Unstable and Hanging RPM's

[Pat Conlon]

Happy to help

[Warp84]

Update, finally had a good day for more testing and putting more miles on the bike.

60F outside temp, low wind's. Brand new Metzeler Lazertek Tires. Stock 1100 pistons. Stock exhaust. Replaced exhaust header gaskets to correct exhaust leak. Replaced intake boots recently. Resynced Carb's on digital man-O-meter. Pilot Fuel Jet's are 42.5's. I'm not sure if the mains are 110's or 115's right now.

Idle adjust screws are currently at 2.25 turns out.

Bike doesn't hesitate at 4k rpm, but still has the rapid ticking up and down by a thousand rpm, every second, whenever the RPM is between 3.7 to 4.5k rpm. Above or below those RPM's and the needle on the cluster is behaving.

Bike is also wanting to rocketship as soon as it touches 4k rpm, taking only a moment to hit 6-7k, when in first gear. I've been told that is normal. For the bike to "Wake up" and want to go.

I'll keep fiddling with it to get it more dialed in.

[86FJNJ]

The rapid ticking up and down on the rpm:

Option 1: Is it just the RPM gauge needle that is bouncing around but the engine RPMs are consistent?

Or

Option 2: Are the engine RPM's going up and down and the RPM gauge is just accurately reflecting that?

My RPM gauge need does the same, seems to get drunk between 3k-6k rpm and bound around but the engine RPM's are fine so I chalk it up to the bike being 40 years old

[Warp84]

It seems like the RPM's are stable even while the needle is ticking, going by the sound. Good to know that it's not just my bike that has a RPM needle that likes to dance.

[86FJNJ]

I'll stay tuned if anyone has a cure but my bike rides fine