Series 2s, bench seats and air scoops...

[señorblanco]

Hello! I bought my first Lambretta in October. It's an Li series 2 and she came with two saddle seats. I'd like a bench seat but understand this will obstruct the air scoop? Can somebody tell me if this affects the performance to the point of making it something to avoid? Does anyone manufacture a bench seat that simultaneously utilities the scoop? How has it affected your scooter? Cheers.

[Warkton Tornado No.1]

As standard, the TV175 in SII form was fitted with a bench seat, as were the majority of SIII, so air flow was taken into account with the design of the underside. Even many, if not all, aftermarket seats will have that feature built in.

[MK Monty]

Most bench seats are open at the front, not the very low snettertons and the like. I would go for a GP type scoop as it's bigger and fully upen at the front so no air restriction till it's at least at the air box. It's one of those you can't see it, it may help, so why nots. unless you want to stay standard, if so keep the saddles

[ToBoldlyGo]

Hah! That's ironic, people complaining about bench seats restricting airflow on a S2 with possibly the most restrictive air scoop, box set up of the lot. You'll be fine with a bench seat providing you carry out a few simple tasks to improve the air flow. Things like removing the baffle in the scoop for a start. The air box is a bit more tricky, because the neck will be restrictive. You'd either have to fit an airbox from a 175 or use a S3 airbox. But then that would mean you'd need a S3 toolbox as well. Alternately you could drill holes in it.

[Warkton Tornado No.1]

Post by ToBoldlyGo » Tue Dec 13, 2016 2:58 pm

Hah! That's ironic, people complaining about bench seats restricting airflow on a S2 with possibly the most restrictive air scoop, box set up of the lot. You'll be fine with a bench seat providing you carry out a few simple tasks to improve the air flow. Things like removing the baffle in the scoop for a start. The air box is a bit more tricky, because the neck will be restrictive. You'd either have to fit an airbox from a 175 or use a S3 airbox. But then that would mean you'd need a S3 toolbox as well. Alternately you could drill holes in it.

Does this now apply to all SII's or just those that have been modified & need more air? I apologise for my ignorance if so , but I presume that a standard SII air induction side will cope adequately with the standard carburettor/barrel/exhaust set up.

I guess any modifications as you suggest can do no harm, but I was thinking that any changes should be kept to a minimum if the bike runs well & all he's seeking is advice on a seat.

[HxPaul]

Hah! That's ironic, people complaining about bench seats restricting airflow on a S2 with possibly the most restrictive air scoop, box set up of the lot. You'll be fine with a bench seat providing you carry out a few simple tasks to improve the air flow. Things like removing the baffle in the scoop for a start. The air box is a bit more tricky, because the neck will be restrictive. You'd either have to fit an airbox from a 175 or use a S3 airbox. But then that would mean you'd need a S3 toolbox as well. Alternately you could drill holes in it.

I have a 1960 series 2 and I use a series 3 airbox.I haven't found it necessary to change the toolbox,although the top fastener is very close to the airbox.

[ToBoldlyGo]

Post by ToBoldlyGo » Tue Dec 13, 2016 2:58 pm

Hah! That's ironic, people complaining about bench seats restricting airflow on a S2 with possibly the most restrictive air scoop, box set up of the lot. You'll be fine with a bench seat providing you carry out a few simple tasks to improve the air flow. Things like removing the baffle in the scoop for a start. The air box is a bit more tricky, because the neck will be restrictive. You'd either have to fit an airbox from a 175 or use a S3 airbox. But then that would mean you'd need a S3 toolbox as well. Alternately you could drill holes in it.

Does this now apply to all SII's or just those that have been modified & need more air? I apologise for my ignorance if so , but I presume that a standard SII air induction side will cope adequately with the standard carburettor/barrel/exhaust set up.

I guess any modifications as you suggest can do no harm, but I was thinking that any changes should be kept to a minimum if the bike runs well & all he's seeking is advice on a seat.

Nothing is compulsory White Tornado. I got a bit carried away, that's all. If it goes and he's happy with it don't knock it. But, if he's getting into it I should imagine that he might want a little more than that before long.

