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My aim was to do a reed crank induction on my Lambretta. Thinking it was a waste using a Lambretta barrel (the carb' inlet needing to be blocked off) i decided to use a Vespa 221 MHR, which was cheaper than most Lambretta kits

I had a spare Spanish 150 casing out of a 76' Li and a solid series 2 Spanish frame for the new engine to go in. I also had some MK 2 Vijay forks that i wanted to use. This was my basis for the build but there was plenty of bits still to buy.

I started this just before Christmas 2018 when i approached a local engineer with regards to the welding and machining required. He said he needed the crank and a reed block would be easier than making our own, these were duly purchased (107x60 crank) from AF and an MB shorty.

With my brand new MHR kit, reed block, crank and casing i met with the engineer. It was decided to skim the face of the casing then weld a new aluminium "ring" on the end. This was to be 20mm+. The reed block was more of a challenge. We discussed the size of the opening we were going to create and clearance issues with the frame and other engine parts (cable adjuster block for one).

In the new year we had it something like:

IMG_20181228_102240 by mick leaf, on Flickr

IMG_20190109_152549 by mick leaf, on Flickr

IMG_20190107_134622 by mick leaf, on Flickr

IMG_20181228_102230 by mick leaf, on Flickr

IMG_20190119_112139 by mick leaf, on Flickr

IMG_20190109_152604 by mick leaf, on Flickr

IMG_20190109_152609 by mick leaf, on Flickr

Will continue later....trying to show photos rather than links........any ideas ?

Good luck with it

Very interesting. I like a photo-story.

I did a reed into the crank case many years ago (CR500, so a BIG reed) which sat where the web between the engine lugs is. The block faced forward and fed into a void between the barrel and the crank, so the route was not obstructed by the crank webs. The position of the carb was dictated by the manifold between the carb and the reed.

I did modify the frame for lots of other good reasons, including a horizontally mounted the rear shock, and I guess your solution means you don’t have to cut the frame behind the engine mount, like I chose to. Frankly, I don’t blame you, as mine ended up being very complicated.

Anyway, keep the story coming. This is one I will be watching with interest.

i'm assuming when you click on the photo link you can enter the gallery and see the rest of the photos ?

I have viewed other photos Mick. There were thumbnails at the bottom of the page, and I clicked on them to see other images.

I looks like the lens could have done with a wipe though

[quote="MickYork"]Will continue later....trying to show photos rather than links........any ideas ?[/quotes]

Try this......

Hmmm. That ^ isn’t showing any images on my iPad. Can anyone see any images on their phones or PC’s?

Perhaps you can’t show images from Flickr accounts???

Nice bit of welding but isn’t one of your cylinder studs on the piss?

Scooterdude wrote:Nice bit of welding but isn’t one of your cylinder studs on the piss?

No......well not enough to matter... cylinder fits ok. Photo not the best, which may be a factor.

Managed to put the top end together without any dramas but had a problem with the gearbox

I'd purchased the cheapest gearbox i could find (GP) but when tightening the end plate the box kept on seizing. After trying different shims and spacers i noticed a slight casting burr on the casing under the xmas tree. 30 seconds with the dremel and the box turned smoothly. Trying to solve the tightening issue i'd fitted the Spanish G/box back in.......and decided to leave it. I've also got an AF cassette clutch, GT chain tensioner and a modified side Li side casing to work the GP style clutch. The carb' i'm initially using is the cheapest i could find....a pwk copy, 34mm with powerjet.....£18 ........by the way, i'm from Yorkshire

nice work mick, ive completed the same job with a rotax barrel, its nice to see some variation and thinking outside the box, keep the pictures coming, I like this kind of thread as well, if you go on flicker and bring up the picture you want to post, click on the share curved arrow at the bottom, then copy, that's right click if you don't know, then paste it to your post and the photo will be on the post, rather than a link. I used the reed inlet off an rb20 barrel on mine. Untitled by stephen holt, on Flickr

Cheers Holty

raptor engine build by mick leaf, on Flickr

Mine originally came out at 90* like yours, changes to the design now means it points towards the rear shocker.

