Curvy rough idle.
 

Does the curvy SV have a rough idle as standard? Mine is not bad but I can watch the needle fluctuate by 150 rpm or so up and down.

Also, possibly related is the strange behavior when riding and stopping. Ride in first gear, brake, and into neutral, the idle rpm is around 3,000?

I stripped the carbs and found the pilot jet on the forward carb wound fully in. I backed it off 2.5 turns as stated in the Haynes manual. It seems ok now, but you never know...

It's worth mentioning the engine wasn't hot when I tested it.

All part of the rich tapestry of 90s bike ownership!

Re: Curvy rough idle.
 

Hmm. Is a choke plunger a little stuck maybe?

Re: Curvy rough idle.
 

My cbr 125 had a very erratic idle.
When I stopped at lights and held the clutch in, or put it into neutral, the idle would shoot up to about 3,500.
Whereas other times it would idle normally at ~1,500.
I took it into the garage and it turns out the choke spring/plunger mechanism was sticking.
Could be a similar issue?

Re: Curvy rough idle.
 

Yeah its a common thing on sv's aswel. Its easy to sort though. Just a screw holding it in. One for each cylinder of course.

Re: Curvy rough idle.
 

Check the balance too - erratic tickover is a common symptom.

Re: Curvy rough idle.
 

Choke plunger. OK, will check it next time. I have to anyway as the lever has about half the travel it should do, I must have trapped or kinked the cable. This was after stripping it, so not related to the first problem.

Re: Curvy rough idle.
 

Never tried carb balancing, is it something I need proper kit for, should I get a man in?

Re: Curvy rough idle.
 

If you don't have vacuum gauges, it would probably be best to take it to someone suitably equipped.