eratic idle

[nisp]

hi,

i have a '81 cb 125 t and I've got a little problem with it, it had this problem before it had a set of new pistons though.

the problem is some times when i come to a stop at say traffic lights, (when the bike is warm, but not in the first few cold moments) it has a tendency to creep up its idle from about 1500 to maybe 2500 or sometimes it goes all the way up to 4K
and this problem is relay getting old and i just want it gone now

so if you got any ideas i would love to read about them, i heard somewhere it could be the condenser??
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Suzuki TS 50 1999 Honda CB 125 t2 1981 Yamaha XJ 600 s Diversion Honda cx 500 MZ ETZ 250 1985 Yamaha FZR 400 1981 Suzuki TS 185 1984 Triumph bonneville 790 2001 MZ TS250 1979 Suzuki sv 650 1999 KTM exc RFS 450 2007 Hercules mx 125 1976

[MickC]

Could be crud sticking things up in the carb/s pull em off and check the float chambers for deposits. Putting some 'magic bullet' in the tank would help to clear out any crud in the system.
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Previous: CG125,XS250 (converted to 400),Z250A, GPZ550, Norton Commando, XS500, 78 Laverda Jota, GPZ1100,Harris bonneville, XV750 (mono shock),TR1

[nisp]

not the carbs, there clean as a whistle!! quadruple checked today..
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Suzuki TS 50 1999 Honda CB 125 t2 1981 Yamaha XJ 600 s Diversion Honda cx 500 MZ ETZ 250 1985 Yamaha FZR 400 1981 Suzuki TS 185 1984 Triumph bonneville 790 2001 MZ TS250 1979 Suzuki sv 650 1999 KTM exc RFS 450 2007 Hercules mx 125 1976

[MickC]

Are all the hoses connected properly?, if air can leak in anywhere your rpm will increase. Try spraying 'easy start' around the insulators on the carbs (where the carbs go into the head) and see if your rpm increases if so check them for damage and make sure they are clamped tightly.
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XX XXXx
Previous: CG125,XS250 (converted to 400),Z250A, GPZ550, Norton Commando, XS500, 78 Laverda Jota, GPZ1100,Harris bonneville, XV750 (mono shock),TR1

[stinkwheel]

Another vote for an inlet manifold air leak. Test exactly as MickC says.

A second possability is a faulty auto-advance if it's a points model. Check it for broken/detached springs.
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[nisp]

found the problem i hope,

manifolds were lose, they were tightened to the max but there still must have been a leek so i put blue insta gasket all over the joint and shoved the whole assembly back together and didn't seem to hang around at all

problem solved must have been such a small amount tho

Job done it was really starting to get on my nerves
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Suzuki TS 50 1999 Honda CB 125 t2 1981 Yamaha XJ 600 s Diversion Honda cx 500 MZ ETZ 250 1985 Yamaha FZR 400 1981 Suzuki TS 185 1984 Triumph bonneville 790 2001 MZ TS250 1979 Suzuki sv 650 1999 KTM exc RFS 450 2007 Hercules mx 125 1976

[MickC]

We like simple solutions!
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XX XXXx
Previous: CG125,XS250 (converted to 400),Z250A, GPZ550, Norton Commando, XS500, 78 Laverda Jota, GPZ1100,Harris bonneville, XV750 (mono shock),TR1

[nisp]

yeah, i guess since the clamps were tight i thought it was something else

now i can have the full use of my brand new pistons
____________________
Suzuki TS 50 1999 Honda CB 125 t2 1981 Yamaha XJ 600 s Diversion Honda cx 500 MZ ETZ 250 1985 Yamaha FZR 400 1981 Suzuki TS 185 1984 Triumph bonneville 790 2001 MZ TS250 1979 Suzuki sv 650 1999 KTM exc RFS 450 2007 Hercules mx 125 1976