Avanti GP50

Anything related to Lambrettas... ask tech questions, post helpful info, or just read and learn.
Leo
registered user
Posts: 58
Joined: Sat Apr 25, 2015 1:34 pm
Main scooter: Lambretta
Contact:

Im putting a Gori GP50 on my Avanti 225 motor. 110 x 60 crank LI150 box but can use SX200 or maybe even TV200 if I can find it.


What final drive gearing would people recommend? Don't want to plunge in a buy the wrong clutch sprocket


The GP50 pipe fits well with the larger Avanti cylinder BTW, plenty of clearance all round.
User avatar
corrado
Dealer
Posts: 2588
Joined: Thu Jan 08, 2009 1:12 am
Main scooter: Lambretta GP
Location: Top of Blackpool Tower
Contact:

Use Tony Cassidy's gearbox calculator. I'd probably aim for around 4.6 unless the Gori is a revvy pipe.
User avatar
corrado
Dealer
Posts: 2588
Joined: Thu Jan 08, 2009 1:12 am
Main scooter: Lambretta GP
Location: Top of Blackpool Tower
Contact:

Download it from here .... https://avantone.wordpress.com/
You can compare 2 gearbox set-ups side by side with it.
Leo
registered user
Posts: 58
Joined: Sat Apr 25, 2015 1:34 pm
Main scooter: Lambretta
Contact:

Cheers man.


The people I got the pipe from suggest its quite revvy.
User avatar
OAP
Dealer
Posts: 178
Joined: Wed Mar 17, 2010 10:16 am
Contact:

I would go with a 4.8:1 final drive
hendy
registered user
Posts: 859
Joined: Mon Jul 07, 2014 10:34 am
Main scooter: lambretta li 125
Location: Tyne and Wear
Contact:

Scooterdude
registered user
Posts: 796
Joined: Sat May 28, 2016 4:51 pm
Main scooter: Lambretta LI 125 S3
Location: Skaville
Contact:

It's easy to get sucked in to the whole gp50 thing with its high power output but looking at those dyno charts I'd go for the gori 50 every time over the gori gp50.
Leo
registered user
Posts: 58
Joined: Sat Apr 25, 2015 1:34 pm
Main scooter: Lambretta
Contact:

I wouldn't say I was "sucked in" The pipe I really wanted isn't readily available, Ron Moss Clubman so after much deliberating I plumped for this.

I didn't want an expansion exhaust and all the other clubman type pipes seem to have drawbacks. I asked Ron that many questions I thought I was being a pest so decided this was the one as it seems to offer what I was looking for.

I did ask on here a while ago but no one really offered any worthwhile advice and people went on about making one and when I asked what they did (being an engineer myself) no one seemed to know or have any insight so I gave up.
Scooterdude
registered user
Posts: 796
Joined: Sat May 28, 2016 4:51 pm
Main scooter: Lambretta LI 125 S3
Location: Skaville
Contact:

I was just saying the gp50, the most expensive pipe they do is the one everyone seems to be talking about but if you check out those dyno graphs it makes very good power but it has a narrow power band and peaks early.

On the other hand the gori 50 although les peak power has a much better and more rideable spread of power.

If I were getting one(and I probably will) it would be the gori 50 from Rimini, they say it has specific modifications only available from them so should be good.

I just wonder if folks are being sucked in by the beautifully sectionaly welded down pipe which to be fair looks the b@11@x.

Gearing wise: I'd say 18x47 or 4.8:1
Leo
registered user
Posts: 58
Joined: Sat Apr 25, 2015 1:34 pm
Main scooter: Lambretta
Contact:

I've got it now, I'll try it and see how it goes.

Hopefully it's not all revs and clutch or it will be coming off.
Post Reply Previous topicNext topic
  • Information
  • Who is online

    Users browsing this forum: Amazon [Bot] and 25 guests