until you lose most of the stumble. With the stock needle you may never lose all of it with the pods.
I recommend a Dynojet kit if you want a smooth running bike through all the fuel circuits.

[oldgrumpy]

Forget the revs when things are happening - it's the throttle position that we need to know. Will it, for example, rev cleanly if you just give it 1/4 throttle?

............. it revs at 1/4 throttle reasonably nicely ,,its when i open it up and do it 2-3 times quickly it flutters regards oldgrumpy

[TheCafeKid]

............. it revs at 1/4 throttle reasonably nicely ,,its when i open it up and do it 2-3 times quickly it flutters regards oldgrumpy

I know you've got adjustable needles on the non US carbs, and I have some of those needles and have tried them as well. They help, but still have flat spots. They're just too fat all along the taper. A Dynojet kit, Factory Pro needles, and recently I found in a stock set of BS32s from a pre 80 XS adjustable needles with some nice taper and point to them I'm keen to give a shot. When I measured them with calipers they're similar in diameter at the top but taper off to a point in the last 1/2" of the needle. Might be harder to find than a kit, but migh be cheaper and worth a shot..

[chef1366]

I know you've got adjustable needles on the non US carbs, and I have some of those needles and have tried them as well. They help, but still have flat spots. They're just too fat all along the taper. A Dynojet kit, Factory Pro needles, and recently I found in a stock set of BS32s from a pre 80 XS adjustable needles with some nice taper and point to them I'm keen to give a shot. When I measured them with calipers they're similar in diameter at the top but taper off to a point in the last 1/2" of the needle. Might be harder to find than a kit, but migh be cheaper and worth a shot..

That is some very good info!

[hampshirehog]

If she runs cleanly on 1/4 throttle that would indicate that your problem lies with either the needles or the mains. Do you know how to do plug chops?

[oldgrumpy]

If she runs cleanly on 1/4 throttle that would indicate that your problem lies with either the needles or the mains. Do you know how to do plug chops?

hi yes i do ,,,know how to chop plugs regards oldgrumpy

[oldgrumpy]

How to do carb boots look? More importantly, did you replace the o-rings where the carb boots meet the head?

hi the "O " rings and the boots are good ,,,, ,and i did replace the O rings about 8 months ago regards oldgrumpy

[oldgrumpy]

Don't mess with the spark plugs.
I'd lower the needles one notch at a time until you lose most of the stumble. With the stock needle you may never lose all of it with the pods.
I recommend a Dynojet kit if you want a smooth running bike through all the fuel circuits.

cheff,,,, i think that down the short track i will probably go with the dynojet kit ,,,,,,, which kit for my 1980 gs1000e regards oldgrumpy

[oldgrumpy]

1980 gs1000e,,,, cv carbys /????

hi guys i,m in australia,,, in a little tiny mature people town ,,, so there is NO HELP ,, on my standard cv carbys on my gs1000e,,, there is a small screw on top of the inlet alloy part of carby its only about 3-4 mm dia ,,, i was told they are vents to balnce the carbys with your gauges its the little recessed screw on top pf carby alloy inlet manifold just before the butterfly please help me here guys regards oldgrumpy

[tkent02]

No, those are the mixture screws.