Modern Vespa

I made a appointment with a Vespa dealer in Maryland (82 miles each way) for service on my sons scooter.We picked it up and as I was looking at the bill it did not show a valve adjustment.The service manager told me they check the compression and if it is ok they leave the valve alone.( 621) miles.Have you ever heard of this? thanks

The users manual says that valves are to be adjusted at 1000km (600 miles). They should have told you that they weren't going to perform that service when you made the appointment.

If it were mine, I wouldn't worry too much about it as long as the scooter is running well. I would have the next service done maybe a little early and have the valves checked then. Or, since I mostly do my own service, I'd check the valves myself at the first opportunity.

My owners manual shows to check valve clearance at 620 miles that's why I took it in.The next time I will do it myself.

I called another dealership closer to me and they told me the same thing that they check compression and if that is good they leave the valves alone and have been doing this for sometime.What do you think?

I think that since the book says to adjust the valves, that should be done.

I've had a couple of scooters that benefited from a valve adjustment (though they weren't new) so I think it's important.

I think that it is important to follow the owners manual.

I ain;t not expert but a compression test would probably allow a simple check of if a valve is loose but not if it's too tight.

fyi this is one of the reasons I do my servicing myself as my mechanic was of the mindset of only touch them if the engine sounds wrong

I think you are right about adjusting instead of a compression test. Thanks

I went about 20k miles and didn't have to adjust my valves. Finally, at 20k I took apart my engine to change the gasket and the valves were still in a good shape. I guess it depends how you ride ur scooter.

It is part of the 600 mile (1000 km) service. I would call the dealer and tell them that not doing the valve adjustment could void the warranty. My dealer didn't have the valve adjustment on their list, so I showed them the table in the manual. They updated their software to include it.

Besides that, it is very important. Valve adjustment on air cooled engines is critical. Ask anyone who has ever owned an air-cooled VW that lasts over 100K miles (a check every 3000-4000 miles is what I did, along with an oil change every 2000).

As time (miles) goes on there tends to be less and less adjustment and sometimes none at all. But, at least the 1st two or three adjustments are important for engine life.

If the valves get tight (usually the exhaust) they can burn quickly. It is worth the money (or time if you do it yourself). Cheaper than a head job (no not that kind), or worse yet the valve drops and you are looking at a whole new top end.

If you decide to skip it, then one of the warning signs of tight valves is that the engine will stall at idle when hot (like after a long high speed run), be hard to start, and sometimes backfire. At that point it is nuclear critical to adjust.

At 600 miles the service at my Vespa dealer was about $200 and did not include valve adjustment. I asked about this. They said the big additional cost made customers mad and was rarely needed. For warranty reasons, I just documented that. Bike has always run perfectly!

That's what they told me also

It's not a big job though assuming the bike is already on the stand for oil etc. 30 minutes?

you have to disconnect a few things like the suspension so the rear can be lowered pivoting the head upwards. even then it's a real pain to reach the exhaust valves when sliding the feeler gauges in. the intake valves are pretty easy once the engine is tilted


Edit: I used the meaning of "tight" the opposite way around to convention here. so when reading this please swap the words around

This may just be clarification, but tight valves would be the ones to fail a compression test. At least as I understand it, "tight" refers to a lack of clearance between the valve and the actuator that presses down on the valve to open it.

I was using "tight" the other way around. ie tight equals the valve closing hard. but actually I think your usage makes more sense so please swap the words I used in my comment around

Tight valves spend less time on the seat which is where they dissipate heat.