Sticky, test riding the BSG 305 – first of the CNC replacement engines

When Sticky first mentioned he was planning to write a Lambretta kit book a few years ago I questioned if we really needed one. Of course, since then new developments in the two-stroke tuning world have gone into overdrive and there are so many new engines, casings, kits and new products available that it’s hard to keep up.

This book has really been a labour of love for Sticky. He’s spent countless weeks and months on the dyno, built more engines during the course of his research than most of us will do in a lifetime and ridden every single kit that was available for testing. The book was finally finished and the final proofs were signed off at Stuart Lanning’s Lambretta Museum in Weston Super Mare last Wednesday. We managed to catch up with Sticky for a quick question and answer about the book and why every Lambretta owner needs a copy.

If you’re quick you can get one of only 500 hard cover copies autographed by the author. You can also pre-order softcover copies direct from us for delivery as soon as the book arrives back from the printers around the 20th of July…


26 bolt-on kits dyno tested and analysed to help you decide which suits your needs
SLUK: Up until fairly recent times, Lambretta owners had an off-the-shelf choice of either a TS1, or RB kit. Why is it that there are now enough kits to fill a great big book?

Sticky: You’ll have to ask the kit manufacturers about that. Everyone and his mum now makes a Lambretta kit. I tested 13 kits for the 125/150/175 engine and 13 for the largeblock 200 casings. On top of that I rode and reviewed about ten different ‘Exotic’ replacement engines built around sand-cast or CNC-machined casings.

In the time I was finishing the book another four kits have been designed and are forthcoming. It’s a crazy time to own a Lambretta because there’s so much choice on offer.

Forthcoming kits that aren’t even available yet

Why does the average Lambretta owner need a book about kits, surely they just buy what their mate is running, or replace their worn-out TS1/favourite kit?

If you just buy what you had before then potentially you may be missing out on whole new levels of performance and reliability offered by a more modern kit.

The point of this book is not to tell you what the ‘best’ kit is because that’s dependent on what you want to do with it. It’s really about helping people find the ‘best kit’ for their application and budget.

Second opinions from people who have been building and riding Lambrettas since this hairstyle was in fashion!
Is this book aimed at spanner-phobics as well as those more adept with the tools?
Yes, definitely. Apart from the dyno tests each bolt-on Lambretta kit has a User Review from a rider and usually a Second Opinion from someone who has a lot of experience building them.

Even if you don’t do your own spannering you can use the information in the book to decide on the kit or engine that best suits your needs and get a shop to build it for you. There’s no shame in doing that. If you aren’t that technical then you may well end up with a better result that has shop back-up.

These little fellas will help to explain gearing…

Can you give a brief rundown of what people can get from reading this; will it help them with set up and exhaust choices?

It’s been two years work and at 372 pages the Kit Book is thicker than the last Spanners Manual. What I’ve attempted to do is to show you the effect of each kit cylinder, so they were all tested on the same engine casing, using the same ignition and carburettor.

I used two of the most popular exhausts (BGM BigBox and Franspeed Race) as ‘base-lines’. As such, you can see how each kit works with a box exhaust suited to low rpm engines and an expansion chamber that works with higher rpm motors. This was the fairest way I could come up with to see what only the kits were doing.

If the kit manufacturer supplied an exhaust with their kit then I tested that too, but there’s another book worth of material in exhausts alone if you wanted to do every one on the market.

Besides the chapters on each kit there are new tips for engine and chassis building to help those fitting kits.

There’s also a big chapter on selecting gearing for each kit and some new tables for making sprocket selections by Final Drive Ratio or by speed per 1,000 rpm.

There’s tons of information on setting-up and all the new tools and methods that you can use if you want to tackle it.

The Dyno Donkey test rig, built so it was quick and easy to swap cylinders on the dyno

How many dyno runs do you think it took to complete the testing and have the fumes harmed you or the environment more?

It took over 1,000 dyno runs to get to this stage. At least if I was committing suicide with exhaust gas it would have been completed more quickly.

How many times did you rebuild the engines?

Every kit was fitted three times: once to test-fit, measure the port timings and squish. Again to do the cylinder head volume and pressure test and a third time when the cylinders were being swapped on the dyno (and pressure tested again).

That was why I built the ‘dyno donkey’ test rig rather than using a Lambretta chassis. It offered much more access to swap cylinders quickly.

Did you have to use a manual to build the engines?

No, it becomes muscle memory after a while. Some of the kits have different torque settings, particularly when there are 7 or 8 head fasteners, so each had to be done individually. Torque settings for each kit are included; where supplied by the manufacturer.

