Clicking noise in carbs in problems over 4k

[ty998]

I thought I had my bike running well finally (since buying it with problems), but after my first real test ride I am experiencing two problems:

1. There is a clicking sound coming from one of the carbs on left side. It is inconsistent and I hear it about every 20-40 seconds. Also when the click occurs I see a little flash in the vacuum line.

2. Any acceleration over 4k sounds really bad. Up to 3500 it sounds good. Then at 4k it there is a lot of clatter. Note: I have not synched the carbs since cleaning them. By "cleaning them" I mean that I cleaned the jets and did everything except disassemblying each one individually and dipping them. The bowls were very clean. Note: I have also not validated valve clearance yet.

Previous owner also mentioned that a technician said one of the slide needles would need to be replaced.

Anyway, any advice on above problems would be appreciated!

[OldVet66]

There are no short cuts, I would park it until you do all the required maintenance before you really do some permanent damage. A spit from the carb could be a lean condition. Your other sounds could be detonation or pre ignition. None of it is good. Start with the valves, rebuild the carbs by the book, total tear down, soaking, replacing O-rings, bench synch and vacuum sync. Then the electrical system, brakes, brake lines, etc. There is 30 years of neglect that needs addressing before you have a safe reliable ride.

[koolaid_kid]

Those two things are crucial in attempting to revive these bikes. You must check the valve clearance and you must completely rebuild the carbs. Shortcuts will not work.

[Big T]

What bike are you talking about?

A Puch moped?

[Andersonspartsplus]

Hi,
these GS motors will take a lot of abuse however you will be better off sorting it out. Some of the noise could be from the timing chain. Look for the threads explaining proper adjustment. Valve adjustment is a MUST as everyone else has said.

Although it seems scary just take your time with the carbs and do it correctly.

A lot of the old bikes we find have been neglected for many many years. You will not be doing yourself any favors by not going over every thing and making sure it is correct.

There is a valve shim pool on this forum. If you take your valve cover off and follow the procedure for measuring valve clearance you can buy from the pool and save some money.

Also remember saftey issues.

Hows the chain? Do any of the links ball up and not flatten out? How old are the tires?

[bbjumper]

Trying to diagnose a poor running condition on one of thees before doing ALL of the required maintenance is like a blind man swattin at flies, only funnier.

Do yourself a favor and save allot of frustration.

[chef1366]

Clicking is probably the vacuum petcock.