Rotax 300 builld

[RManson]

Grille opening comes in at 15 sq. inches while the radiator is around 80 sq. in. That's roughly 1/5 the core, so using Warts' theory above, it should be okay. Plus, it will be easier to fabricate a grille to cover two fairly flat openings as opposed to one big one that needs to be bent around the frame tube. If it turns out to be too small, it's easy to hog it out later.

On another note, got the Aprilia clocks mounted with a custom white carbonfiber panel. Kinda hard to see the carbonfiber but you get the idea. Might change out the tach for something a bit more interesting, but will depend on how easy it is to pick up a tach signal due to the Aprilia ignition.

Rotax Lamby build-024 by PotvinV8, on Flickr

Was also playing around with the headset and it looks like it needs to sit lower than it currently is. That will require some mods made to the bottom of the headset as the bracket that mates it to the fork won't bolt on as-is.

Rotax Lamby build-025 by PotvinV8, on Flickr

Unfortunately, the brake master hits the legshield as it sits now so any lower and it's going to be an even bigger problem. I'm wondering if a radial master might solve this problem or if I'm stuck trimming the corners of the legshield? Going to have a clutch master as well so it's a bit of a problem at the moment, but nothing a cut off wheel can't solve!

Rotax Lamby build-026 by PotvinV8, on Flickr

Rotax Lamby build-028 by PotvinV8, on Flickr

Anyhow, thought I'd post a bit of progress, however minor it may be. More to come...

[Dryballs]

I tried that master cylinder on my LTH brake a few years ago... It was crap. Far too wooden feeling.

Basically its too big for scooter brakes. I fitted it on my Moto Guzzi with 2 big calipers and it was mint.

Nice build by the way!

Cheers,

db

[RManson]

Thanks DB. What size master were you using?

[Dryballs]

Not sure... I think it was about 17mm

[warts]

There are loads of guzzi master cylinders. Mine are 13mm, but go up to at least 16mm, maybe bigger, early or later, big or small block, linked or not.
Re the radiator, ducting round the outside will ensure the air goes thru the core rather than spill round the outside. A small return edge or lip round the hole will also increase flow efficiency.
Anyway, nice build.

[Dryballs]

Mine wasn't a Guzzi mc... It was a nissin one the same as the pic.

I just put it on my Guzzi when it didn't work on the lammy

[RManson]

Machined the headset a bit so that the fit was better. Nice and tight with the leggies now without the headset bracket in the wrong position...

Rotax Lamby build-029 by PotvinV8, on Flickr

Also machined a bezel and hold down clamp for the billet LED kill button. This is triggered via a key fob like a new car. System comes on when the fob is within a certain proximity, push button and ignition is on, then start kickin'. This replaces a traditional key and allows one to leave the fob in a pocket; just walk up and go. Used these in custom car applications before, a bit overkill for a scooter, but I had a kit and thought it'd be nice.

On:

Rotax Lamby build-030 by PotvinV8, on Flickr

Off:

Rotax Lamby build-031 by PotvinV8, on Flickr

[RManson]

Was up to the usual metalwork, filling holes and fixing cracks in the sheetmetal when I came to the hole in the legshield for the radiator. Figured I'd take ya'lls advice and heed the old 'better safe than sorry' adage and decided to cut a nice big hole to cool the beast.

Covers the entire surface area of the radiator now all within the confines of the front mudguard so it'd better cool...

Rotax Lamby build-032 by PotvinV8, on Flickr

[RManson]

Also filled the stock toolbox, fuel filler, ignition switch hole and other various undesirables. Welding on the rather thin Lambretta sheetmetal left a bit to be desired when it came to finish metalworking all the welded bits. I guess that's why they invented body filler!

Next stop, the sandblaster!

Rotax Lamby build-033 by PotvinV8, on Flickr

Rotax Lamby build-034 by PotvinV8, on Flickr

Rotax Lamby build-035 by PotvinV8, on Flickr

[mick1]

very impressive. more so because you've documented the whole project, masses of photo's. I think there could be a book at the end of it