Vespa ET4 Malossi 190cc Problems
Post Reply    Forum -> Project Reports
Author Message
Vespa et4 125
Joined: 02 Jun 2018
Posts: 1
Location: London
Sat Jun 02, 2018 1:24 pm quote
Hello people, Iíve got myself into a giant pickle and need your help to get my out of it. Lol

Ive had my Vepsa ET4 125 Leader for nearly a year now. Its maxed out at 65mph, I wanted more speed. So went and bought a Malossi 190cc cylinder kit.

When installed the I rushed staight in thinking i knew what I was doing and didnít leave any marks on the timing chaing or take any pictures. When putting the piston rings on (while the head was off) I was spinning the crank with not a care in the world not knowing that i was the timing up. I out it back together and It didnít start.

So i did some research on how to set the timing and managed to get all the timing mark correct.
When I started her up... the engine Was worryingly loud and when I reved it started backfiring.

What should I do
Vespa Sprint 150cc
Joined: 13 Jul 2017
Posts: 18
Location: New Orleans, LA
Sun Jun 03, 2018 2:33 pm quote
I did the same on my ET4, the engine was louder but mine didn't backfire. Besides the loud nice does it run? Have you looked at your carb settings?
73 Rally, 74 Rally, 76 ET3, 80 P200, 63 Li125, 65 Li225 Silver Special, 86 Elite 80, 2015 HD Road Glide Special, 2011 Ural Tourist
Joined: 18 Jan 2012
Posts: 3278
Location: Oceanside/ SF
Sun Jun 03, 2018 6:33 pm quote
I'd pull the motor out of the frame and take it to a garage. Take any non essential plastic fan covers off and have them sort it out. That way they can find TDC and line up the timing chain correctly. Then you can install it. Much better than it running rough or ruining the new kit.
09 190s taormina
Joined: 08 Apr 2010
Posts: 2082
Location: Googleville
Mon Jun 04, 2018 2:04 pm quote
1) are you sure it's not just an exhaust leak?
2) possibly still off 1 tooth, did you double check timing?
3) bent valve?
ET4 187
Joined: 14 Mar 2017
Posts: 324
Location: Germany
Tue Jul 03, 2018 6:59 am quote
Duane, did you get things sorted out?

The backfiring, did this happen when you let off the gas?

The loudness and backfiring, seems to me too that the exhaust may be the culprit. A rag placed against the muffler pipe with an idling motor will soon tell the truth. A leaky exhaust system will allow the motor to still run, otherwise it will stall.

The carb is probably not important yet, it'll still run nicely with the original carb and settings just as they were before kitting. Later on though, the motor really wakes up with a richer adjustment.

It's a good idea too to replace the intake gasket as well.

I hope things work out for you.
Team Scooter Trash for Petfinder Foundation   vespa scooterwest scooter west Motorsport Scooters   Scooter Parts Company
Post Reply    Forum -> Project Reports
[ Time: 0.1299s ][ Queries: 23 (0.0341s) ][ Debug on ]