[Warkton Tornado No.1]

Post by ToBoldlyGo » Tue Dec 13, 2016 7:41 pm

Warkton Tornado No.1 wrote:
Post by ToBoldlyGo » Tue Dec 13, 2016 2:58 pm

Hah! That's ironic, people complaining about bench seats restricting airflow on a S2 with possibly the most restrictive air scoop, box set up of the lot. You'll be fine with a bench seat providing you carry out a few simple tasks to improve the air flow. Things like removing the baffle in the scoop for a start. The air box is a bit more tricky, because the neck will be restrictive. You'd either have to fit an airbox from a 175 or use a S3 airbox. But then that would mean you'd need a S3 toolbox as well. Alternately you could drill holes in it.


Does this now apply to all SII's or just those that have been modified & need more air? I apologise for my ignorance if so , but I presume that a standard SII air induction side will cope adequately with the standard carburettor/barrel/exhaust set up.

I guess any modifications as you suggest can do no harm, but I was thinking that any changes should be kept to a minimum if the bike runs well & all he's seeking is advice on a seat.


Nothing is compulsory White Tornado. I got a bit carried away, that's all. If it goes and he's happy with it don't knock it. But, if he's getting into it I should imagine that he might want a little more than that before long.

None taken, ToBlobbilyGlow

[señorblanco]

Thanks for the replies, fellas.

I suppose buying one and trying it will be the best way to find out. All advice duly noted. I plan to modify sparingly and only then make changes that can be undone.

[ToBoldlyGo]

That's probably wise. Bottom line is, as has already been pointed out, you don't have to do anything to it to get it to run as intended providing it is clean and running. You can always change things if you feel the need for speed.

[señorblanco]

Hi, chaps! Thought I'd tag this on the end rather than start a new thread.

Today I fitted a bench seat. To begin with, it wouldn't 'lock' properly when pushed into the catch plate. I found that if I removed the two rubber buffer things on the underside of the seat it'd lock perfectly in place but then wouldn't bloody open! I had to unscrew the back and try again but not before pulling various muscles trying to open it.

Any solutions? Right now it clicks down into place and re-opens but isn't 'locked' there needing you to push the seat in to free it. Thanks!

[ToBoldlyGo]

Don't dispense with the two rubbers. You don't really want the seat frame resting directly on the catch plate. It's possible to bend the tongue in some cases so that it locks more smoothly. Or, you may need to elongate the hole in which the catch locks slightly. You do have rubbers mounted beneath the catch plate I take it? If you're having to drop the seat to get it to take the actual catch plate might be too low. Hence my question about the rubbers.

[señorblanco]

Don't dispense with the two rubbers. You don't really want the seat frame resting directly on the catch plate. It's possible to bend the tongue in some cases so that it locks more smoothly. Or, you may need to elongate the hole in which the catch locks slightly. You do have rubbers mounted beneath the catch plate I take it? If you're having to drop the seat to get it to take the actual catch plate might be too low. Hence my question about the rubbers.

Rubbers mounted beneath the catch plate you say...

I do not. Can you please link me to what I need to buy?

[HxPaul]

Don't dispense with the two rubbers. You don't really want the seat frame resting directly on the catch plate. It's possible to bend the tongue in some cases so that it locks more smoothly. Or, you may need to elongate the hole in which the catch locks slightly. You do have rubbers mounted beneath the catch plate I take it? If you're having to drop the seat to get it to take the actual catch plate might be too low. Hence my question about the rubbers.

They usually have either nylon washers or metal washers under them.http://www.lambretta.co.uk/shop/seat-sp ... -1495.html

[ToBoldlyGo]

These are the official parts...

http://www.scootopia.co.uk/product/7239 ... -14mm-head

I can't recall which way around they go offhand. You either use the white nylon ones on the back and plain ones on the front, or t'other way around. But to be honest I find tap washers very good. I just open out the middle a bit. And of course you can get them at your local hardware store. I'd probably just put tap washers under the seat catch if it was me. As it sound like that might be where your problem is.

[señorblanco]

Thanks very much for the info/links, I'll get on it - appreciated!