The importance of leak down testing BEFORE you strip a motor
What are the revelations of this book?

One of the biggest is that it’s now possible to have too much power; at least you can if your riding skill level isn’t great.

I’m pretty sure that there are people out there buying high-end engines for reasons of bravado that they aren’t comfortable riding. Pottering around at low revs on a race-spec engine is like towing a caravan with a Ferrari. It’s not what it’s built for.

The point of this book is to steer people to the engines that will suit them, but that will only happen if they are honest with themselves first.

Give us three top tips when building a Lambretta engine?

#1 is to get matching components; so when you pick a kit you get an exhaust, manifold and a carb that are known to compliment it rather than mixing and matching bits from different sources or that you have lying around.

#2 is to buy the best ignition system that you can afford. I’d say that ignition problems still represent a big proportion of Lambretta breakdowns. Nobody riding motorbikes carries a spare stator plate. Anyone who routinely carries a spare stator or CDI doesn’t honestly have an ignition system that they trust. Thankfully the latest ignitions from Ducati (Casatronic) and Vape (SIP) look like a step-up in terms of quality, but it’s too early to say that they are a solution to the problem.

#3 is to leak-down test. Pressure testing really helps to identify potential causes of unexplained failure long before it happens. The Top Tip this time is to pressure test before stripping an engine because it’s a valuable insight into areas of wear or failure.

Top left: This is important, but do you know why? Top right: Kit building tips, problems to look out for and how to solve them

Does the old-school TS1 still perform well against these modern wannabes?

The TS1 is still a good kit and came in mid-pack. I’m still riding one at the moment, but I’ve changed everything except the cylinder on mine. It has a different head, piston, reedblock inlet manifold and carb and it’s been worked on by several different tuners. This is the problem with a kit that has stood still for 35 years. You can upgrade everything that bolts to a TS1 but it will forever miss out on modern features like 8-point head and 4-point exhaust fixing. These are weaknesses that other subsequent kits have improved upon.

If you had a choice of one engine set up based on your research which would you choose and why?

It’s funny but out of all of the engines that I’ve tried, none of them yet have the features that I most want: pumped 2-stroke oil injection and an exhaust powervalve.

The oil pump is simply for convenience: when people are completely re-engineering engines I don’t think it’s too much to ask for a feature that Innocenti and Piaggio first introduced in the 1960s. Mixing 2-stroke oil at every fill-up is a stone-age ball-ache.

The power-valve is worth having because it means you can have two engines in one. You can have lots of peak power for fun, but also something that is well-behaved and tractable at low revs. Ironically there are two ‘exotic engines’ coming with exhaust power-valves in the future, but nothing was available to test yet.

As fuel becomes more bio than ever how do you think tuned engines will fare over the next few years?

I think it’s another hurdle but not an insurmountable one. People in other countries ride using E10 fuel, or worse. For the moment we don’t have to use it in the UK because Super Plus will stay E5. I’m expecting that, after swapping out some of the ethanol-vulnerable parts (oil-seal and fuel lines), tuners will come up with engine set-ups that work fine on E10. If it means going up a jet size or knocking back your timing a degree or so and losing the odd horsepower then that’s a small price to pay to keep doing what you love.

Top left: Two stroke kits explained from the basics, top right: Jetting via ‘plug chops’ and other methods

What’s the best engine you tested for the book?

All the exotic engines were fun in their own way. I like that they are all aimed at very different markets. The GT300 and the KillerCase both struck me as practical propositions. The new reedvalve versions of the Targa Twin 275 go really well and sound fantastic. Maddest of the lot is the new Liquid-Cooled version of the Casa SSR 265.

Not only is there a chapter on each exotic, but I’ve also taken helmet cam footage of each of them that I plan to release on my Sticky Features YouTube channel when I get the time to edit them together. They’ll serve both as promotion for the book and give a rider’s eye view of what each one is like.

When will the book be on sale and how can people get a copy?

I literally finished proofing at 10:30pm on Wednesday night last week. The book will be available from mid-July but you can pre-order copies direct from the SLUK shop from today.

We are also producing a limited run of hard-back copies that will all be hand-signed. These will only be available direct from ScooterProducts.Com via the link below..

Below you’ll find a gallery of some of the page layouts from the book

The Complete Spanner’s Lambretta Kit Book is a 372 page full-colour book. It follows the same A4 format as Sticky’s other Spanner’s manuals. It’s written in an entertaining way and will appeal to Lambretta owners of all skill levels.

The limited-edition signed hardback can be bought ONLY by clicking this link (whilst stocks last). It costs £29.99.

Pre-order your softback SLUK Shop copies here – PRICE INCLUDES POSTAGE