Rotax 300 builld

Anything related to Lambretta or Vespa Scooters fitted with LC, Motorcycle and/or Auto engines!
ducksta
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start to finish how long to make a cylinder?
live life your a long time dead
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RManson
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An evening and the following afternoon, but that's me fudging through it. I could knock one out in a few hours now.
stokky
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ha ha ha you must have an arm like popeye

when I knock one out, its all over in a few seconds !!!!!!!!!!

ooh er missus !
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RManson
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HAHAHAHAHA!
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RManson
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I added a clamp to the master cylinders as I didn't trust that an o-ring would keep them tight. A modified aluminum line clamp does the trick and ensures the cap won't vibrate loose.

ImageRotax Lamby build-083 by PotvinV8, on Flickr
Last edited by RManson on Wed Aug 30, 2017 10:49 pm, edited 1 time in total.
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RManson
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Using the foam mock-up tank, I was able to make the real deal using stainless sheet. Here are the pieces prior to assembly...

ImageRotax Lamby build-090 by PotvinV8, on Flickr

And the finished product...

ImageRotax Lamby build-091 by PotvinV8, on Flickr

I knocked out some 5/16-inch stainless bungs that will serve to mount the tank. The recessed end will be welded to the frame while a tapped bung will be welded to the tank. Rubber snubbers in between help isolate vibration.

ImageRotax Lamby build-092 by PotvinV8, on Flickr

Here's a terribly blurry shot of the tank prior to installation. That big fitting is a roll-over valve for venting while the smaller valve is a return, required by the Mikuni Super BN carb. You can't see the outlets (full and reserve), but they're on the bottom of the tank at different heights. These will run separately to the aforementioned valve so that a reserve function is still possible. You can also see the threaded bungs tack welded to the top of the tank. After finish welding, I'm going to add a welded strap that will straddle the tank across the bung's location to provide more "meat" for the mounts, hopefully preventing the bungs from tearing away from the tank.

ImageRotax Lamby build-093 by PotvinV8, on Flickr

And the whole ball o' wax installed...

ImageRotax Lamby build-094 by PotvinV8, on Flickr
Last edited by RManson on Wed Aug 30, 2017 10:54 pm, edited 1 time in total.
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RManson
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I'm using a pop-up cap for the filler, accessed under the seat.

ImageRotax Lamby build-095 by PotvinV8, on Flickr

A quarter-turn of the center cap causes it to spring up...

ImageRotax Lamby build-096 by PotvinV8, on Flickr

Where it can then be unscrewed from the bung.

ImageRotax Lamby build-097 by PotvinV8, on Flickr
Last edited by RManson on Wed Aug 30, 2017 10:55 pm, edited 1 time in total.
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RManson
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I wanted to retain as much of the original Lambretta character as possible and that meant to me that the radiator needed to be downplayed somehow. In the back of my mind, this meant wrapping the whole business in some type of shroud. Enter one clapped out Rally 200 glovebox. It obviously needs to be modified to cover the radiator and fan, but it looks like it will work.

ImageRotax Lamby build-098 by PotvinV8, on Flickr

The first step was to tack weld two Dzus tabs to the legshields to provide support to the top panel. At this point, we can see how much material needs to be added to the glovebox in order to cover the radiator.

ImageRotax Lamby build-099 by PotvinV8, on Flickr

To make the patch panel, first I made a template using construction paper.

ImageRotax Lamby build-100 by PotvinV8, on Flickr

Once I was pleased with the fit of the template, I translated the Dzus button locations.

ImageRotax Lamby build-101 by PotvinV8, on Flickr

I then transposed the template onto a sheet of 20-gauge mild steel and cut it to shape, drilling and recessing the holes for the Dzus button mounts last.

ImageRotax Lamby build-102 by PotvinV8, on Flickr

With the top panel in place, I then marked and trimmed the glovebox and tack welded the two together.

ImageRotax Lamby build-103 by PotvinV8, on Flickr

I used the same process for the bottom panel, which isn't visible from this angle, before mounting a pair of Dzus fasteners to the lower side corners as well. A pair of similar panels for the sides will finish up the glovebox/shroud.

ImageRotax Lamby build-104 by PotvinV8, on Flickr

About the only complaint I have so far is that it's mounted a bit low because I'm using the front fender area to pull air through to feed the radiator. Give and take I guess...

ImageRotax Lamby build-105 by PotvinV8, on Flickr

Once everything is tacked together, I'll weld it all up and perhaps add some louvers to help evacuate the air. If not, I figure I can make a set of arms that allow the glovebox door to remain open whilst riding and close up for show. Either way, it ain't gonna cool very good without some way to get the hot air out!
Last edited by RManson on Wed Aug 30, 2017 10:57 pm, edited 1 time in total.
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DigDug
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You should put this thread in a book.

If you do I'd like to reserve my copy now!


8-)
Did you have to do that?
shamrockexpress
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Youre a handy bugger!!!!!!!!!! :D

keep er lit ya boy ya!!!!!!!!!!!
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