Compression spec for Quota

[Rafael]

Anyone know what the compression for the Quota is suppose to be? I tested the engine after the valves tappets were adjusted and a warm up. It tested at 110 psi on the left and 100 on the right. One of the spark plugs looks oil fouled but its not wet.

thanks for any help, Rafael

[john zibell]

That engine is the same as all the other EV type 1100s. A tight engine usually produces 150 PSI or more with the throttle wide open. Try your gauge on another Guzzi engine and see what you get. The gauge may be off, or read differently than mine. You did have the throttle wide open when you tested? The 10 PSI difference is marginally acceptable, but your pressure readings are low.

[Rafael]

thanks John,
I realized after my buddy left with the Quota that we omitted having the throttle wide open. Oops. We were too focused on jumping the starter and taking the reading that we forgot to deal with the throttle. We'll try again later this week. The only other 1100 guzzi we have handy for testing is a Breva, no match. Our gauge isn't the best; not sure if it can be tested.

This motor has some other symptoms as well, we're slowly getting sorted and hoping they'll clear up and that a rebuild is not needed yet.

[Rafael]

Well, its been almost a year. Have the TB balance, TPS adjusted and a PC3. I retested the compression with the throttle full open but the engine was cold, got 132 and 135 pounds compression -still a bit low. Is there a way to figure out if its the rings or the valves without taking the heads off? It would be nice if all it needed were some new rings. This may be anew winter project.

[john zibell]

Well, its been almost a year. Have the TB balance, TPS adjusted and a PC3. I retested the compression with the throttle full open but the engine was cold, got 132 and 135 pounds compression -still a bit low. Is there a way to figure out if its the rings or the valves without taking the heads off? It would be nice if all it needed were some new rings. This may be anew winter project.

Perform a leak down test. If you don't have, or don't want to by the equipment have a shop do it. If you hear air at the intake or exhaust it is valves, if at the crankcase, rings. That said, in my experience, if you do valves without doing rings, the extra compression will soon take out the rings. So, in my experience, if it fails the leak down test, just do a complete top end job. It will save going back in a relatively short time to take care of the problem you didn't fix the first time.

[pete roper]

Before you do the leak down test make sure that the valves all have clearance otherwise you'll get a false reading. As John sez, if one or other part is leaky just bite the bullet and do the whole thing otherwise you'll just end up pushingthe problem from hither to yon and back again. At least if you give it a complete freshen-up it should be good for another 20 years!!!!

Pete

[rboe]

After a dyno run giving me only 50hp at the rear wheel I tested the compression. 150psi. Not knowing if this was good or bad or what (my old KZ550 had 190-195psi, the only other bike I knew about) so I went to Greg Benders place and we did a side by side with his bike as well as the leak down test (he had the tool for that).

My bike was fine, he had a leaky exhaust valve; so my concern lead to discovering a problem on his (now ex) bike.

After recently dumping the Super Trapp muffler and going with the stock unit I am suspecting it was the choke point; need to do another dyno run to confirm.

Ron

[pete roper]

You had the throttle wide open when you performed the test?

[Rafael]

I tested the compression. 150psi.

See Johns comment above.

usually produces 150 PSI or more

[rboe]

Update; had the bike dyno'd and I gained about 12HP by going back to the stock can. 63peak hp and better torque. I'm stoked!

Now that I'm getting used to the big guy another twenty horses would be nice. That new V12 that we've been teased with has really got my attention. If they don't drag their feet bringing it to the US I'm seriously thinking of pulling the trigger on it.