Ok, so all going to plan.....but as we say "if it's all going to plan you've got the wrong plans"

Sure enough i offered the engine into the series 2 frame....(i'd cut the loop away with plans for a removable back section), but......
series 2 frame by mick leaf, on Flickr

It appears the head on Vespa is quite a bit taller than a Lambretta. The head is too close to the frame and the spark plug is not offset and would be impossible to get at.

The options i considered were: Remove fins and cut new hole for plug.
Fit a Lambretta head (probably Avanti)
Alter frame
What i decided to do was:

Ld frame 1958 French by mick leaf, on Flickr

Cut up a 1958 French Ld and put the engine in after removing "surplus" structural frame work. To be fair i'd had the frame for over 10 years with the intention of fitting a Li/GP engine but had never got round to it. Anyway, got the angle grinder out and went to work. I had a rear section of a series 2 frame to hold the engine, so the intention was to graft this into the Ld.

Here was the first attempt at fitting the engine (i don't have a garage and most of the work is done "al fresco"):

QMT Raptor by mick leaf, on Flickr

I'll explain about the next change of plan (x2) in my next post

The position of the seat in first attempt was un-rideable, it was too high. I was concerned about the ground clearance for the exhaust and angled the engine to suit.

Here's my second attempt alongside the 1st attempt:

QMT Raptor by mick leaf,

Raptor by mick leaf, on Flickr

This was looking better, although the exhaust ground clearance was worrying. Finally settled on attempt number three:

IMG_20190414_094449 by mick leaf, on Flickr

Initially it's bolted together with a few tack welds, when i'm happy with it i'll strip it down and do some serious structural welding.

What length is the wheelbase gonna be ?

Approx' 55", roughly 5"longer than a "standard" Lambretta

I've seen a few modified Ld's with the cylinder pushing through where the bridge piece is, thought idytry something different and the longer wheelbase appealed to me........as for how it will handle

MickYork wrote:Approx' 55", roughly 5"longer than a "standard" Lambretta

I've seen a few modified Ld's with the cylinder pushing through where the bridge piece is, thought idytry something different and the longer wheelbase appealed to me........as for how it will handle

Yep, that will be interesting in the corners

Couple of side issues and slight change of plans:

As i'd originally planned on putting the engine in a series 2 with the GP forks, i had to extended the forks to fit. This was done. When i changed the frame to the Ld i discovered the fork stem on an Ld was longer than a series 2, which meant.....lengthening the forks for a second time. Job done and and fits well.

I'd also originally planned on using a customised headset:
IMG_20190526_111526 by mick leaf, on Flickr
IMG_20190526_111547 by mick leaf, on Flickr
I'd bought this of ebay a few years ago and presumed it was Series 3 gp modified headset. It was bought with no internals and no description.

It fitted reasonably well but caught on the top of the horncasting. I trimmed the horncasting suit and it looked ok.
IMG_20190419_140305 by mick leaf, on Flickr

I then decided to buy the internals....duly bought...but didn't fit

I took the headset up to AF and showed it to Ben and Scot...there was a mixed opinion, the internals were a series 2 but the headset clamp was definitely a series 3 ? It was suggested it could be off a 3 wheeler or it was some sort of hybrid ? either way series 2 internals were needed. I'd also intended fitting a GPS speedo and that would need the headset modifying.

I decided to put this headset to one side and use the original Ld handle bars. This required a new gear change and a Hydraulic brake/throttle. The brake and throttle was simple enough as these are standard motorcycle parts. For the gear change i bought an MB set up.

IMG_20190526_111347 by mick leaf, on Flickr

quite pleased with the result....but....it turns out that the Ld forks are a slightly larger diameter than the GP ones This meant making a thin bush to fit inside the clamp. Another annoying hic-up but got it sorted and fitted.

It seems every little problem has a knock on effect and creates more issues.....still onwards and upwards.

Quite some project! Nice creative thinking 'outside the box'. Nice welding and workmanship too.

Well done.

Indeed, I admire ur perseverance on this build well done

Nice. Glad you went with the mk1 bars. My first scooter was a mk1 ld125 and I've had a soft spot for that look ever since.