Alternative crankshafts for a TV175

Anything related to Lambrettas... ask tech questions, post helpful info, or just read and learn.
fluff34567
registered user
Posts: 388
Joined: Tue Dec 20, 2016 2:27 pm
Location: Switzerland
Contact:

Hi all,

I have been trying to find a GP style crank (thicker taper) but with a 116mm con rod. . So far I haven't found one for sensible money.

From what I know the standard is a 58mm stroke often refered to as 58/116.

I have been offered a 60/116.

Am I right in thinking all i need to do to use the 60/116 is install a 2mm case to cylinder packer/gasket?

If I change to a 60/116 what else do I need to consider.. any fueling or piston/porting issues?

Thanks for any tips.
holty
registered user
Posts: 908
Joined: Wed Jul 15, 2015 11:52 pm
Main scooter: lambretta gp
Location: east yorkshire
Contact:

with a 60mm stroke your piston will go up 1mm farther and 1mm down, more than a 58 stroke, so if you raise your barrel 2mm you might find your piston goes below the exhaust port by 1mm if its standard ports, some porting work can correct this, but it depends what kind of tune you want, eg a tourer or street racer ?
fluff34567
registered user
Posts: 388
Joined: Tue Dec 20, 2016 2:27 pm
Location: Switzerland
Contact:

Tbh it will only be used as a local run around with a possible small day tour and nothing more.
Adam_Winstone
registered user
Posts: 1693
Joined: Tue Jan 31, 2012 8:54 pm
Main scooter: Lambretta GP
Contact:

You should be able to get a GP crank with standard TV 116mm rod at a decent price for a very reasonable price.
fluff34567
registered user
Posts: 388
Joined: Tue Dec 20, 2016 2:27 pm
Location: Switzerland
Contact:

I have looked about but only finding some for £300 + I spoke with Glasgow lambretta and they have the 60/116 for £125, no stock of the 58/116.

I had a message with 1 contact so will try that in the morning but any known stock suggestions would be greatly appreciated.
Adam_Winstone
registered user
Posts: 1693
Joined: Tue Jan 31, 2012 8:54 pm
Main scooter: Lambretta GP
Contact:

AF Rayspeed should be able to put you a TV rod into some new SIL webs for considerably less than £200. Indeed, many dealers should be able to sort you one out for a decent price.

Make sure that you also address the difference in mag side bearings if changing to a GP200 based crank.

In your shoes I would phone AF Rayspeed (you will need to try many man times as they are busy and often don't pick up), Harry Barlow, Taylor Tuning, Scooterotica (I'm not joking), and ask them for a price. There are lots of outlets for such a crank but don't expect to find one on a website.

Honestly, this should be very easy to source at a decent price.... and I mean a decent product at a decent price.

Good luck.

Adam
fluff34567
registered user
Posts: 388
Joined: Tue Dec 20, 2016 2:27 pm
Location: Switzerland
Contact:

Cheers Adam will give a call to all those mentioned. Really appreciate the tips.
fluff34567
registered user
Posts: 388
Joined: Tue Dec 20, 2016 2:27 pm
Location: Switzerland
Contact:

Ok it's in the US. I'm there every few weeks but for now i will try for something in UK /europe.
Post Reply Previous topicNext topic
  • Information
  • Who is online

    Users browsing this forum: Google [Bot] and 16 guests