Topic: Confirming Indicators of a Problem

[Freebirdbeachbum]

Recent purchase. The PO said its had little use since he bought it 20 years ago. He planned to restore it but aged out. Lower mileage on the OD. I didn’t run/ride it but once up and down the street. Would have ridden it more but some non-engine or gearbox related quirks made me feel unsafe.

Starts right up. Doesn’t smoke. Plugs look like it may be running a bit rich. However, compression #s are 85-77.5-77.5-72.5 (on an ice-cold motor), which is not awesome.

Before you ask about a leak-down test...no, I haven’t but based on what I know currently, what should I think of the low compression?

[PeWe]

Which bike?
Did you fully open the throttles during comp test? If not low values.
Low values can also be caused by no valve lash, not closing valves if adjusted wrong.

[Don R]

 Many of these test low especially with a big automotive gauge. One that has sat a long time can test low too, I'd fix only what it takes to make it safe first and put some miles on it. Then if it passes the fun test continue to improve on it.
  Don't be quick to assume it has problems.

[BenelliSEI]

+1 to what Don says. Put fresh gas in it and run it for a while..... we often tear into things that really just need a tune up! Warm it up a few times, adjust valve clearances, clean points and set timing and then synchronize the carbs. You may be surprised how well it will run!

[Don R]

 You got me remembering my first ride in 30 years on a 750,  It had a scary wobble at some speeds, probably a combination of a loose swing arm, original shocks on lowering blocks and flattened neck bearings. 70 mph seemed unsustainably fast. I did a hundred mile trip, without proper registration and once while I was stopped rocking the handlebars back and forth to mix up the flat spots on the neck bearings I realized I was being observed by three Illinois State Police motorcycle cops.  I'm sure they were laughing, or at least wondering what the hell?  I turned at the next three corners and beat it back home.

[evinrude7]

+2 on what Don said.  get it moving.  change the oil regularly.  do the tune up stuff.  it'll probably surprise you.