Modern Vespa

OK, I'm on day 2 of being a proud new owner of an et4 150. (Used, low miles. Odometer said 1967) I currently own 2 big bikes (Buell XB1200Rr and BMW 1100S) and a Yamaha C3 50. SO, that being said I'm not a total bike newbie BUT...

I am new to the Piaggio/Vespa world thus I'm quite puzzled by tonites behavior.

I've commuted successfully 2 days now and put probably 50 or miles on the bike. I really like the power etc.

Tonite on the way home I hit a bump (manhole divot) that wasn't that intense. No fear of busting or breaking a rim etc. Power immediately drops drastically. Behaved as it if were running low on fuel or starving for air. Will not rev to to top of the range. (happy I was close to home!)

It's posslble to keep cracking the throttle and get the revs up a little but not like normal. Is it possible I've dislodged something that would impede airflow?

Any hints?

(sorry this has to be my first post. I'm quite bummed about it. Uh... Nice to meet you folks..)

The intake manifold could have come loose. I believe it is made of a rubber compound and held by clamps.

Gratzie! I can't have a look until tomorrow. (dark and raining. Not terribly inspired to go tear into it. )

Greetings to you too!...nice to have folks in the neighborhood to reach out and help ain't it!

Yup it is. It's been my experience with both of my big bikes that generally folks with investments of this magnitude (hey, I work on the first floor and nobody calls me "sir") are eager to exchange information and lend a hand to keep one another from incurring "shop rate" shock.

Before acquiring the bikes I'd never really done much of my own work on any of my "conveyances". Now I look upon good tools almost like jewelry. (Beta...drool...)

That being said, last nights googling turned up a decent "troubleshooting" pdf for the et4. (mostly exploded views of different components.) Is there anything resembling a shop manual online? (or perhaps a pointer to a thread here with photo info for dissassembly?) I know that gaining access to said manifold could be pretty intense.

Speaking of helping hands: If anyone here owns a BMW or Buell and is not familiar with BMWST.com or Badweatherbikers.com thou shouldst get thee over there and make thine self at home. They are strong communities that have saved me well over four figure sums and provided me with lifelong friendships.

Wish me luck, hopefully tonites wrenching won't be terribly emotionally uh.."wrenching"!

http://www.wotmeworry.org.uk/manuals/ET4/



You may also want to check the spark plug wire- (this happens occassionally on the larger Vespas)

Regards
Harvey

Harvey: Your karmic score has just taken a major jump up. Thanks a pantload!

SO.....

From the photo's I've found here, and in the wiki etc... Which direction would you say is the easiest to attack from? Above or below? I've seen the shot's of "how to change a sparkplug.." which is the "loosen lower shock bolt.." etc and the "EVAP hose" pix which seem to bee directly from above. (I've not had a serious gander at the housing that is the "helmet chamber" but I'm assuming it can be removed without great trauma?)

Thanks for the help. (by the time you respond I may have the manuals down and be plotting by then.

If it's like the GTS, the helmet chamber aka pet carrier should lift right out. That's your best bet for checking if the spark plug wire's loose.


Regards
Harvey

Perhaps it's starved for fuel, not air. The ets have an issue with cracked fuel lines. I'd take a look to see if it's time to replace it. (5/32" )

good luck.

I'll have a look at the lines when I get a chance but, of course, I'm hoping it's just the intake being loose.

Once again, thanks for the the guidance.

And the winnah is........

Crap clogging up the main jet!

So, unhook all that crazy stuff from your carbs 05 people and go have a look! (Or at least run something through it that might keep the flow goin! )

Bizzare that a bump dislodged a chunk of tiny schmata that crippled my mighty steed.